Please enjoy this transcript of my interview with Dr. Tommy Wood (@DrRagnar), an associate professor of pediatrics and neuroscience at the University of Washington, where his research focuses on brain health across the lifespan. Alongside his academic work, Tommy is head scientist for Motorsport at Hintsa Performance, overseeing health and performance programs for multiple Formula 1 drivers. He also helped to found the British Society of Lifestyle Medicine, is head of research for the dementia prevention charity Food for the Brain, and serves as chief science officer for brain-health coaching company BetterBrain. He is co-host of the Better Brain Fitness podcast and author of the forthcoming book The Stimulated Mind.
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Dr. Tommy Wood — How to Future-Proof Your Brain from Dementia
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Tim Ferriss: Tommy, Tommy, Tommy, nice to see you.
Tommy Wood: Nice to see you.
Tim Ferriss: Thanks for making the time.
Tommy Wood: Yeah. Thanks for having me.
Tim Ferriss: Absolutely. And as mentioned before we started recording, this is just going to be like our last conversation, because I wanted to reach out to you because cognition, cognition, cognition. Boy, oh, boy, is that on the mind. And pun intended on one level, but we are going to bounce all over the place, and I hope to give people, including myself, a lot of tactical, practical recommendations. Also being clear where the science is solid and where the science is maybe a little thinner ice.
Tommy Wood: Mm-hmm.
Tim Ferriss: Right?
Tommy Wood: Yeah.
Tim Ferriss: Or where something is plausible but not yet proven out. And you’ve got me chewing xylitol gum, you’ve got me looking at air purifiers, but I’m skipping ahead. Let’s go back to the beginning, and I want to give the good old Dr. Chatterjee a nod here because it came up in a conversation you had with him and I was like, “Wow, I never would have thought of that.” Why are human babies so plump? Why are they so fat compared to other species?
Tommy Wood: If you look at human babies compared to pretty much every other mammalian species, we are the only species that’s born fat, even compared to other primates. And it’s thought that the primary reason for this is that that fat is a repository for things that the brain needs in order to develop. And the two that are probably most interesting to you and seem to be particularly important are DHA, the omega-3 fatty acid, and fats as a source of ketones for the brain. When the brain is developing in particular, and I think this is also very relevant to recovery from brain injuries and other states, the preferred synthetic precursor, as in the thing that the brain uses to make structure like fats and cholesterol and that kind of stuff, which makes up a significant chunk of the brain. Ketones are the preferred source, particularly in the developing brain, but I think also later on in various states as an adult.
And so in order to support that very hungry brain, which it is particularly in humans, we’re born fat so that we can generate a bunch of ketones to support that brain developing for the first — you know? Especially for the first few weeks, but maybe even for months after that.
Tim Ferriss: Also, lots of, as I understand it, beautiful bat brown adipose tissue, to keep those little hairless —
Tommy Wood: Keep them warm. Yeah.
Tim Ferriss: — monkeys warm. Yeah. All right. So we’re going to talk about, because I think the, in a sense, the extremes inform the mean, but not the other way around. So we can talk about certain maybe edge cases, things that people might not view as immediately relevant to themselves.
But since we’re talking about newborns, I’m curious, you’ve looked at therapies, various types of research into brain injury and newborns. What do you do? What can you do? I mean, what’s the state of the art when it comes to treating brain injury in newborns or in infants?
Tommy Wood: There’s two main brain injuries of babies that I study, and they’re probably also the two main brain injuries that are most broadly studied, just because of their impact. And so the first is preterm brain injury. So that’s a baby’s born early, the earlier you’re born, the greater the risk of neurodevelopment of impairment or some other kind of neurological disorder, cerebral palsy, other impairments later in life. And the other is something that we call hypoxic ischemic encephalopathy, which is essentially you get to normal full term, something happens —
Tim Ferriss: Not enough oxygen? Exactly.
Tommy Wood: Exactly. Not enough blood flow, not enough oxygen gets to the brain. Something happens, usually during childbirth, and people think about the cord is wrapped around the neck or you can get placental abruption, right? The placenta kind of tears off the inside of the uterus or the uterus can completely rupture. But sometimes we don’t know what happened, the baby just comes out and something has happened. In that scenario, the second one, HIE, as we call it, those babies are cooled down. So this is something that I studied a lot in my PhD. You take that baby, and as long as you start within a few hours of birth, you cool them down to 33.5 degrees Celsius for 72 hours. And that significantly reduces death and disability.
Tim Ferriss: That’s 92.3 degrees Fahrenheit for yankees out there.
Tommy Wood: Although even in the US, many of the cooling machines are made in Europe, so they still run on Celsius. So those babies get cooled down, and that’s really the state of the art. Although now we’re starting to figure out that there are still a whole bunch of injuries where that doesn’t help, including preterm babies. So if you’re born preterm, cooling doesn’t help, actually it can be detrimental. And in that scenario, one of the things that they found recently, which is probably most beneficial, is caffeine.
Tim Ferriss: Really?
Tommy Wood: Yeah. Caffeine is not given for neuroprotection. It’s given because babies who are born preterm don’t breathe as well. They have this thing called apnea prematurity. So they don’t have a normal respiratory drive. So you give caffeine to stimulate that, but the trials that used caffeine to treat apnea prematurity, saw significant improvements in cognitive function.
Tim Ferriss: And those were durable improvements, or just during treatment with caffeine?
Tommy Wood: Yeah. So when you do these kinds of trials, usually you follow those babies up to something like two or three years old. That’s mainly because an NIH funded trial or an NIH grant lasts five years. So if you’re going to do a full trial in five years, then you can only follow — You have a year or two to enroll and treat, and then you have two or three years to follow them up. And so they see significant improvement at that age, but then also going into childhood, which is ideal. You really want to look out as far as you can. So then there’s now a renewed interest in caffeine and other brain injuries in babies, and that’s something that we’ve tested in my lab. There are some trials now starting in other brain injuries. But beyond that, in both groups, really the biggest impact on later outcomes is the home environment that kid goes back to.
So yes, my colleagues who are practicing neonatologists do a whole bunch of amazing stuff to keep these babies alive and keep their brains in good shape as much as they can when they’re in the intensive care unit, but actually the home environment is where the biggest impact happens, and so then that means that even if you have an imperfect start to life, there’s probably a lot that you can do as a parent, to help that brain to develop and grow as normally as possible.
Tim Ferriss: All right, we’re going to continue to talk about brain injury for a little bit, and then we’re going to talk about a whole lot of multifactorial prisms around cognition and whether or not you can intervene with the fates to preserve or enhance cognition as an adult. So we’re going to get to that. But if we make the hop from infant to adult, right, if you slipped on the ice and hit the back of your head and suffered a severe concussion, what would you personally do after that?
Tommy Wood: There are a few things that I think we can probably do, and we actually wrote a paper about this, came out last year, that covered various nutritional strategies, and most of the strategies would be nutritional supplements that I would probably lean on. And assuming that I didn’t have any control over what happened beforehand, ideally I do lots of things to improve the health of myself, because I think that’s going to affect how my brain and body then respond to the injury. But after that point, then there’s a couple of things that I would do. One, is I would manage fevers. So this goes back to the hypothermia that we talked about in babies. Lots of trials have tried hypothermia for traumatic brain injury in older humans and adults, and they haven’t really shown any benefit. What does seem to be beneficial is preventing hyperthermia.
So if you have significant trauma, one of the things that happens as the immune system gets activated is you get a fever. And that fever increases this gap between the metabolic demand in the brain and the supply of energy, because the mitochondria become damaged during the injury. So if you increase that gap because the higher metabolic rate, because you’re hotter, that seems to make that injury worse. And this has been found in some animal models, but also in some human data. So the most important thing to do is to prevent fevers.
Tim Ferriss: So, get your flu shots, et cetera, other things?
Tommy Wood: Well, so in this scenario, if you need to take Tylenol to prevent a fever —
Tim Ferriss: I see, take acetaminophen.
Tommy Wood: Right. Yeah, yeah.
Tim Ferriss: Right.
Tommy Wood: Yeah, acetaminophen, paracetamol, depending on where you are in the world.
Tim Ferriss: Yeah, where you are. Yeah.
Tommy Wood: Maybe even there are some devices where you can do some neck cooling or head cooling. They probably don’t have as much of an effect as some people think they do, but whatever you can do to maintain your body temperature. And so, antipyretics, so things that help prevent fevers, are going to be helpful. I would then also manage blood sugar. The main thing being probably avoiding things that are going to cause large glucose spikes. So avoiding refined carbohydrates, and —
Tim Ferriss: Why does that matter acutely after you whack your head?
Tommy Wood: So you see, again, in multiple studies, and we have to do this experimentally. So some of this comes from animal models, but if you create diabetes or the hyperglycemic during the injury or immediately afterwards, and some of it is driven by the injury, if you have an acute injury, you’re going to get higher blood sugar. So some is cause, some is effect, but it seems that these high glucose spikes are, again, stressful in that setting of an acute brain injury. So just minimizing that as much as possible. That doesn’t mean that you shouldn’t eat carbohydrates, but just I would avoid refining carbohydrates. When I worked with athletes at high risk of concussions, if you’re being taken off the field, a low risk thing is just to not chug Powerade as you’re being taken down the tunnel.
Other things that are going to become important with varying degrees of evidence, but still good enough that there’s a high positive asymmetry, right, high possibility of benefit with low risk, creatine supplementation. Creatine is probably more beneficial if you have it on board beforehand, but there’s at least one trial in pediatric TBI that showed creatine enhanced recovery. Omega-3 fatty acids are the same, would certainly include those as well. And then the next thing I would do is I would take exogenous ketones. I have them at home, there are things I’ve played with. I don’t use them regularly, but in this setting, again, I think there’s enough promise to suggest that they’re worth taking. I didn’t include that in this paper because we don’t have good evidence for it, but if I had a brain injury, I would take exogenous ketones.
Tim Ferriss: I would too.
Tommy Wood: Yeah.
Tim Ferriss: I would too.
Tommy Wood: And then there were a few other things that have an increasing amount of evidence for them. So there’s some studies on some B vitamins, particularly riboflavin, branch chain amino acids seem to be beneficial, and that seems to be by improving sleep. Then if you have sleep issues, melatonin has some evidence for it as well. I would avoid caffeine actually in this scenario. There’s a little bit of evidence that says that again, it’s probably due to increasing brain metabolic rate in that sort of early window, similar to high temperature. So I would avoid caffeine particularly early on. And then probably the most important thing that we have evidence for, is early return to physical activity. So low level aerobic exercise, as soon as you can tolerate it at a level that doesn’t make symptoms worse, and then increasing that over time as you get better, that’s going to be an important part of recovery as well.
Tim Ferriss: What’s the supposed mechanism of action with the return to physical exercise and the impact that has on the recovery from, say a concussion?
Tommy Wood: Yeah, there’s probably a few different mechanisms, and to be honest, I don’t think anybody really knows. Again, the evidence is best in pediatric brain injury, particularly pediatric sports related concussions, that’s where they’ve done most of these like randomized controlled trials. But there’s a few things that are going to be happening. You’re going to be improving cerebral blood flow, probably going to get a whole bunch of myokines, exokines that get released during physical activity. We know many of those can have a beneficial effect on the brain. And then you may also see improvements in sleep, right? We know that physical activity helps support sleep. So many of those could be going on at the same time, as long as you’re not doing a level of activity that’s then making symptoms worse.
Tim Ferriss: Mm-hmm, right. So we’re going to take a moment, not for a commercial break, but just for a topical break, to ask a very important question, which is, when you came in second at Washington’s Strongest Man in 2024, and then when you came in the top 20 in the world’s first ever fully off-road Ironman triathlon, what were your weights? What was your body weight in both of those cases?
Tommy Wood: So those two competitions were more than a decade apart, I will say. So in 2012 was when I did the world’s first fully off-road Ironman. It was initially called X-Man, and then Marvel sued the company. So it ended up being called X Tri ’24.
And so when I did that, I think I was probably something like low, 80 kilo, 82, 83 kilos, so like 185 pounds, something like that. And then fast-forward a decade, when I was competing in Washington’s Strongest Man, I was in the middleweight class, and to get into that class, I had to basically diet down and then do a water cut to get under 198 pounds. So I was just under 90 kilos on the day, although normally I’d hang out like 15 pounds higher than that.
Tim Ferriss: Yeah. Okay, super interesting. We may come back to that. Certainly going to talk about your own personal routines and tricks of the trade that you apply. Before we do that, I want to tie up a couple of loose ends, specifically infant baby, this thing you mentioned, DHA, and why that, and/or omega-3s more broadly speaking are important, right? And I, for instance, I’d say one meal a day is probably right now two cans of sardines, or chub mackerel mixed with some type of oil, like olive oil or MCT oil, with a splash of apple cider vinegar. It’s shockingly good, it sounds like cat food. It’s actually better than it sounds, with some salt. But could you explain why this DHA, et cetera, is important? You also mentioned the omega-3 in the context of recovery from brain injury. So why is it important and what is the prescription, so to speak? How can people translate that into something they actually do?
Tommy Wood: When you think about, again, sort of the structure of the brain, and you’re trying to develop the brain in the first place, then —
Tim Ferriss: Big pile of fat.
Tommy Wood: Big pile of fat. And a lot of that fat is DHA. And actually brain, if you don’t mind eating brain, brain is a great source of omega-3s.
Tim Ferriss: I tried it, I tried cheap brain in Turkey. I’m going to tell you, the presentation could have used some work. It was just like straight out of the formaldehyde jar plopped onto a plate. It was a bit much for me, to be honest, but, yeah.
Tommy Wood: You can fancy it up if you want, but equally, brain consumption is not required. So DHA tends to concentrate at the synapses of neurons. It seems to be really important for helping to regulate the release of neurotransmitters, like being part of the structural component of those synapses. It also tends to accumulate in mitochondria, and the DHA content of mitochondria is positively correlated with their capacity for energy production. Some of it could be due to some weird physical, as in physics properties of DHA, like how electrons move through it differently from other fats.
But anyway, it seems that particularly for mitochondrial function as well as synapsic function, DHA is critical, and so it sort of preferentially accumulates in those areas. Very important during brain development, so much so that the mother will sacrifice her own DHA stores so that the baby gets enough if she’s sort of borderline in terms of DHA levels. And it’s also why women in general tend to be better at converting shorter chain omega-3 fatty acids like ALA to DHA and EPA. It’s thought that that’s because that’s going to be needed for a baby one day, more so than in men.
Tim Ferriss: So eat brains or find someone you can breastfeed on. Am I hearing this correctly?
Tommy Wood: Yeah.
Tim Ferriss: I’m just kidding.
Tommy Wood: Are those the only two options? I’m not sure.
Tim Ferriss: I’m kidding. Oh, wait, I forgot about the fish. I forgot about the fish, yeah.
Tommy Wood: Or you could eat some fish. Optional third. Then we also know that DHA in particular, but also EPA, these are both the long chain omega-3 fast acids, they’re important precursors for various signaling molecules that are important as it pertains to brain function, but also recovery from brain injury. So —
Tim Ferriss: What is an example of a signaling molecule?
Tommy Wood: Yeah, so actually a lot of the various molecules that have various functions in our body activating receptors, turning genes on and off, are derived from different fats. And so in this setting, the ones I’m thinking about, are called like resolvins, maresins, protectins, that are derived from these unsaturated fatty acids. And so neuroprotect in D1 is one that people are very interested in, it’s being tested as, you know, you give it exogenously after different brain injuries. We’re not at a point where I would recommend that people take it, but that’s something that’s being studied right now. And neuroprotection D1 is derived from DHA. In the setting of brain injury, these resolvins and protectins seem to be really important for regulating the immune response, in particular switching off the immune response. The immune response is important, but we also need to be able to switch it off.
And that’s probably part of the role that they’re playing. When you look at long-term omega-3 supplementation, there was a study that was done in football players, where they randomized them to different levels of DHA across the season, and they found that those taking one to two grams of DHA a day saw less of an accumulation of a marker of brain injury in the blood, called neurofilament light, across the season. The thought being that all these small sort of subconcussive impacts that the kids experience on the field is generating this sort of low level of injury that accumulates across the season, and omega-3s or DHA seem to protect against that. So all of those to say that if you want to maintain brain function, and we see if you’re omega-3 deficient, you’re at higher risk of dementia, cognitive decline, that’s dependent on other things like methylation status, but it’s going to be an important component of maintaining brain structure and function.
So I think that kind of level, one to two grams a day on average, at least this is going to — you know? If you get two or three good servings of seafood a week or a reasonable supplement, that’s going to be probably enough to consistently hit those levels.
The other part of it is that your body will actively sequester extra up to a point. So when people are talking about different forms of DHA, like should you take your omega-3s as a phospholipid form or a triglyceride form. And the triglyceride form is more common in seafood. The studies that look at these over long periods of time, what happens is if you consume a lot of the triglyceride form from seafood, your adipose tissue is used as a storage place. So it cycles through the adipose and then it gets released and the brain can use it afterwards. So that probably requires you to spend periods of time where you’re accessing your adipose tissue, right? You’re not constantly eating. So exercise or periods of fasting may help you access that depot, but that depot allows us to then use these other forms of DHA that can sort of accumulate on our bodies over time and then we use them as we need them.
Tim Ferriss: All right. I’m wondering if there’s anything else, and it may end up circling back around as well, but is there anything else related to omega-3 specifically that you’d like to comment on? And I could be hallucinating here, it’s not just AI that does it, but omega-3, does that have — oh, no, it was B complex, which you’d brought up before perhaps. Or maybe there is an interaction with omega-3 and homocysteine.
Tommy Wood: Yes.
Tim Ferriss: I’m trying to figure out where homocysteine fits into the picture with respect to cognitive health.
Tommy Wood: Yeah. So there absolutely seems to be this interaction between omega-3 status and B vitamin status, particularly the B vitamins that are involved in methylation, so they affect the level of something called homocysteine. And this is something you can get a blood test for. And those who have inadequate B vitamin status or inadequate methylation status, have an elevation of homocysteine. There have been multiple trials that happened two or three decades ago, maybe even in the last decade, where people thought, “Oh, omega-3s are going to be the answer to dementia prevention, or B vitamins and homocystine are going to be the answer to dementia prevention,” and then they would give people B vitamins or omega-3s and then they didn’t see much of an effect.
What we found out later, I mean, the scientific we, was that both are required in order to see benefit. So this was probably first seen in the VITACOG trial, which was run by David Smith at Oxford, and they found in individuals with elevated homocysteine, so that was a level above 13, giving B vitamins to reduce homocysteine significantly improved rate of brain atrophy and cognitive function, only in those who had an adequate omega-3 status.
And the same thing was seen in the B-Proof trial subsequently, and then the opposite, which was seen in the omegaAD trial where they gave omega-3 fatty acids, but they found they only saw benefit in individuals who had a low enough homocysteine. It’s thought to be because if you want DHA to be in a membrane in a cell in your brain, it needs to be attached to some kind of phospholipid, right? Fats don’t just float around, they’re part of these phospholipids that sit inside the cell membrane. And that requires it to be attached to a head group, these head groups are usually derived from choline or an ethanolamine, although those can be converted from one to the other. And in order to do all of that kind of biochemical attaching and placement, requires methylation. It’s very methylation dependent. So it’s thought that in order for DHA to do its job, you need adequate methylation status so that all those processes can run. And if you only have one or the other, then you won’t see benefit.
Tim Ferriss: Got it. Yet another reminder for long-term listeners, this will come as no surprise, but you’ve got to get blood tests, comprehensive blood tests, and really track this stuff with trend lines over time. But that’s a much longer conversation, but suffice to say, you need the orchestra, right? Or you need multiple legs of the stool.
Tommy Wood: Yeah. Yeah.
Tim Ferriss: It’s not just one leg of the stool.
Tommy Wood: Mm-hmm.
Tim Ferriss: All right. So let’s maybe return to, I’m going to use a term that’s a little dangerous to throw around, but kind of first principles or fundamentals maybe is a better way to phrase it. I’m terrified as many people are of this thing called Alzheimer’s disease. And you could throw in dementia, cognitive decline in general, right? And conversely, very interested in extending health span. I’m not totally convinced that we’re going to get to 150 years, 200 years —
Tommy Wood: Yeah, me neither.
Tim Ferriss: — like all the tech billionaires might want to have us believe, but it does seem, certainly if I look at my own health span, kind of local maximum right now for myself, there’s just capacity right now compared to prior generations, I feel very good about it. So I feel like I can extend that runway. And cognition for me is just one of the most, maybe the most important pillars of that. Because having seen multiple people disintegrate cognitively, they don’t just lose their ability to remember. They basically lose their identity, right? They lose their ability to emote. It’s a loss of the self. I mean, it’s a death before death almost in a way. So really would love to do anything possible with the right risk benefit ratio, to avoid it. But fundamentals. Should we talk about, I’m going to fuck this up, Auguste Deter, Auguste Deter? Deter? How do you say this name?
Tommy Wood: Auguste Deter, I think.
Tim Ferriss: There we go. Yeah. All right. Who is this person? Because I’m guessing most folks will not recognize the name. Certainly I didn’t recognize the name. Hadn’t seen it until I got a couple of notes from you, prior to hopping on.
Tommy Wood: Yeah, so Auguste Deter, or if you read some of the original papers, Auguste D, was Alzheimer’s index patient. So Alois Alzheimer, that Alzheimer’s disease is named after, was a psychiatrist in the early 20th century, and he took a particular interest in individuals who had sort of rare or unusual cases of presenile dementia. So what now most of us call Alzheimer’s disease, which is sort of a late onset dementia or what was called a senile dementia, which just meant that it occurred after 65 years old, that was not what Alzheimer studied. He studied unusual dementias where people who were quite young in their 40s or 50s experienced significant cognitive decline and dementia, and Auguste Deter was one of them. He then, after studying them as a psychiatrist or working with them as a psychiatrist, after they died, he then looked at their brains under a microscope.
So he was the first person to see amyloid plaques, tau tangles, that are now sort of pathognomonic. They’re like what we consider to be required as part of Alzheimer’s disease. But it’s just interesting that what we have now is not what he studied. So over time, people thought that the brains of individuals who had this sort of early onset Alzheimer’s or these early onset dementias that Alzheimer’s studied, and those who have these late onset dementia that we now call Alzheimer’s disease, those brains looked very similar under a microscope, so they were kind of lumped together. Although we do still have two kind of broad forms. The early onset Alzheimer’s, which is usually a single genetic mutation in something like a precinct gene or the amyloid precursor protein gene, that then creates a picture that’s much more like what Alzheimer’s studied, or the late onset Alzheimer’s, which is what most people think about when they think about Alzheimer’s disease is probably somewhere between 95 and 99 percent of cases of Alzheimer’s.
And there is a genetic component to risk, but it seems to be much more tightly tied to lifestyle and the environment and other lifestyle factors that we have some control over, hopefully. And the reason why Auguste Deter is interesting to me is because I don’t think she actually had Alzheimer’s disease as we would now think of it. So there have been groups that have taken sections of her brain from Alzheimer’s old collections, and they’ve done genetic studies, and she didn’t seem to have any of the genes that cause early onset Alzheimer’s disease, or any of the mutations that cause early onset Alzheimer’s disease. She wasn’t an APOE4 carrier. I think she was 3-3, if I remember correctly. So she didn’t have any of the genetic risk factors. And so what caused this and caused this so young, I think she was in her 50s, is still actually unknown.
There have been some recent retellings of the story. Some people think that she may have had neurosyphilis, and neurosyphilis actually causes amyloid accumulation, it looks very similar to Alzheimer’s disease.
Tim Ferriss: Neurosyphilis, meaning she had syphilis and she just —
Tommy Wood: It got into her brain.
Tim Ferriss: Got it, mm-hmm.
Tommy Wood: Yeah. And that can look very similar under a microscope, especially 100 years ago or more than a hundred years ago when we just sort of first starting to look at brains under microscopes. And then others suggested that it could have been more psychiatric. Nutrient deficiencies, certainly very common, could have been just like the other components of her environment. She was by all accounts like a downtrodden housewife that maybe didn’t get much engagement or stimulation or wasn’t particularly well treated at home, and that could have sort of precipitated it. And we don’t actually know, but many of these things, it just seems interesting that it’s probably quite likely she didn’t have Alzheimer’s disease at all.
Tim Ferriss: Wild. All right. So I’m going to take this in a few different directions, and as per usual, turn it around to be self-serving for yours truly. But I’m going through some of the notes that I had for our conversation and I’m sure I will have mentioned this in the bio and intro at the very top of this show, but I have this bullet in front of me and I just want to make sure this is something you feel is defensible. 45 to 70 percent of dementia is preventable through lifestyle. Is that a defensible statement?
Tommy Wood: Yes. As far as we think it can be defensible.
Tim Ferriss: Yeah. I’m not trying to put you in the hot seat. I’m just saying, I don’t know where that number comes from.
Tommy Wood: So I can tell you where that number comes from.
Tim Ferriss: That sounds great, right? That seems like a ray of sunshine and a pretty gloomy possible conversation where people think you’re just like, “Okay, there’s genetic determinism. You got this thing and you’re screwed. If you have a bunch of it in your family, you’re also screwed, et cetera.” But it seems like there’s a lot you can do to right the ship for a period of time. Okay. So where does 45 to 70 percent of dementia is preventable from lifestyle? Where does that number range come from?
Tommy Wood: So 45 percent comes from the most recent edition of the Lancet Commission Report on Dementia Prevention, which is overseen by Professor Gill Livingston and brings together all these different experts in dementia and its risk factors. And they sort of scour the research for observational studies and then as much as possible, interventional studies. So a lot of it is epidemiological data. Looking at different risk factors that have a consistent relationship with dementia risk. And then, you do these sort of statistical calculations to look at something called population attributable risk.
Which is essentially saying, if I eliminated this risk factor entirely from the population, what percentage of dementias would I expect to no longer happen? That’s essentially what it means. And all of these different percentages add up to 45 percent. So it’s a couple of percent for smoking, it’s 7 percent for a low level of earlier education. It’s like a percent for alcohol. Then there’s hypertension, hearing loss — or sorry, high blood pressure. Hypertension is the fancy medical word. High blood pressure, hearing loss, obesity, low physical activity.
And all these different percentages add up to 45 percent. There are some things that were on that list or that aren’t on that list that I think should potentially be included. So like sleep loss or poor sleep and insomnia is not included. Late life physical activity was discussed in the report but was not included even though there seems to be some good evidence there. So actually that suggests that there may be more than 45 percent that are preventable. And there are other studies, like there was one big study done from the UK Biobank data by Professor Jin-Tai Yu that estimated that up to 72 percent of dementias were preventable.
If this was going to happen, this would require a complete societal overhaul because a lot of this risk comes from low socioeconomic status, low educational and work opportunities, like all these other things that are kind of baked into societal risk for dementia. But others are things that we have more control over, like level of physical activity, whether we smoke, whether we drink. So some is directly under our control. That’s probably something like 15 to 20 percent, maybe more.
And some is kind of driven by these maybe bigger kind of societal risk factors. But if you did all of that and we managed to completely change how everybody lives and all of these risk factors, the idea is that maybe even up to three quarters of dementia cases could be entirely prevented. Now, that’s very different from saying that I could guarantee that you will not get dementia, right?
That’s not the same thing. We’re talking about this stuff at the population level. And I have to say this because if I talk about physical activity or sleep or nutrition, and these are really important for dementia risk, somebody will always say, “Well, my family member did all that stuff and they still got dementia.” And so we’re talking about probabilities. We’re not talking about, I can definitely guarantee that somebody will avoid dementia, but I think we can definitely say you can stack the deck massively in your favor through a whole variety of actions that should decrease risk long term.
Tim Ferriss: All right. So part of the reason that I make this very self-interested is because I’m self-interested. The other part is that I think the personal is very easy for people to concretize for themselves so they can interrogate how they’re behaving, what they might do differently, what they might add, what they might subtract. So let me tell you some of what I am observing and then some of what I’m doing. And I would love for you to identify or maybe speak to things that are low hanging fruit or like reasonably accessible that are missing, right?
All right. So a few things. Lots of folks in my family currently who I’m caring for in one way or another deteriorating very quickly with what has been called Alzheimer’s — again, kind of a tricky diagnosis, not sure how much they’re actually looking at, whether it’s beta amyloid, tau or anything else, but certainly in some cases, these blood relatives are APOE33. So I’m like, “Huh.” It also raises the question of, is there an undiagnosed infection? Maybe it’s an STI. Who knows? I don’t know what the answer is to that.
I mean, it’s kind of another line of testing perhaps. And so, I’ve been trying to do a few things for myself, recognizing that if someone starts to really show obvious symptoms that can’t be easily explained away in their 70s, let’s just say, the process probably started, what, decades earlier? I mean, things have started, like the cars have started to pile up, the machinery has started to break a lot sooner. So it would seem like the earlier you intervene with better lifestyle changes, et cetera, the better off you’ll be.
So I’ve got the fasting and the ketogenic diet and all of that stuff, which I do regularly. They’ve got the exogenous ketones, which like you, I use sparingly. I don’t use them all the time because particularly like before this conversation, I took 11 milliliters of a ketone monoester. But I think once all is said and done, it’s basically 51 percent, 1,3-Butanediol. And I have some concerns around 1,3-Butanediol specifically in chronic use or at sufficiently high doses, say 30 plus per day.
So I tend to use it for special occasions like this, toast, have a glass of champagne, have some exogenous ketones and off to the races. All right. So there’s the ketone piece, which I think is non-trivial. There’s the — I would say for the most part, avoiding crazy glucose spikes all the time. Occasionally I’ll have Christmas, sure, had a bunch of cookies. Who cares? It’s Christmas. It’s fine. Had a bunch of pie. But I have a CGM on right now. I had a continuous ketone monitor on at the same time for about 28 days.
I’m really interested to look at all of that, but I’m generally following like a slow carb diet or Mediterranean style diet. I am getting enough omega-3. I know that because of fish intake and also when needed supplemental intake. I do seem to be a poor methylator. So I’m taking B vitamins, L-methylfolate, all of that stuff. Tracking blood once a quarter. So I’ve got super comprehensive stuff on that side. Zone three training, I do find it as boring as watching paint dry. Even when I’m listening to a podcast or watching a Netflix mini-series or something.
But probably doing two to three sessions a week, let’s call it 30 to 60 minutes, walking every day, lots of walking and we’ll come back to that because actually, I can’t resist. We probably will come back to it, but walking 4,000 plus steps a day reduces dementia risk 25 percent optimal, 10,000 steps daily, and then reverses hippocampal shrinkage, two percent increase versus expected one to two percent decrease. That’s the bullet that I highlighted. And then, weight training a couple of times a week. I could keep going. I’m not going to bore people to death with this Dr. Evil life story.
But I will say that I’ve also wanted to get a snapshot of what things look like. So I’m going to be having a call. I won’t mention the company by name because I haven’t done all of my due diligence. They have some scientific advisors who I think are very credible, but have done brain MRI. I’ve done the blood draws, the DNA tests, everything else, because I’m APOE34. And looking at the brain MRI, I mean, I’m a muggle, right? So I probably shouldn’t be allowed to sort of grab the wheel when driving on the MRI reading.
But I wanted to look at the data. It seems like, and who knows how defensible this is, but my MRI predicted brain age based on hippocampal volume, et cetera, et cetera, et cetera, is 46 instead of 48. So I wasn’t thrilled about that. I’m like, “Well, all right, not sure what else I can do. Maybe a flood dose of ibogaine.” That’s pretty interesting data around that from Nolan Williams, but not something I would recommend to most people, including myself. So there’s that. Did a whole battery of cognitive testing through this startup.
Now that came in at brain age of 20 years predicted, 28 years younger than your chronological age, but you can kind of beat the test. There’s some gamification, so I don’t know how heavily to weigh this, right? So brain age of 20 years, man, sounds great. There are certain aspects that are harder to game, like reaction time testing. Okay. So I had like 267 milliseconds basically versus 406 milliseconds. Okay, great. There could be some training effect, like learned training effect, but then there’s like number span, focus.
I won’t bore everybody with that, but word pairs, names, and face pairing. With mnemonic devices, if you train yourself, you can really sort of game the test. And TBD on like proteomics, I’m getting all sorts of stuff drawn to try to get an accurate baseline of where I stand now so that I can measure all of the effect hopefully of these interventions over time.
What would you say are like, there are 20 things I could mention, but like here are three or four that I would also pay attention to.
Tommy Wood: So first, a couple of comments on all the stuff that you mentioned about what you’re currently doing. I’ve already mentioned that I think that there’s a lot of promise for ketones. I’m not sure that ketones necessarily have to have a place in prevention and I’m not sure that you would necessarily need them from a prevention standpoint. There are some reasonably good data. So like the medium change regulatory work from Stephen Cunnane’s lab, is quite compelling in the Alzheimer’s disease taking MCT oil seems to increase acetoacetate uptake into the brain.
This is associated with improvements in cognitive function and this is overcoming what looks like an energetic deficit in individuals who have Alzheimer’s disease. And this is something that, again, is one of those things that are pathognomonic. We think that we see this and this is kind of like part of the picture of Alzheimer’s. We see that like this is Alzheimer’s.
Tim Ferriss: Yeah. Can I pause for one second?
Tommy Wood: Yes.
Tim Ferriss: Real quick, don’t lose where you are. We’re talking about MCT oil. Number one, if people want to play with MCT oil, be close to a bathroom when you start. And if you combine it with double espresso and creatine, definitely have some depends around. The second is the ketogenic diet for me, just to briefly provide a little more context, is also for its, I think, plausible anti-cancer effects and just kind of all cause mortality plus mental acuity. I just think a lot faster when I have more metabolic flexibility with something like intermittent fasting.
That’s another thing I do a lot of, where my body has just got the machinery to produce ketones. But yes, I hear you. Okay. MCTs.
Tommy Wood: So the thought being here, right, there’s a difference between what you find works really well for you versus what the listener thinks they should have to implement for themselves. And so, I’m now going down the road of why I don’t think we all need to be in ketosis to prevent dementia. So I think from a therapeutic standpoint, it seems to be beneficial overcoming this energetic deficit that we see in Alzheimer’s disease, particularly early Alzheimer’s disease, or maybe it’s easier to overcome earlier on.
And one of the ways we look at this is with something called a PET scan, right? So you do an FTG PET, you give a labeled glucose molecule, you inject that, you see how much gets into the brain in individuals with Alzheimer’s disease, less glucose is getting into the brain. Now, we’ve traditionally come at it from the point of that glucose can’t get in, right? There’s some kind of metabolic disease, instant resistance. This is where the idea of type three diabetes has come from, insulin resistance in the brain, that glucose isn’t getting in.
But a PET scan cannot differentiate between the glucose can’t get in versus the brain isn’t asking for that glucose in the first place. And there are actually some very nice studies that looked at brain activation and glucose uptake in response to cognitive stimulus in individuals with Alzheimer’s disease. And what they see is that yes, at baseline, there’s less glucose being taken up into the brain of individuals with Alzheimer’s disease, but if you stimulate that brain cognitively, it can take up glucose just fine so that you get into the range of a normal healthy brain in early Alzheimer’s disease.
Once you get to like advanced stage dementia, it’s too late. But at that early stage, I think part of the reason why we’re seeing less glucose uptake is because those parts of the brain are less active because we’re just not using them as much. And just like glucose uptake into the muscles, which is demand driven, right? You work your muscles, they ask for more glucose, they take more up. The brain seems to be the same, at least early on. So I think we think a lot about the supply side, the energetic supply side, but I don’t think we think enough about the demand side.
How do we create energetic demand in the brain such that we are maintaining glucose uptake, maintaining energetic state, and then doing that also maintains all the metabolic machinery that you really care about in terms of long-term function.
Tim Ferriss: Can I just muggle translate for a second?
Tommy Wood: Yeah.
Tim Ferriss: All right. So if I’m hearing you correctly, this is something I’ve chatted with Dominic D’Agostino about, but I’m wearing this CGM, right? So I’ve got this device on my arm that tells me what my glucose levels are at any given point in time with whatever, three minute sampling or something like that. You’ve got to calibrate that with a fingerprint, by the way, folks. But if I eat a meal and then I don’t go for a walk, my glucose spikes and I might conclude, “Wow, my muscles are really not accepting glucose.”
My muscles are bad at accepting glucose, but that’s not actually true in my case, right? If I go for a walk or I do some light exercise, I guess it’s like GLUT4 transporters or whatever, get all jazzed up and help that glucose to be better disposed into muscle tissue, right? And like you said, in the case of the brain and people referring to Alzheimer’s as type three diabetes, it’s like, “Wow, the brain can’t use glucose,” or it’s very bad at using glucose. But if I’m hearing you correctly, the additional question that they should be asking is, is it just that or is the brain not asking for glucose, right? The equivalent of the GLUT4 transporters, right?
Tommy Wood: Yep.
Tim Ferriss: Is the brain basically offline? It’s a car up on blocks, but if you take it down, yeah, it’s going to use gasoline just fine. So if that’s the case, I guess it’s just a call to action for more stimulation of the brain. And when I was first just coming across your notes that you sent prior to this conversation, I went on ChatGPT and I was like, “What are the most glucose intensive activities for the brain?” And they gave me a bunch of mental exercises, which isn’t exactly what I was looking for, but I could have prompted it better.
And it said, “But even still, the sort of improvement or increase might be plus, less than 10 percent in terms of the total.” And then I was like, “Well, are there other activities such as physical activities that might increase glucose uptake in the brain?” And it gave me a whole list, but rather than regurgitate that, are all types of stimulation created equal or are there some sort of 80/20 analysis like, okay, there are some tools that are better for the job.
Tommy Wood: Yeah. So when looking at this purely in relation to glucose uptake, those data don’t exist, right? So I’m going to have to extrapolate further than that. And I think that’s important because a decrease in glucose uptake is just a signal that that area of the brain isn’t as metabolically active, which means we’re not just not using it as much at the simplest level. So then if you think about various activities that we could use to stimulate the brain, which do seem to be protective in various different ways, both they can enhance cognitive function in the short term.
And then protective against dementia in the long term. Actually, this ties very nicely into the comment that I was going to make about your physical activity routine, because this is where I think some things could be layered on.
When you look at the different physical activities or exercise and how they affect the brain, different types of exercise affect the brain differently. So you certainly need a smorgasbord of all of them to kind of get a global support for the brain. But something that seems to be particularly beneficial is coordinates of exercise or open skill exercise, plus or minus things that have a navigational component.
And these are essentially sports or activities where you’re constantly having to respond to the environment and adapt. That’s what makes them open skill rather than closed skill or unimodal exercise like going for a jog or sitting on a bike or something like that. So when they compare sports or activities that have the same amount of physical challenge, but a different amounts of cognitive challenge because of the open skill nature, you see greater benefits in terms of brain structure, improvements in cognitive function.
Tim Ferriss: And open skill just means high level of unanticipated variety or variety. What is it?
Tommy Wood: So both. So it basically has a greater amount of complex motor skill required. Some of it can be learned. So dancing is one example, right? So because you learn the steps of a dance, but some —
Tim Ferriss: Single strongest activity for dementia prevention. Am I overstepping there?
Tommy Wood: Yeah, probably. So if you look at physical activity and the effect that it has on cognitive function and also —
Tim Ferriss: Or one of mental health.
Tommy Wood: Yeah, but in terms of both mental health, so studies in depression, as well as studies looking at different activities that people do and the risk of dementia, their risk of dementia, and studies where they randomize people to different types of activity, including dance, dance seems to have the highest sort of effect size compared to other types of physical activity. But there’s multiple components to dance, right? So you have to learn the steps, but there’s also a social component, there’s a music component, right?
All these things are probably part of the magic source together, but open skill sports also include board sports or ball sports or team sports where you’re having to react to the environment and other people around you.
Tim Ferriss: Do you say bull sports like rodeo? What are we talking?
Tommy Wood: No. Ball.
Tim Ferriss: Ball. B-A-L-L.
Tommy Wood: B-A-L-L.
Tim Ferriss: Awesome. It’s not going to be good for the TBI to get people on top of bulls, but okay, got you.
Tommy Wood: I think bull sports would probably be good if you could avoid the TBI, actually probably right up there. Similarly, martial art is also good as long as you don’t get punched in the head a bunch or kicked in the head a bunch —
Tim Ferriss: Or choked out too much.
Tommy Wood: Or choked out too much. So these — beyond the physical strain that these exercises have, they seem to have an additional aspect of requiring reaction speed, challenging processing speed, learned complex motor skills, those — they seem to have an outsized effect in terms of cognitive function. Something else, just to — this is kind of an aside, but just based on the physical activity component, when you’re looking at more aerobic or even like closed skill, unimodal, running, cycling kind of sports.
The benefit seems to be intensity dependent. So yes, if you’re not doing anything, then going for a walk and walking a certain number of steps a day is going to be great, beneficial, decreased dementia risk, absolutely. But looking at hippocampal structure and function, for instance, which you mentioned, right? You’re talking about measuring your hippocampus on an MRI scan. Higher intensity activities seem to be better.
So probably the longest study where they ever did something like this, they had people, this was an Australian study where they had people do the Norwegian 4×4 protocol, three times a week for several months.
Tim Ferriss: My God.
Tommy Wood: And so for anybody who doesn’t know what this involves, it’s four sets of four minutes on a treadmill at 85 to 95 percent of your maximum heart rate with four minutes rest, you do that four times. It is miserable.
Tim Ferriss: I mean, that’s like, pretend like you’re being chased by wolves through the snow for four minutes. And then take a four minute rest and then do that. Yeah.
Tommy Wood: Four times.
Tim Ferriss: Yeah. Okay. Right.
Tommy Wood: But they saw significant improvements in hippocampal structure and function that were maintained for several years after the end of the trial.
Tim Ferriss: Several years.
Tommy Wood: Several years after trial.
Tim Ferriss: So a few months and then sustained for several years.
Tommy Wood: Yeah. I think they followed them up for five years after the end of the trial.
Tim Ferriss: That makes it much more interesting.
Tommy Wood: I think a lot of this is driven by lactate. So when we talk about the various things that support the brain through exercise, we often talk about BDNF, brain derived neurotrophic factor, which has increased with exercise. But the BDNF that you can measure in the blood, that’s produced by the muscles during exercise doesn’t really get into the brain very readily. Most of the BDNF we have in the brain is produced locally and it’s actually driven by things like lactate. So lactate does get into the brain.
The more lactate you have in the blood, the more it gets into the brain. And then that acts as a histone deacetylase inhibitor that activates the blood and the BDNF ketones do the same thing. Osteocalcin, which is released when we sort of load the bones structurally, it’s released from bones, seems to do something similar. So generating lactate seems to be beneficial — probably because one of the things it’s doing is it’s generating more BDNF that then is associated with improvements in hippocampal structure and function.
So as long as you’re doing sports that have some high degree of intensity, so you’re regularly producing lactate and then, either in the same sport or separately doing these sort of high skill, high reaction time, open skill kind of sports, that’s probably going to be beneficial from an exercise standpoint.
Tim Ferriss: I’m still completely stuck on the three times a week, basically VO2 max training, right?
Tommy Wood: Yeah.
Tim Ferriss: For a few months. Is a few months like three or four months, or how many months was it?
Tommy Wood: The study was either six or 12 months. I can’t remember the intervention period. It was one or the other.
Tim Ferriss: And with durable effects over a follow-up period of five years.
Tommy Wood: Five years.
Tim Ferriss: Something like that.
Tommy Wood: Yeah.
Tim Ferriss: That is a great investment. That makes it a much more compelling sales pitch for me. And like I’ve done plenty of VO2 max training in the past, but it’s not necessarily fun, right?
Tommy Wood: No.
Tim Ferriss: I mean, I will say, if you can, again, avoid getting your arms snapped, exhibit A right here with my elbow surgery, but if you can avoid the breaking limbs and getting choked out too frequently, something like jiu-jitsu is actually fantastic because you might have three to five minute rounds and then, you take a break for a round and then you go back in and chances are, depending on who you’re rolling with, it’s going to be pretty intense. Obviously, it depends on how competitive the gym is, but the durability is just remarkable. That is really, really, really, really interesting.
Now, is the threshold for sufficient intensity, I imagine it varies tremendously from person to person, depending on lactate threshold, right?
Tommy Wood: Yeah.
Tim Ferriss: But like for you, do you need to do something approaching the Norwegian 4×4 to cross the threshold sufficiently in your mind or does something less suffice?
Tommy Wood: Yeah. The problem with having just one — I mean, it’s one very good study, but just having one study on this is that we get really focused on the protocol, but I think that anything that is regularly producing, you’re getting above your lactate threshold, you’re generating significant — several millimoles of lactate. I don’t think people need to measure it, but if you’re getting six, seven plus, something like that, you’re definitely going to be in that range.
Tim Ferriss: Is there something, like people use a talk test, for instance, Peter Attia talks about this for zone two training, where you can kind of have a conversation and be labored short sentences, but you don’t really feel like it, as an indicator that you may be roughly sort of in zone two. Is there an equivalent for that range of lactate?
Tommy Wood: Not that I know of.
Tim Ferriss: 10 percent from puking into a bucket.
Tommy Wood: Yeah, it’s definitely going to be like misery related. So if I think about a lot of the training that I did as a student, I was a rower. And this is something that —
Tim Ferriss: Brutal. You love misery.
Tommy Wood: Actually, I don’t love misery enough, which is why probably I wasn’t as good a rower as I could have been. But there are lots of protocols where you’re doing relatively short sprints with relatively long rest periods that still generate large amounts of lactate. And so in studies where they’ve done this, you’re talking about 30 seconds flat out on a bike or a rowing machine with several minutes of rest times six, eight, 10 rounds. By the end, you can generate a lot of lactate without having to do something continuously for several minutes at a time.
I was just reading that one of the favorite training protocols for one of the world champion rowers was 45 seconds, flat out, completely flat out on the rowing machine, within six minutes of recovery, but doing that several times. And then at the end, you’re generating several millimolar of lactate. So I think anything like that, that’s going to get you in that zone, it just requires maximum effort for even just like 20 to 40 something seconds, even with several minutes break in between, you’re going to be hitting that.
Tim Ferriss: So I imagine the gold standard, do you have some guy in a lab coat with a clipboard who pricks your finger or something and does these blood draws to determine the millimolar concentration of lactate? Is there a breathable option as there is with ketones, right? Where you can measure acetone through something that looks like a breathalyzer as opposed to a finger prick for BHB? Does anything like that exist and make it a little —
Tommy Wood: No, they’re working on continuous lactate monitors just like you would have — and some people do sort of have those, because they’re right near being commercially available. So some people do have access to those already. But equally, I would argue that it doesn’t matter that much. Just like go and do something really, really hard for a short period of time and do that a few times over and do that relatively regularly. That’s probably enough majoring in the minors that you need to do to get that benefit.
Tim Ferriss: Sounds like my sled assignment. I do love my sled pushing and pulling. You can definitely wipe yourself out with that stuff.
Tommy Wood: Okay. All right.
Tim Ferriss: Without necessarily the impact of me trying to run from wolves on a treadmill or something. Okay. So I do want to take a brief commercial break, but it’s not for any sponsor. It’s just to mention that, and then we’re going to kind of dive straight back into the programming and discussion. But you have a book that is coming out shortly called The Stimulated Mind. It goes through all the stuff we’re talking about and a lot more. People should pick it up, that’s Dr. Tommy Wood, obviously, but The Stimulated Mind. There’s so much horseshit and charlatanism floating around out there in the world of anything related to cognition and memory. It’s part of the reason — segue is a little awkward, but I was like, that’s part of the reason I wanted to have you on is not to highlight necessarily that, but the antithesis of it, which is someone with real clinical expertise, research credentials, who is also a practitioner. It’s like you walk the walk.
And I wanted to ask you, you mentioned supplements earlier, and of course everybody loves to hear about supplements. But what are some that may not be on the usual list of suspects, so to speak? One, I would love to hear you speak to is CDP choline. People might not think of xylitol as a supplement, but certainly you could argue that maybe there’s a place for it. Do you want to add anything to that and just expand on those?
Tommy Wood: Sure. I can expand on those. I think that the supplements that we have the best evidence for they start with those core nutrients that we could get from the diet, but if we don’t, then we definitely should supplement. So we’ve mentioned omega-3s, B vitamins, especially those involved in methylation. So that’s vitamin B12, folate, which is B9, riboflavin, which is B2 and then B6. Vitamin D, obviously critical. Iron supplementation, particularly if people are anemic. So that requires a whole assessment for why are you anemic in the first place, but often particularly more common in women. And many of the symptoms that women may experience around perimenopause are associated with inadequate iron status. So getting your iron status checked and addressed is really important. Magnesium, certainly critical as well.
If we’re thinking about other things that do seem to have both an acute and long-term benefit in terms of cognitive function, then all the kind of antioxidant polyphenols are very interesting, particularly those that come from berries, but related ones in coffee, tea, on the skins of roasted nuts and seeds, they have similar effects. And so you mentioned choline, and right at the beginning when we were talking about omega-3s, I think choline is critical because of its importance as a head group for fats to be attached to in membranes. That’s maybe one of the reasons why it’s important for the brain. And various estimates suggest that we’re becoming increasingly choline deficient as we stop eating things like eggs and liver, which are our richest sources of dietary choline. But there are randomized controlled trials in two different settings that we’ve talked about already. So one in older adults already experiencing some degree of cognitive decline where supplementing with CDP choline, which is also called citicoline, seems to improve certain aspects of cognitive function.
And then again, after traumatic brain injury, there are meta analyses that show that supplementing with CDP choline can improve some neuropsychological outcomes, in particular after TBI. So I think most of us can probably get choline from the diet. But in some of these cognitively degraded states, we might call them something like 500 to 1,000 milligrams a day of choline seems to be beneficial.
Tim Ferriss: Do you take it or do you just get it from eggs and salt?
Tommy Wood: I get it from eggs and liver. And some seafood, sardines have some choline in. As do some whole grains, like oats have some, quinoa has some, so all of it kind of adds up.
So I don’t supplement the choline. I do supplement with creatine. I don’t have the perfect trial that creatine is going to prevent dementia, but I think we’ve seen enough interesting data across depression. Again, sleep deprivation —
Tim Ferriss: Sleep deprivation. How many grams do you take daily? What’s your standard daily dose?
Tommy Wood: I take 10 grams every day.
Tim Ferriss: Single dose or divided, doesn’t matter?
Tommy Wood: So I take it all in one go in the morning. There’s some evidence that suggests that once you get above five grams, you probably start to saturate creatine uptake transporters, so maybe you don’t take all of it up. But the reason why I take it all in one go is because I remember to take all of it in one go. Another reason is that I find creatine to be quite cognitively stimulating for me. So you took your ketones. I took my creatine before I got on this call.
Tim Ferriss: I took five grams of creatine too.
Tommy Wood: And so if I take creatine later in the day, I don’t sleep as well. It’s very noticeable for me, but that’s not the case for everybody. Some people take creatine and they don’t notice the cognitive effect. It doesn’t affect their sleep, so it’s very different from person to person. And so those are the reasons why I just take it all in one go in the morning. But especially if you’re going to take over 10 grams, 20, 30 grams, you’re probably best splitting it up into several doses so that you absorb more of it.
Tim Ferriss: Yeah. Or 30 grams at one go also is tempting the gods to smite you with a really, really bad bathroom situation.
Tommy Wood: So yeah, a lot of people do mention GI side effects from creatine. I think some of that is due to the quality of the supplement that you’re taking.
Tim Ferriss: Yep, I agree.
Tommy Wood: So if you’re taking like Creapure Creatine Monohydrate, that’s what most studies that have tested creatine have used. And there was actually a systematic review meta analysis that just came out that found that across all the studies they could find compared to placebo creatine, didn’t have any additional GI side effects. But also those studies use high quality creatine. Also, not all those studies use 30 grams. So you could certainly get to a point where you’re going to start to have GI effects based on those.
Tim Ferriss: Yeah. I think it also has to do with the fact that my polypharm in the morning when I’m just getting booted up, it’s like I might be having the coffee plus the creatine plus the sardines. Yeah, there’s a lot going into the cocktail of potential disaster, which you do acclimate to. Quick question before I forget, on lactate. Is there any argument to be made for anything that you would ingest or otherwise put into your body, not to avoid doing the intense exercise but to increase the amount of lactate that you uptake into the brain? Or is that something that people have looked at or is that just risky business and to be avoided because you’ll end up in like — I don’t know, like some type of acidosis or some other problem?
Tommy Wood: So people have looked at exogenous lactate itself, usually as lactate salts, just like people have looked at ketone salts. You can bump up blood lactate a little bit, but similar to ketone salts, you don’t get nearly the increases you do with other compounds. You don’t need to do anything to increase brain uptake of endogenous lactate because the brain will generally just take up as much as you’ve got, similar to ketones.
Tim Ferriss: Yeah, I think I misspoke when I was asking the question. I guess it was just increasing the amount of circulating lactates, so your brain just sucks it up like a vacuum.
Tommy Wood: Yeah. No, I think you can make plenty of lactate yourself. So another way to do it, blood flow restriction is another great way to produce lactate with low load. And there were some studies where — well, they have them do leg presses, but like sets of 20 leg presses wearing blood flow restriction cuffs, but that will get you up there as well. Again, several millimolar of lactate. It’s not fun.
Tim Ferriss: I think I’d rather do the Norwegian 4×4. Yeah. Oh, wow, that’s intense.
Tommy Wood: So that’s another way to do it. So if you, for whatever reason, don’t want to do sprints on a row machine, you can probably get up there with some blood flow restriction under low load and high rep. But no, I don’t think there’s anything that I would take to increase lactate, just because you can make it so easily yourself.
Tim Ferriss: All right. So I want to hop on the low flow restriction because I have — what make and model do you use? What’s your kind of tool of choice for the BFR stuff?
Tommy Wood: I use the B Strongs. So they have —
Tim Ferriss: Excuse me?
Tommy Wood: The company is called B Strong.
Tim Ferriss: B-E Strong?
Tommy Wood: No. Capital B Strong.
Tim Ferriss: Okay, got it.
Tommy Wood: I have no real —
Tim Ferriss: Affiliation.
Tommy Wood: I have no affiliation with them other than I know some of the guys who work there, but I paid for my device myself. So it has leg and arm cuffs, but it comes with like a Sphygmomanometer. One of those blood pressure things to kind of pump it up to get the pressure. And those are the ones I use.
Tim Ferriss: Yeah, nice and simple. I’m testing a few different ones right now. So when you travel, people think of exercise as this thing that involves potentially all sorts of machines and you need your kit. There can be a lot of excuses or things that people imagine as obstacles that are not in fact obstacles. So talk to me about your exercise when traveling with blood flow restriction. What does it look like?
Tommy Wood: So as my wife calls it, I have my gym in a bag, which I take everywhere I go when I travel. And it is a set of blood flow restricting cuffs and a set of bands. I use the Black Mountain products bands, which come with handles. And I like them because they come with a lifetime warranty. I break them and snap them all the time and you just email them and be like, “Hey, this broke.” And they just send you a new one and they cost 40 bucks or something like that, so super cost-effective.
Tim Ferriss: Can I pause you for a second?
Tommy Wood: Yeah.
Tim Ferriss: Just for people who are not looking at Tommy, you’re freaking gigantic. You look gigantic. You’re wearing a very thick sweatshirt and I can still see your pecs moving around for God’s sake. What are your dimensions here? Not to turn you into like a Playboy Playmate or something.
Tommy Wood: So I’m 6’2″. I’m usually 220 pounds. I usually hang out somewhere around 12 percent body fat.
Tim Ferriss: Yeah, strong unit. Okay. The reason that I brought that up is not to flirt with you, although I’m not against that.
Tommy Wood: Oh, I appreciate it. I’m not against it.
Tim Ferriss: No, the reason I wanted to bring it up is people might think there’s somebody out there who’s like an internet keyboard jockey on Reddit who’s living in a basement and squats 135 and is like, “Oh, that guy must be some pencil neck dweeb.” And it’s like, no, actually not. He’s pretty big. And yet you can get, sounds like a decent workout with bands that cost 40 bucks and blood flow restriction. How’s that possible? What do you do?
Tommy Wood: And when I travel, because I’m usually at work, conferences, I’m doing podcasts or whatever, like I don’t have two hours to go to the gym, which I like to have if I’m at home. So I might do 10 to 15 minutes and you put on the cuffs, legs and arms, I’ll do some lunges, like body weight lunges, squats, presses, pushups, and then bicep coals and tricep extensions, and that’s probably it. So a pretty standard protocol, which is essentially in three to four minutes, you accumulate somewhere between 75 and 100 reps. So 30, 20, 20, 20, or 20, 15, 15, 15, 15, something like that, with 30 seconds of rest in between. Try and do one body part at a time, but you can superset them if you’re kind of short on time. That’s it.
And kind of to your point, when we moved into this house, this was now eight years ago, I built my own gym here. But for a long period of time, I didn’t have a gym and I was working from home and all I had was bands and BFR cuffs. And then it wasn’t even the B Strongs. It was like these really cheap ones that kind of look like something that somebody would use to kind of like draw your blood.
Tim Ferriss: Trainspotting, yeah.
Tommy Wood: Yeah, exactly. It looks like a tourniquet to tie up your leg if you’ve blown off your foot. And again, they cost like 20 bucks. They’re probably not the best. But anyway, so I had some of those and some like 40 buck bands and that was all I used to work out for like four or five months. And I didn’t lose any muscle mass or strength. I just got straight back into it afterwards. So you can maintain and gain pretty well as long as you have to do some hardware. BFR can be a little bit painful if you sort of push it, but also very, very safe. It’s been used in rehab, right? All these other things that frail images.
Tim Ferriss: Just for people who are like, “What the hell are they talking about?” I’ll use an analogy. This isn’t exactly what’s happening. But imagine you had a small belt, tiny belt that you put around your upper arms under the shoulders, right at the top of the biceps, let’s just say keep it simple. And then I guess close to the hip on the legs?
Tommy Wood: Yeah, right up in the leg.
Tim Ferriss: And you’re partially occluding blood flow. So you’re not totally cutting off blood flow, but you’re making it a lot harder for blood to get to your arms and your legs.
Tommy Wood: It’s mainly blood to get out.
Tim Ferriss: Blood to get out, okay.
Tommy Wood: Yeah. You’re not compressing the arteries where the blood gets in. You’re stopping the blood from coming out.
Tim Ferriss: The venous return.
Tommy Wood: Yeah, exactly.
Tim Ferriss: Okay, got it. Yeah, and the net effect is if you’re like Arnold Schwarzenegger and you’re like, “Ah, the pump, I feel like coming.” Yeah, if you want to take that to a 20X extreme and feel very, very, very uncomfortable, BFR is a great way to do it. And again, for people who are like, “Oh, come on man, I squat 315 or whatever.” I’m guessing you probably squat at least 315 or more. And what do you squat? I’m curious now.
Tommy Wood: As of a couple of years ago, 405 is my best squat, better deadlifter than I am a squatter.
Tim Ferriss: What do you deadlift? What’s your PR for deadlifting?
Tommy Wood: 550.
Tim Ferriss: Yeah, that’s up there. All right. And I think you would probably agree, if you put somebody in leg cuffs and you’re like, “Yeah, do proper lunges like knee to the ground and go for a 100 yards and come back.” I don’t even think most people could do that, but it’s just like, you’re going to feel it. You are absolutely going to feel it.
Tommy Wood: Yeah.
Tim Ferriss: All right. Gym in a bag. We’ll link to all this stuff in the show notes as well. So I want to list off a couple of things here and then talk about — we can keep bouncing around a lot. Well, on the supplements, I’m going to kind of cut this short and we’ll put things in the show notes, but the periodontal health, mouth health and dementia, the connection there, hence the use of xylitol. Whether that’s the gum, Epic, KaiGum, or air purifiers, mouthwashes. We’ve got all this stuff. So I’m going to link to that in the show notes just in the interest of time and certainly feel free to chime in.
I wanted to talk about cognitive stimulation. So we spoke about dancing earlier. Could you speak to language learning and music? Because I’m realizing, I think accidentally I might have really helped my brain a lot early, which is great as a surprise. But also have next to me an ohana ukulele, which was gifted to me, that has basically just been gathering dust. And after doing prep for this and then looking into it, I’m like, “You know what? I should spend a couple of minutes a day just screwing around with this.” It seems like a great use of time, but could you speak to music and language learning?
Tommy Wood: Yeah. So this actually, if we include dance, this comes back to something that we started talking about earlier, which is what are these experiences or what are these activities that you can do with the brain that kind of maximally activate it or increase glucose uptake. And there was a really interesting study that came out recently called Creative Experiences and Brain Clocks. And what it did was —
Tim Ferriss: Creative Experiences and Brain Clocks.
Tommy Wood: Yeah.
Tim Ferriss: Okay.
Tommy Wood: So I’ll break that down, there’s different components. So kind of like when you did an MRI scan for your brain, and all those other tests you did, there are various different ways that people can sort of like estimate how old the brain looks, right?
Tim Ferriss: Right. And I don’t know if that’s hugely BS or not. I don’t know. Yeah.
Tommy Wood: It’s a bit of both.
Tim Ferriss: Yeah.
Tommy Wood: But in this context, I think it’s kind of useful because when you think about what happens to the brain as it ages, there are a few things that happen. The structure changes, different parts of it gets smaller, you lose volume, but then functionally also changes. The different networks that we have in the brain that have different functions and activities, they become less discreet and they become more distributed. So you get less of these kinds of very functions, specific, tightly knit networks and connections. And then everything just becomes a little bit more sort of like loose and different areas of the brain get connected together and there’s a bit more of a mismatch. You get this increase in entropy. Initially what we call it is brain entropy. It’s not as discreet. And entropy then decreases again as we get towards the end stage of dementia, just because there’s not much going on in there, unfortunately anymore.
Sorry, that’s the best way I could put it. And so when you look at different ways to quantify how old this brain looks, one way is to look at the structure and the connectivity of the networks and how discreet they are. Things like the frontier parietal network, the salience network, the attention network, like these parts that are really important for executive function, focus, attention, all this kind of stuff. And they tend to lose function as we get older. And the easiest way to do this is with EEG, so electro encephalogram where you basically measure the electrode activity in the brain. And so in this study, what they did is they took a whole bunch of different studies and they looked at these different creative experiences. So one was tango dancing, one was language learning, then there was musicians, they had artists, and they also had video gamers, and they had an interventional study where they had people learn the video game.
And it was StarCraft was the game that they used just in case anybody was wondering. Although if we’re talking about video games as a cognitive stimulus, the one that has the best evidence is Super Mario 3D World, just in case you were interested. Lots of studies with that actually. And what they did is that they compared amateurs to experts, and then they also looked at the effect of an intervention where people actually were trained in this thing. And as you increase in expertise in these different creative, complex arts, you see improved structure and discreteness of these really critical networks that are susceptible to aging as we get older. But the effect was similar in tango dancers versus those who are bilingual versus those who are artists versus video gamers. So there’s some core effect of these complex multisensory stimuli that require us to gain significant expertise and skill in order to perform them that seem to have this broad effect.
So part of this is probably because we’re training our brains to be able to focus and learn, and then part of it is just like the actual engagement in this complex task. And so when you look at, say, languages, two very good colleagues of mine at the University of Washington, Andrea Stocco and Chantel Prat, they study individuals who are bilingual. And what they see, they’ve done this from both measuring brain activity and different types of cognitive function, and then trying to model what’s actually going on. And what it looks like is that those who grew up bilingual perform better on tasks requiring executive function. So things like response inhibition, which is you kind of want to do something but you stop yourself just in time. Normally when I talk about it’s like, you know when you have these thoughts of like, “Oh, well, what would happen if I just opened this window and jumped out?” Or you think something and you stop yourself just before you say it, because it’s a really bad idea because it’s like your boss —
Tim Ferriss: How do they test that? Are you using like a Stroop test as a — I’m just throwing something out there.
Tommy Wood: Yeah, So often it’s like a go no-go task. So you’re presented with different stimuli and it’s whether you react to it or not, but like a Stroop is partly an example of that, which is where people don’t know what Stroop is.
Tim Ferriss: You should explain it. Yeah.
Tommy Wood: Yeah. So you get shown words that spell a color and they are also colored. And then you have to respond based on whether the word spells the color you’re looking for or is the color you’re looking for. And so it like requires you to juggle these multiple things. And so yeah, they use tests like that. But basically it seems that because you spend your entire life having to suppress one language while you activate another and then move back and forth, your brain becomes better at suppressing these different — but at the same time, interestingly, it seems that you become less good at other things. So none of this is good or bad, but people who are bilingual seem to be less responsive to what’s immediately happening around them in the outside world. And that’s probably, again, just because of how their brains have adapted to these different stimuli.
But you do see that those who grew up bilingual have a decreased risk of dementia, or if they do get dementia, they get it later. But you also see improvements. If you train in a language, even like using an app on Duolingo, they’ve shown that, in older adults, you use Duolingo, and of course you have to actually move through it, not just stare at it for 30 minutes a day, but that you see significant improvements in executive function and you see the same thing with music learning. So there is something to these complex, very human kind of skills that have these carryover effects into these kinds of core components of cognitive function.
Tim Ferriss: Yeah. I’d never heard about the response inhibition with subjects who are bilingual. But it might explain in a totally separate battery of cognitive testing that I did, which was much more rigorous, I think, than what I did a few days ago. My digit string memorization, despite all my mnemonic trickery, is very bad because it’s only flashed for a second and then you have to do your best. If you gave me a bunch of time, I could use all my trickery.
But if it’s just a flash and it’s kind of relying on, I guess, my hardware, then I’m very bad to the point where people might have some concern, but I’ve always been like that. Conversely, with something like this, there was a test that was pretty much exclusively the Stroop test, but it had a few things that were very similar. And I was like, I’m exaggerating, but tense standard deviations outside of the norm. I was so much better that they were like, “Why are you so good at this? We’ve actually never seen something like this.” And it could be studying all these different languages. I don’t know, maybe. Who knows?
Tommy Wood: So do you know what? I’m actually the same, and we’re kind of convincing ourselves that this is real, just because it’s the case for us. So I often do cognitive function tests on people we work with in studies and that kind of stuff, and we do this full battery, all the things that you mentioned. And on every test, memory, all these other things, I’m just like, I’m perfectly average. And you always think that, oh, I’m so smart, so therefore I should be at what X standard deviation. But no, I’m perfectly average on everything except for response inhibition tests or the Stroop test. And I also grew up speaking multiple languages, so maybe that’s the thing. We don’t know.
Tim Ferriss: Which languages do you know?
Tommy Wood: So I speak Icelandic because my mom’s Icelandic, so half my family were in Iceland. And then I lived in Germany and France when I was a kid for various periods of time. And then I did my PhD in Norway and I taught in the medical school, so I had to learn Norwegian so that I could teach Norwegians medicine.
Tim Ferriss: Wow, that’s hardcore. Yeah, there’s quite a few. And for people out there who are like, “Well, I wasn’t raised bi or trilingual.” I didn’t really even get started until I was 15, 16. Always assumed I was very, very bad at languages for reasons that were mostly related to the schooling and not to any inherent ability. But I’m also thinking about tango as an example, because I spent a lot of time doing tango. I’m not sure if you have any familiarity with this chapter in my life, but in 2004, basically spent like six to eight hours a day doing tango in Argentina. And competing ultimately going to the world championships and all this craziness. But you have the physical component, but like you said, it’s actually a pretty complex cocktail. And in my case, sure you have the dancing, but you also have Spanish. I was learning Spanish at the same time. And then you have the music, and I’m wondering if studies have been done looking at the effect of listening to or having to track different types of music versus producing music. Has anyone looked at that?
Tommy Wood: Not as much. Certainly frequent music listening is associated with a lower risk of dementia and cognitive decline as much as you can get rid of all the sociological pieces of that. There are some studies looking at training adults in musical theory, which requires actually listening to music and then pulling out the different components that seem to be, again, associated with similar benefits to say learning to play a musical instrument. So I think even some of that attentive listening and actually engaging with the music as a listener seems to have some of the benefits in addition to producing the music yourself.
Tim Ferriss: Yeah, because with dance, obviously, if you actually have a hope of dancing well, you have to listen very, very carefully to the music. And in particular, you could have choreographed dancing, but what interested me about tango which I didn’t realize in advance of getting to Argentina, is that the vast majority of it, tango de salon is improvised. So if you’re going to compete in that particular style of tango, salon tango, you don’t know what music’s going to be played and then they just serve up whatever the songs happen to be. So you’re not only responding to the music, but you’re memorizing music. And in any case, makes me want to give back to Argentina.
Tommy Wood: Maybe it’s all that time off, that’s why your hippocampus has been catching up with you.
Tim Ferriss: Yeah, exactly. Oh, add that to my litany of complaints. So I wanted to highlight something. You’ve mentioned this. I don’t think we need to spend a lot of time on it right now, but sensory loss, hearing, vision, getting aids/surgery as soon as possible since those seem to be so correlated to increased risk or onset of dementia. I want to mention two things and then I’ll let you rip. The second one is — now, I’m kind of paraphrasing here, but error detection triggers adaptation. So the importance of failure, because with a lot of the hand wavy, pseudo-scientific games and this, that, and the other thing that are sold for supposedly helping people with memory cognition, et cetera, a lot of them don’t seem to check that box. So maybe if you could speak to the sensory loss and then the kind of error detection and defining that and the importance of it.
Tommy Wood: Yeah. So there are several studies that suggest that sensory loss, particularly vision loss through cataracts and hearing loss through age-related hearing loss, presbycusis are associated with an increased risk of dementia and that this risk is reversible. So, if you have cataract surgery, then that increased risk is no longer there. And if you get hearing aids, again, that risk is no longer there. Only of those two randomized controlled trials have only been done with hearing aids and they only showed significant benefit in those who were at an increased risk of dementia for other reasons. So, like poor health, cardiovascular disease, these other things.
So, it may be that it’s exacerbating other underlying risks, but equally we can think about two broad reasons why sensory loss might lead to cognitive decline and why often as people get older, they’re like, “I don’t want to get hearing aid because then I’m old,” right?
Tim Ferriss: Conceited defeat.
Tommy Wood: Yeah. And so, this happened with my mom actually and she recently got hearing aids and I encouraged her. I was like, “As soon as there’s a thing that you need, you should get it.” And it’s had a dramatic effect on our quality of life. And so, we know that if you lose an input to an area of the brain, that area of the brain is going to decrease function as a result, right? It’s no longer being used and with the process of allostasis or constantly adapting to the demands that are placed on you, that part of the brain is going to diminish its function. So, that’s part of it. But I think a bigger part is that when you lose senses, you no longer engage in the world in the same way that you did previously.
You go out of the house less, you socialize less, you do less tango dancing because you don’t feel like you can engage with it in the same way. So, I think there’s a lot of benefit from recovering lost senses that’s not the same as, so if you are born or if you never had sight or you never had hearing, that’s not associated with increased risk because you learn to engage with the world in other ways, right? So, it’s the loss of that engagement that I think is important. Then the error part, the easiest way to think about this is that if we’re trying to improve function and structure of certain parts of the brain, that allows us to have greater reserve, greater total capacity.
And therefore if we do lose some volume or some capacity as we get older, we have more to lose. So, we’re less likely to get to the point where we have significant deficits. In order to drive improvements in structure and function, we need to drive these processes that we call neuroplasticity, right? New connections, new branches, all the supporting machinery, the other cells that are necessary. We think a lot about neurons, but there’s a whole bunch of other cells and stuff in your brain that are really important as well that are part of this response to stimulus.
But to drive neuroplasticity, you essentially have to have a difference between capacity and expectation, right? So, the best way to uncover that is with mistakes or errors. If you —
Tim Ferriss: Kind of like muscular training to failure or —
Tommy Wood: Exactly. Yeah. So, if you don’t ever get to the point where you’re no longer capable of doing the thing that you want to do, nothing needs to change. You can already —
Tim Ferriss: Yeah, exactly. Your body doesn’t need to adapt.
Tommy Wood: Exactly. Yeah. So, that’s essentially it. And this is what becomes important in dancing, learning languages, learning music, is that you’re having these opportunities to fail to get beyond your current capabilities and that’s what drives the processes of learning and plasticity.
Tim Ferriss: What else do you have in your personal regimen of non-negotiables? Obviously, you’re lifting weights, you’re doing your blood flow restriction torture every once in a while. I don’t know if you’re much of a ballroom dancer.
Tommy Wood: I was a field raver in my youth, but I was never much of a ballroom dancer.
Tim Ferriss: Get that man some glow sticks. So, a big part of the reason I got elbow surgery was to get back into rock climbing, which I think is just a phenomenal, phenomenal sport for mental and physical development. I mean, it’s just a kinesthetic puzzle on a wall. I mean, and was really inspired over the last two years seeing people in places like Colorado, Idaho, Utah, where I’d go into these gyms and you see people in their ’60s and ’70s who are doing stuff that I can’t even imagine doing physically. And they meet a couple times a week and I was like, “Wow, okay. If you can have that kind of longevity in this sport, that seems like a great investment.” Plus I just really, really enjoy doing it.
But what are some other non-negotiables, right? If you look at all the possible things you could do, all the things you do and you’re like, “All right, these are the things that are meaningful and that I stick with consistently, what falls in that bucket?” Because a lot of people will get these like 27 things, 47 things you can do to improve your brain health lists or whatever. And even if they want to do all those things, there’s no way they’re going to. So, there’s a question of sustainability or adherence as well, right? So, yeah, what are some of the other non-negotiables for you?
Tommy Wood: Yeah. So, I think the one that we haven’t talked about that really as non-negotiable is sleep.
Tim Ferriss: Yeah, let’s talk about it.
Tommy Wood: Yeah. And I think this is the major thing that’s missing from these studies looking at dementia prevention as a risk factor. And I think inadequate sleep, really seen in so many studies now that’s associated with increased risk of dementia. So, that’s something that I very consistently make sure that I get enough of. That’s like the one thing that really is non-negotiable. I don’t mind if my diet gets a bit crappy for a few days or I don’t mind if I can’t get to the gym for a few days. This stuff integrates over months and years, but if I can only focus on one thing, then sleep is really critical for me.
But I will say one thing that I noticed a lot was that historically, I used to really get in my head about my sleep, and I know this is going to be the case for many people who have tracked their sleep or used wearables or thought about the importance of sleep, right? And so, something that changed recently, particularly because I spent a lot of time looking at the research, and this also affected me at home because my wife was like, “If you don’t sleep and then you don’t get your coffee, I don’t want to be around you because —
Tim Ferriss: Picked up a moderate heroin habit?
Tommy Wood: A lot of it was honestly self-induced because I thought I didn’t sleep well, therefore I’m not going to function well. I’m going to be grumpy, like all this kind of stuff, right? And we know that this is influenced by outside factors, this is influenced by our own thought processes. There are studies that have shown this, randomizing people to be told by their wearable they didn’t sleep well even though when they slept just fine, right? And what you see in the short term, long term, sleep is critical, right? Absolutely. And any sleep you can get more than you are having now, the better, right? So, if you sleep six hours a night, you can get six and a half, great. Don’t think that you have to sleep eight hours.
If you can get an extra half an hour, that’s amazing. But in short periods of time, actually sleep deprivation doesn’t have as much of a negative effect on cognitive function as we think. And this is just important so that we can go about our day-to-day lives and perform well when we don’t sleep well. So, what happens
Tim Ferriss: Especially when you have a chalkbag full of creatine at your desk.
Tommy Wood: So, the creatine helps, but equally like we travel, we have kids, all this kind of stuff. Sometimes, you’re just not going to sleep well. But in short periods of time over a few days, what happens is that processing speed slows down, but accuracy doesn’t. So, the quality of your work is just as good. It just might take you a little longer and mood is affected much more than performance. So, actually we don’t perform less well. We just feel more grumpy about how we performed. And so, actually, knowing this, I then just completely changed how I approached my sleep. So, if I didn’t sleep well, I’m like, “Do you know what? I’m actually going to be fine.” And then it turns out I am fine.
So, that’s like, yes, sleep is critical, but how we think about these things I think is really important. And then another thing, so like important factors are going to be like avoiding excessive alcohol, don’t smoke. But then two things that you’ve mentioned we haven’t touched upon fully, I’ll like briefly talk about. One is air quality and air pollution, which is a significant risk factor for dementia. A lot of these studies are quite recent looking at say wildfire exposure and things like that. But even living near roads, like in the short term is associated with greater cardiovascular risk, higher blood pressure, which you can improve with having an air filter.
And of all the different like metabolic type risk factors for dementia, high blood sugar and high blood pressure are the two most important, lipids and other things are important as well, but those are consistently the highest risk factors. So, managing blood pressure is really important. And if so you live near somewhere with a lot of air pollution, then air filters certainly seem to help there. And then oral health was the final one. So, the reason I say this because I appreciate that I’m British and I’m going to tell you you should go to the dentist. So, historically when I lived in the UK, I did not go to the dentist very, very frequently.
And actually, the first time I went to the dentist here in the US, I had this one metal crown from back when I was a medical student and my dentist looked at it and he was like, “You didn’t get that done in the US.” That was his first comment. But gum disease, so gingivitis, especially if it advances the periodontitis, is significantly associated with an increased risk of dementia. This is probably both due to an increased like systemic inflammatory effect, plus those bacteria can get into the bloodstream. They’re found in atherosclerotic plaques in heart disease. They’ve been found in amyloid plaques in the brain. So, treating gum disease is really important, whatever that requires.
And that’s why I mentioned xylitol to you because there are several studies showing that xylitol gum or xylitol mouthwash can improve the oral microbiota, decrease some of these like cavity and periodontitis causing bacteria like Strep mutans and Porphyromonas gingivalis. So it’s just like a really low risk kind of thing. There he is with this gum.
Tim Ferriss: A low risk in my pocket.
Tommy Wood: A low risk thing to consider. And I don’t think they’ve looked at it by APOE4 genotype, but things that have an anti-inflammatory effect or decreased inflammatory burden seem to have an outsized benefit for those who are APOE4 carriers. And so, gum disease would obviously be one of those that’s worth keeping an eye on.
Tim Ferriss: That’s part of the reason not to keep banging on this drum because I know it’s not the shoe that fits everyone, but that’s another reason for my fascination with ketones, just remarkably anti-inflammatory on a couple of different levels. So, for folks who might be wondering, and we’ll put these in the show notes as well, air purifiers, do you mind if I just read from this email that you sent to me?
Tommy Wood: Sure.
Tim Ferriss: Because of course I’m such a stickler. I’m like, “What exactly make and model?” So, yeah, I’ll just read from this. The blood pressure study I mentioned — this is I equals Tommy — use the HealthMate, that’s one word. JSPR is good, that’s J-S-P-R. As are most of the Blueair, one word, Blueair models tailored to the size of the room. The Coway, C-O-W-A-Y Airmega is a good budget option. So, we’ll link to all these in the show notes. This is one, God with travel, such a pain in the ass, although I think it was James Nestor who wrote the book Breath, who was giving me just some horrifying quantified self data related to looking at like CHO2 concentration in various hotels around and airplanes and so on.
And so, I don’t think he’ll stay in a hotel that has sealed windows. I think it’s part of his policy because —
Tommy Wood: Yeah, high CO2 really negatively impacts sleep. So, like lots of people in a small room that’s not ventilated, that can definitely negatively impact sleep. So we always have a window open or something for that reason.
Tim Ferriss: Anything else that you do for sleep besides not becoming too orthorexic about it and like freaking out on the wearables and stuff, which is a real thing for sure. So, besides recognizing that you’re going to be fine, humans have been dealing with this for a long time, what else would you say, right? I would imagine there’s things people have probably heard like keeping the temperature, whatever it might be, 65 to 70 degrees Fahrenheit, et cetera. Other things that you find particularly helpful?
Tommy Wood: Yeah. So, things that have helped me a lot, I stop work before dinner. I don’t do work after dinner unless I really, really have to. And that helps a lot because I find I ruminate a lot more if I do work late into the evening. A basic shutdown routine, I put on the blue light blocking glasses, they’re probably just placebo at this point, but I put them on and my brain is like, “Oh, it’s bedtime.” And then I read fiction before I go to sleep. Quite a recent purchase was an eight sleep, which has been amazing because I tend to get quite hot when I sleep, so that’s helped a bunch. So, I just helped stay cool. And then I wear an eye mask, which I really like for blocking out light.
And there were also some very nice studies on that. One of my favorite studies looking at eye masks, you ever see this one where in the control group, they had them wear a Zorro mask? So they were still wearing a mask, but the eyes were cut out.
Tim Ferriss: No.
Tommy Wood: And this was during the summer when light would come in early in the morning, would disrupt sleep and they saw significant improvements in cognitive function in those wearing the regular eye mask versus like the Zorro mask.
Tim Ferriss: The Zorro?
Tommy Wood: Yeah, it was hilarious. I think that’s probably my list.
Tim Ferriss: Got it. I’m going to ask you something specific about sleep, but just because I have it in front of me to ask you, vitamin K2, do you supplement K2 or do you get it from something else?
Tommy Wood: I do generally supplement just like a few micrograms a day, maybe 15 or 20, but that’s mainly because it comes with my vitamin D that I was supplementing particularly in the winter. In the summer, I get plenty of sun exposure on bare skin, but in the winter, can’t do that in Seattle. But I also don’t mind a little bit of natto or some fermented foods that would have K2 in as well. So, don’t need to supplement, but certainly
Tim Ferriss: Stinky spiderwebs. If anybody likes the sound of stinky spiderwebs, try natto, N-A-T-T-O. It’s the one that Japanese people like to give foreigners to watch the face. Some people like it. I can handle a little bit. I can handle a little bit.
Tommy Wood: I mean, I grew up eating rotten shark in Iceland.
Tim Ferriss: Oh, that stuff is so fucking bad. I went to this place called Hotel Ranga, I think it’s Ranga, to bring my family. My mom had always, her whole life wanted to see the northern lights. And so we went there in the middle of the winter. By the way, folks, not a whole lot of light. It’s like twilight for a few hours. That’s all you get. But there was some fermented shark celebratory day and we drove to what looked like, and I think it was a gas station, but had a restaurant attached to it and ate this fermented shark. How would you describe it?
It was like, I mean, fermented shark as you would imagine, but like eating something soaked in like ammonia, like the pungency when it hits your sinuses is like smelling salt. I mean, it’s so —
Tommy Wood: So it is ammonia. So to make Greenland shark, which is the type of shark edible, so Greenland sharks don’t have kidneys. So their tissue, just their body accumulates urea, because they don’t pee it out. So in order to make it edible, that urea has to break down to ammonia and then it becomes “edible” in quotation marks. And so, it is ammonia that you’re tasting, but it’s like it’s got the texture of tuna and the taste of a really, really, really strong blue cheese that you peed on.
Tim Ferriss: I will say, I wasn’t really hankering for a return trip to that particular gas station to eat fermented shark, but watching my brother try to eat it was one of the most entertaining moments I’d had in a long time.
Tommy Wood: So, you know you’re supposed to alternate shark with Brennivín, which is Icelandic aquavit. And so, like you use the shark, you eat the shark, then you use the aquavit to take away the taste of the shark, you use the shark, take away the taste of the Brennivín, and then you just continue that until —
Tim Ferriss: You just get hammered enough that you don’t care that you’re eating fermented pissed sharks?
Tommy Wood: Exactly. So, actually, I don’t mind the shark that much. There’s one thing that’s much, much worse. If you ever have a chance to try Surströmming, which is a Swedish fermented herring in a can, that is the worst thing I’ve ever put in my mouth. It’s terrible. Actually, if you look it up, there are all these YouTube videos of people who get it in the US and they open it and the smell comes and then they immediately throw up. It’s like you open the tin and you take out these rotting bones of herring that you put on bread. Highly recommended.
Tim Ferriss: Yum. All right, I know what I’m doing for New Year’s. All right. So, sleep, do you have a position on the DORAs on the dual orexin receptor antagonists because I’ve chatted with folks, including Matt Walker, who’s very credible in the space with respect to sleep research, the potential that DORAs could help with the clearance of beta amyloid, what is it? pTau217, et cetera, and possibly be of some help in preventing the accumulation of things that later contribute to Alzheimer’s. I mean, it’s not like the vote is in and it’s 100 percent, but there seems to be a couple of interesting publications around it, including in humans. Do you have a position or any thoughts on it?
Tommy Wood: Yeah. So, very quickly, we know that sleep quality and quantity affect amyloid accumulation in the brain. That can be seen over short periods and long periods. And some of that work is from Matt Walker’s lab. And he’s even done studies that show that later in life, if you can improve the amount of sleep that you get, then that’s associated with a lower overall amyloid burden. I think that some of this, we get very focused on amyloid. It’s a part of the picture of Alzheimer’s dementia, just like you said, it’s not the full picture. But I think we look at it and it’s a marker for all the things that you should be clearing out of the brain when you sleep that you aren’t, right? Amyloid is one of those things.
There are probably many other things as well. So, the DORAs have now several studies in different states within insomnia, in sleep apnea, these states where we know people are getting lower quality sleep and they certainly seem to improve that. I think that in individuals who have some kind of sleep issue, be that insomnia, something else that’s going to prevent high quality sleep, then improving that is certainly going to be beneficial. Right now, the DORAs are now the best option. Previously, people recommended trazodone, which is like, we talked previously, the least worst option because it doesn’t negatively affect sleep architecture, unlike many of the other sedatives that people might use to help sleep.
But if you’re sleeping fine, or you manage to maintain high quality sleep, as you get older, I don’t think we need to start taking DORAs to prevent Alzheimer’s because I think your sleep is probably already doing the job that it’s doing. And there are studies that show that increased cognitive stimulation in older adults improves sleep quality, or that engaging in cognitively stimulating activities helps to offset some of the potential increased risks that we would have with poor or less good deep sleep, which is when a lot of this clearance happens.
So, I think a lot of the other things that we mentioned already, physical activity we know improves sleep quality. So, I wouldn’t jump straight to DORAs, but in somebody who does have insomnia and say CBTI, so CBT for insomnia doesn’t help them, or some of these other things that we can do to improve sleep and those don’t work, and you’ve ruled out anything sinister, then I think they’re now our best option to help support sleep.
Tim Ferriss: All right. We have covered a lot. I want to know why you decided to do something very difficult, which is write a book, The Stimulated Mind. What was the driver behind this and who is the book for?
Tommy Wood: I like to joke that the book is for anybody with a brain. The subtitle is about preventing dementia, but really a ton of it is just about cognitive function and cognitive performance in general. So even people who are younger and aren’t thinking about dementia yet, although like you said, it’s worth thinking about it earlier than you think.
So I think for most people who think about how their brains work or want their brains to perform better and/or want to prevent or minimize their risk of dementia long term, it’s got what I think are the big rocks and the tactics for how to address those that we know substantially increase dementia risk, all those things we talked about earlier that contribute to those dementias that are potentially preventable. And the reason I wrote it is because I didn’t think that book really existed. People might focus on one particular area or they might focus on everything, right?
There are books on dementia prevention that are just like endless tables of blood tests and supplements and this stuff that just like most people are never going to do, right? It’s not going to be sustainable. I didn’t really see a middle ground, but equally, I wanted it to be very heavily referenced. So if people want to get into the references, I have a reference list. It’s going to be 2,000 papers, all in humans, and it’s cited in the text, right? I have like little super script citations in the text.
Tim Ferriss: You teased the subtitle a little bit. It’s a good subtitle. So, I want to give it some real estate here. So, The Stimulated Mind subtitle, Future Proof Your Brain from Dementia and Stay Sharp at Any Age. I’m looking at the Amazon page for the first time. I hadn’t looked at it. I had no idea that you know Kelly and Juliet Starrett. Those are two very close friends of mine and you got a very nice quote from Dr. Kelly and Juliet for the book. That’s fantastic.
Tommy Wood: So, I only really connected with them about a year ago, but they’ve been so, so helpful. What do you do when you wrote a book and how do you get it out there and how do you get people to read it? They’ve given me so much of their time and help. They’ve been amazing.
Tim Ferriss: Yeah, they’re fantastic. All right. So, “Dr. Wood,” that’s you, “explains that a brain that improves with age is the result not of expensive pills, far off discoveries or strict lifestyle optimizations, but rather of actions within our control, diet, sleep, physical activity, social connection, and stress tolerance.” And obviously it goes on and on. But clearly, you have a lot of very practical, specific advice that people can implement.
And what else makes this book different?
Tommy Wood: So I think those things that I mentioned make it different. I think it’s very practical and approachable, but very science driven. And if people want to dig into the references, those are available. And then I think, like towards the end, there’s all these different areas where we talked about nutrition, sleep, physical exercise I give, like how you would approach each of those things in terms of supporting cognitive function and minimizing dementia risk. But then I bring them together in a model of how I think people can implement this in their daily lives. How do I just pick one thing?
And actually, does picking just one thing help to support like the overall function of the brain? And the answer is yes, it does because when you sleep better, so say if you focus on improving sleep, you’re more sociable, you’re more likely to engage in cognitively challenging tasks. Your blood sugar improves, your blood pressure improves, right? So, just changing one area, suddenly the whole network shifts in your favor. And that’s the case from almost anywhere where you approach it. And I think that means that people are much more likely to actually start doing this stuff and realize that it doesn’t require a ton of work to start moving the needle and then these things compound over time.
Tim Ferriss: Mm-hmm. All right. The Stimulated Mind, folks, go grab a copy. Obviously, I hate when people say obviously, but I’m going to say it. Obviously, Dr. Tommy has the credentials, has the expertise, has the bonafides with respect to research in humans and has provided a lot that you can use in this conversation and a lot more is in The Stimulated Mind. So, check it out. Why on Earth is your X account called Dr. Ragnar?
Tommy Wood: So I first started blogging around the time you first started podcasting. And I remember listening to your first interviews with Don D’Agostino back in the day when I was in my PhD chair writing blog posts. But my middle name is Ragnar, so I created a website. It was Dr. Ragnar. That was initially where I did my stuff.
Tim Ferriss: So let me think about this for a second. I’m going to make myself probably regret asking this question, but does Ragnar mean anything? Because now I’m thinking of Ragnarok and if those two have any connection. Does it mean anything in particular?
Tommy Wood: So, no. So, you’re right. Ragnarok is like the final battle for Valhalla, right? And actually, there were some online gaming accounts where I used the name Ragnarok. No, I think what it means, the translation for the old Norse is like “wise counselor.” I think that was another reason why I picked it, because it was very self-important as a 30-year-old health blogger, but it was my grandfather’s name and then these names get passed down in the family. Technically, because I was the firstborn grandson. It should have been my first name, but my dad was English and it was like, “People are just going to make fun of him at school. He’s going to get bullied if he’s called Ragnar.”
It’s very cool now, because of Vikings and all these other TV shows where Ragnar now appears. But yeah, that’s —
Tim Ferriss: I mean, you could make it work, but Dr. Ragnar Wood also has a strange combo one, two to it. All right, got it. @drragnar. R-A-G-N-A-R on X for people who want to check it out.
Tommy Wood: To be honest, I don’t use X. So, you can follow me on X, but you won’t see anything.
Tim Ferriss: But people can find, presumably there’s something at drtommywood.com, drtommywood.com. So, that’s the home base online.
Tommy Wood: Instagram.
Tim Ferriss: Instagram?
Tommy Wood: @drtommywood. Again, drtommywood.
Tim Ferriss: @drtommywood. All right folks. So, you got it. Check out The Stimulated Mind. I’m a huge fan of what you do. I am going to try to improve my and arm situation with more use of BFR and bands. And is there anything else you would like to say before we wind this to a close? Anything you’d like to ask of the audience, point them to, requests, complaints, anything that comes to mind?
Tommy Wood: No. Other than if you do happen to pick a copy of the book and you do have any complaints, do send them to me. One of the reasons why I wanted to make it so that every statement that I have in the book has a citation, you can go, you can read that paper. If you disagree with my interpretation of it, I want to know. I can’t promise that I have all the answers. So, that will help me learn more. So, yeah, if you have a complaint, just tell me about it.
Tim Ferriss: All right, Tommy. I really appreciate all the time, man. This was great. Took tons of notes for myself, which is always a good sign. So, thanks for carving out a bit of time to be on the show. Really appreciate it.
Tommy Wood: Thanks so much. Thanks so much for having me. This is so much fun.
Tim Ferriss: And for everybody listening as per usual, we’ll provide copious links and show notes at tim.blog/podcast, tim.blog/podcast. And until next time, be just a bit kinder than is necessary to others and also to yourself. As Jack Kornfield says, if your compassion does not include yourself, it is incomplete. Thanks for tuning in.
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