Future-Proof Your Brain from Dementia & The Lifestyle Levers That Keep You Sharp with Neuroscientist Dr. Tommy Wood

1. Decline is not destiny. An estimated 45% of dementias are preventable per the 2024 Lancet Commission, and analyses of UK Biobank data suggest the upper end may exceed 70%. It is never too late to change your trajectory — improvements show even in people in their 60s and 70s.
2. Use the three S model. Brain health rests on Stimulus (challenging, focused learning and social interaction), Supply (cardiovascular health, metabolic/energy regulation, and key nutrients), and Support (sleep, trophic factors, and avoiding inhibitors like alcohol, smoking, chronic stress, and air pollution). Changing one factor cascades into the others.
3. How you use your brain is the primary determinant of how it functions. We are 'chronically overstimulated while understimulated' — multitasking across media trains distractibility, not deep work. Use AI and tech as an orthotic (to enhance your own effort) rather than a prosthetic (to replace it).
4. Lean into productive failure. Neuroplasticity is driven by errors and mismatches between prediction and reality. Learning new, uncomfortable skills — ideally in a supportive social context — drives measurable structural brain change even in older adults.
5. Exercise is a buffet, not a single protocol. Aerobic work and HIIT support the hippocampus and memory; resistance training supports white matter and executive function; complex 'open skill' coordinative activities (dance, martial arts, ball sports) best support overall cognition; and simple regular movement throughout the day matters too.
6. Get the basics from food first. Prioritize energy balance (avoid both chronic excess and chronic restriction), key nutrients (omega-3s, B vitamins, vitamin D, iron, magnesium, antioxidant polyphenols), and a sustainable eating pattern. Sardines and blueberries are Wood's favorite brain foods.
7. Test, then supplement intelligently. Check vitamin D (target 40–60 ng/mL), homocysteine (ideally below 10), omega-3 index (ideally above 8%), hemoglobin/iron, blood pressure, blood sugar, and lipids. Creatine (around 0.1 g/kg, roughly 5–10 g/day) is the one non-vitamin supplement Wood recommends for its broad brain benefits.
8. Mindset and self-compassion are levers, not fluff. Belief shapes physiology (Ellen Langer's work) — thinking something is harmful can make it harmful. Self-compassionate people have better health and athletic outcomes. The best dementia prevention is not isolating yourself with supplements but treating yourself well and staying connected.
9. Protect sleep as foundational. Chronic sleep under six hours raises dementia risk; relying on alcohol, antihistamines, or Ambien produces a facsimile of sleep, not restorative sleep. Don't let imperfect wearable data dictate your day — create cognitive and temporal distance from the metrics.

Why Dementia Is Not an Inevitable Decline

Rich Roll opens by sharing that dementia runs in his family and that the past couple of years watching his mother and others suffer have been devastating — both because of the toll on individuals and families and because of what he calls the inhumane way modern healthcare manages the condition. Against that backdrop he asks Dr. Tommy Wood whether the adult brain is destined for inevitable decline. Wood's answer is an unequivocal no.

Wood's logic is simple: if some proportion of dementias are preventable, then by definition we must be able to change the trajectory of cognitive function and cognitive decline in adults. He frames dementia as the terminal point of cognitive decline where a person can no longer look after themselves day to day. This was a controversial position perhaps a decade ago, but is no longer.

The strongest support comes from the Lancet Commission on Dementia Prevention, spearheaded by Professor Jill Livingston, now in its second iteration (updated 2024). Global experts statistically estimate which risk factors are causally linked to dementia and potentially modifiable, then ask: if a given risk factor didn't exist, what proportion of dementias would never happen? Summing across factors, they arrive at 45% of dementias being potentially preventable — published in The Lancet. There are additional strongly-linked modifiable risk factors not yet in their models, leading some to argue the true number could be even higher.

The Cardiovascular Connection and Why It Took So Long

Rich notes that, from a basic perspective, cognitive decline is partly a circulatory problem like heart disease — amyloid plaques are caused at least in part by lifestyle choices. Wood explains that part of our heightened concern about dementia stems from how good we've become at treating cardiovascular disease over the last 50–60 years. Because we treat heart disease better, the age-specific incidence of dementia has fallen: at 70 or 80 years old you are less likely to be diagnosed with dementia now than 20 or 30 years ago.

Cardiovascular disease is a risk factor both for vascular dementia (roughly 10–20% of cases) and Alzheimer's disease (which has a vascular component and represents 60–80% of dementia). At least 70–90% of dementias have cardiovascular risk factors as a contributor — and those are precisely what we've gotten better at managing.

Wood points to the Seattle Longitudinal Studies of the 1950s and 60s, which found that cardiovascular risk factors were strong predictors of cognitive change over time, and that more than 50% of people maintained cognitive function from their 50s into their 60s, 70s, and 80s. We now call such people 'super agers' because we assume it's unusual, but the data showed 50–60% did this even back then — findings used to help justify raising the U.S. retirement age in the 1980s. The reframing toward prevention came once we could show that treating heart disease at a population level brought down specific instances of dementia, allowing us to talk about prevention for the first time.

The Rising Burden of Dementia

Rich cites statistics: U.S. cases predicted to roughly double by 2060, from about 7 to 14 million; currently between 6.7 and 7.1 million Americans with Alzheimer's; a projected 139 million worldwide by 2050; and roughly 10 million new cases annually. Wood explains that two seemingly contradictory truths coexist — age-specific incidence has declined over the last 100 years, yet total cases are rising because people live much longer. You are less likely to be diagnosed at 75 than ever before, but more likely to ever be diagnosed because you'll live long enough.

Wood notes that projections of a doubling or tripling may be slight overestimates, partly because rising diagnosis reflects better detection. However, worsening metabolic and cardiovascular health — rising obesity and type 2 diabetes — is genuinely pushing the burden up, with high blood pressure being one of the most important predictors of dementia risk. Counterbalancing factors that have improved age-specific incidence include reduced smoking, better heart disease treatment, and expanded access to education and complex, cognitively stimulating jobs (particularly for women). He adds that GLP-1 receptor agonists, with their large effects on cardiovascular risk, blood pressure, and blood sugar, could further bend the trajectory downward if started early enough.

The Three S Model: Stimulus, Supply, Support

Wood's central framework, drawn from his background working with athletes, mirrors the stimulus-recovery-adaptation model of physical training. Just as the training stimulus is the primary driver of improved fitness or muscle (you don't get bigger biceps without doing bicep curls, no matter how many naps and protein shakes), how we use our brains is the primary determinant of how they function.

He likes the parallel between physical and cognitive performance because the principles align so neatly — meaning we don't have to choose between physical and brain health, and there's no pyrrhic tradeoff.

Stimulus

The brain needs genuine stimulus: education, skill development (music, languages, complex motor skills), and crucially social interaction, which Wood calls a primary driver of human brain evolution, development, and maintenance. He argues we are chronically overstimulated yet understimulated — bombarded by multitasking and social media that don't drive real improvement, while failing to engage in the focused, deep learning that actually builds brain function.

Supply

Once you activate a brain region, local neurons and astrocytes signal blood vessels to dilate and increase blood flow — hence the need for good cardiovascular health. The brain also needs energy (primarily glucose, but also ketones and lactate), requiring good metabolic health. Finally it needs a supply of nutrients: B vitamins associated with methylation, omega-3 fatty acids, vitamin D, iron, magnesium, zinc, antioxidant vitamins (C and E), antioxidant polyphenols from colorful foods, and structural precursors like choline and ethanolamine from eggs and whole grains.

Support

Just as you get stronger during rest rather than during training, the brain adapts during recovery. Sleep is critical — it cements and refines the synapses generated during the day through skill learning, building new structure and function visible on MRI even in older adults. Trophic factors like brain-derived neurotrophic factor (BDNF, produced during exercise) and hormones support synapse growth and neuron function. Equally important is avoiding inhibitors of adaptation: alcohol, smoking, chronic stress, and air pollution.

Why the model matters

Because stimulus drives supply and supply drives support, the elements interact — change one thing and you change many at once. Quitting smoking removes a risk factor but also improves inflammation and blood pressure and makes healthy diet choices more likely. Sleeping better improves blood pressure and makes you more social and cognitively engaged the next day. This means there is an 'in' for everyone, and a single starting change can shift the whole network in your favor.

How Priorities Shift Across the Life Course

Wood resists pure reductionism but acknowledges the most important pillar shifts with age. He also notes that the reductionist chase down the amyloid cascade pathway, while not unimportant, drew resources and attention away from these other levers — part of why prevention thinking arrived late.

In one's 30s and 40s, knowledge workers generally receive ample cognitive stimulation; their gap is on the support and recovery side — whether they ever give their brains a break, escape constant task-switching, and sleep enough. In midlife, declines in physical activity and metabolic health may become the critical component. Later in life, particularly at retirement, people are at the biggest risk of accelerated decline precisely because they lose the complex skills, learning, and social interaction that work and education previously provided — making stimulus paramount again.

Technology, Multitasking, and AI

Wood stresses these technologies aren't inherently bad — it comes down to how we engage with them. Five minutes scrolling Instagram looking at funny dogs can be a genuine mental break that enables hard work afterward; the problem arises when it triggers negative emotions (political anger, social comparison with richer or better-looking people) or when it's done for extended periods or simultaneously with other media.

Studies on heavy multitaskers show the brain adapts to the stimulus: such people have less of a multitasking cost, but the human brain still cannot give full focused attention to two things at once, so everyone does worse on both tasks when multitasking. Worse, heavy multitaskers become more distractible because their brains stop filtering peripheral information — impairing the ability to do deep work. It's a trade-off, like training to be a marathon runner versus a powerlifter.

On AI, Wood borrows a framework from his colleague Ken Ford (an AI expert): the distinction between cognitive orthotics and prosthetics. An orthotic enhances existing ability (like supportive shoes letting someone with cerebral palsy walk); a prosthetic replaces something missing. We risk using AI as a prosthetic for our brains — and we know that functions we stop engaging are lost or never develop. Used as an orthotic, AI can expand our capabilities. He cites an MIT essay-writing study: students who wrote the essay themselves first, then used AI to ask how to improve and what they'd missed, and integrated that feedback back in, performed best — because the work and engagement remained theirs.

Neuroplasticity, Failure, and Stereotype Embodiment

Wood debunks the notion that the adult brain can't learn new things. The belief that aging means inevitable uselessness has been embedded in society for over a century — retirement was popularized on the premise that by 60 you have no use to society. This produces 'stereotype embodiment theory': if we expect aging to bring loss, we stop engaging with the things that maintain function, creating a vicious cycle.

Randomized controlled trials of language learning, music learning, and physical activity in people in their 60s, 70s, and 80s show structural brain changes and measurable cognitive improvement. Learning is slightly harder and slower with age — not because the brain can't change, but because it has been optimized for your existing environment and you don't want it infinitely malleable. The key is to engage processes that drive change by truly focusing on something and 'showing your brain that it matters.'

The primary driver of neuroplasticity is errors and mistakes. We don't experience the world directly but a prediction of it, and the brain constantly looks for mismatches between expectation and reality (measurable via EEG, largely driven by drops in dopamine). Detecting an error tells the brain to form new connections. Neuroplasticity is driven by catecholamines like noradrenaline and dopamine — stress hormones — so productive learning feels slightly uncomfortable, and that discomfort is the point. The practical implication: we must put ourselves in positions to make mistakes and occasionally fail (not constantly, which is demotivating), pushing the edges of our capability. Adults hate this — fear of injury, of looking stupid, of being the bottom rung at a jiu-jitsu class — but reframing failure as brain-promoting, ideally in a supportive social context where everyone is a beginner, makes it more palatable and overlaps with Blue Zones insights about community and accountability.

Exercise and the Brain

Movement is, in Wood's words via Iñigo San Millán, 'evolutionarily baked into our genes.' Recent ancestors walked 15,000–20,000 steps a day and moved six to eight hours daily; movement is required to keep cellular maintenance going, including in the brain. Just as we engineered the food environment such that we now invent diets, and the built environment such that we invent exercise, we've engineered the cognitive environment such that we now must invent new stimuli — the next frontier.

Everyday movement and steps

Breaking up sedentary periods with 'exercise snacks' immediately boosts mood, changes blood flow to the brain, and improves cognitive function. As daily steps increase toward the equivalent of 8,000 to 12,000 (or wheelchair propulsion for those who can't walk), there's a linear reduction in dementia risk and linear increase in cognitive function.

Aerobic exercise and HIIT for the hippocampus

Brisk walking, jogging, and cycling particularly benefit memory and gray matter — including the hippocampus, which is critical for memory and especially vulnerable in later-stage Alzheimer's. A recent six-month study randomized people in their 60s and 70s into a control group, a moderate zone-two/three jogging group, and a HIIT group using the Norwegian 4x4 protocol (four minutes at 85–95% max heart rate, three-minute rest, repeated four times), three times a week for 40–45 minutes. Both exercise groups improved cardiovascular fitness equally, but the HIIT group had much greater improvements in hippocampal structure and function and did much better on learning tasks — and that benefit was retained five years later even though participants reverted to being relatively sedentary. The intensity-dependent release of myokines and exokines (like BDNF) helps explain this.

Resistance training for white matter

Resistance training particularly benefits white matter — the myelinated tissue beneath the gray matter responsible for fast connections and complex functions like decision-making and executive function (lost early in dementia). Studies using basic programs — two times a week, five or six full-body machine exercises, three sets of 8–12 reps for six months — significantly improved white matter structure and function and executive function, visible on MRI.

Open-skill coordinative exercise

Complex 'open skill' activities — badminton, martial arts, tennis, ball and team sports, board sports, and especially dancing — require learning complex motor patterns, responding to environment and opponents, strategizing, and rapidly processing information. Processing speed declines with age but is trainable. These activities best support overall cognitive function across meta-analyses, with dancing often winning out for both mental health and cognition.

Putting it together

Wood prescribes a 'yes and' buffet: move regularly throughout the day; do aerobic training that ideally has a coordinative and social component (soccer, badminton, table tennis rather than solo jogging); do basic resistance training once or twice a week; and do sprint-type intense work once or twice a week, where the real goal is generating lactate, which enters the brain and switches on BDNF production. He warns against the 'medicalization of exercise' (per Daniel Lieberman) — the false belief that citing a specific study means you must do that exact protocol. The Norwegian 4x4 is just one effective interval modality; variety matters, and acclimating to one protocol means you should change it up. Pick activities you enjoy — but not so comfortable that you never face the productive discomfort of learning something new.

Strength vs. Muscle Mass, Power, and Mobility

Wood says strength is generally proportional to muscle mass and building one tends to build the other. Muscles release factors that support the brain and are the body's biggest blood-sugar sink. At the population level, higher strength is consistently associated with lower disease risk, whereas muscle mass gained simply from carrying more total body weight isn't functional in the same way. The takeaway: strength is probably more important than mass, and you want strength that is functional and relative to your own body size — and improving strength improves muscle mass along the way.

Power — how fast you can contract and move — is lost fastest with age. Losing the fibers associated with strength and power undermines the ability to catch yourself from a trip or grab a handrail, leading to falls, hip fractures, and bed-bound deconditioning that's hard to recover from. Beyond standard weightlifting, studies show even a minute of jumping a day significantly improves bone mass, muscle strength, and power — so skipping rope or jumping in place adds value.

On mobility, Wood reassures that bodybuilding-style training and functional movement aren't mutually exclusive. For beginners, training like a bodybuilder (compound, machine, dumbbell, or band work) is the safest, easiest, and best entry point — it significantly improves strength, maintains or builds muscle, develops the type-II fibers important for power, and carries very low injury risk. The randomized controlled trial evidence for improving brain structure in older adults comes from exactly this kind of basic resistance training. Ideally it's complemented by other activities requiring flexibility, stability, cutting, jumping, and running through sports or martial arts.

Nutrition: Nutrients, Energy, and Pattern

Wood deliberately avoids endorsing any single diet, instead organizing nutrition around three interacting features: nutrients, energy, and the eating pattern that sustainably delivers both.

Energy — the bell curve and brain reserve

There is a bell-shaped relationship between energy availability and 'brain reserve' (essentially how much brain you have, where more is generally better). At the high end, excess energy — reflected in high blood sugar, high blood pressure, and central adiposity — raises dementia risk. But the low end is also harmful: data from multiple populations, including hunter-gatherers, show low energy availability is associated with smaller brains. This is highly relevant to athletes: relative energy deficiency in sport (RED-S / low energy availability) is associated with significant changes in cognition, mood, and sleep. It also rebuts the longevity-community belief that chronic caloric restriction is a font of longevity. The goal is enough energy to remain weight-stable while maintaining strength, performance, and fitness — avoiding both chronic excess and chronic restriction.

Nutrients — the great leveler

The nutrients with the best evidence for brain function are iron, vitamin D, omega-3s, and the B vitamins tied to methylation (B12, folate, B6, and riboflavin/B2 — measurable via homocysteine, which rises when these are inadequate). On top of these are antioxidant polyphenols: anthocyanins (which make berries purple), the compounds in coffee, tea, and chocolate associated with lower dementia risk at moderate intake, the roasted skins of nuts and seeds, lutein and zeaxanthin and carotenoids (beta-carotene in carrots, the pigments in peppers), and astaxanthin (which makes salmon and shrimp pink). Some of the best evidence is for dark berries/blueberries, with dozens of studies showing acute and chronic cognitive benefits. Vitamin C, vitamin E, magnesium, and zinc also recur. Wood calls nutrients 'the great leveler' — he wants you to have enough and cares much less where they come from.

Whole foods vs. supplements and nutritional dark matter

Wood prefers nutrients from whole foods. Epidemiologically, people who regularly eat seafood get greater dementia-risk reduction than those who take omega-3 supplements — likely because whole foods contain 'nutritional dark matter,' the roughly 90% of food compounds whose functions we don't fully understand (he cites ergothioneine from mushrooms as a newly studied longevity compound). Whole foods 'stack the deck.' Crucially, omega-3s and B vitamins interact: supplementing omega-3s in someone with poor B-vitamin status yields no benefit, and vice versa. This interdependence, Wood argues, is where reductionist single-supplement trials have misled us — giving thousands of people one nutrient, finding no effect, and concluding it doesn't work, without measuring whether subjects needed it or whether dependent co-nutrients were present. That said, for people who don't eat seafood, supplementing omega-3s when deficient does produce significant cognitive benefit.

Pattern — sustainability over perfection

Pattern is finding a way to reliably hit adequate energy and nutrient intake that is sustainable given your budget, access, and cultural context. There are innumerable ways to 'skin those cats.' Sustainability matters because brain health integrates over decades; people abandon supplements within a month but need lifelong consistency, so the pattern must be enjoyable and nourishing.

Overeating, Metabolic Syndrome, and Ultra-Processed Foods

Wood notes that even short-term overfeeding studies — adding candy bars or extra French toast to a Western diet for a week — produce measurable changes in mood and hippocampal/memory function in humans. Long term, this manifests as the markers of metabolic syndrome: high waist circumference, low HDL, high triglycerides, high blood sugar, and high blood pressure — all significant, measurable dementia risk factors and direct outputs of chronic excess calorie consumption. Depending on the dataset, only about 10% of U.S. adults have none of the metabolic syndrome components (three to five are needed for a formal diagnosis). Elevated LDL/ApoB is also a modifiable dementia risk factor, though not part of the metabolic syndrome criteria.

The biggest practical traps are calorie-dense, nutrient-poor refined carbohydrates and fats — baked goods, snack foods, fried foods, sweets, and sugar-sweetened sodas — engineered to be over-eaten. Wood warns against the new generation of 'health-washed' products: protein candy bars are still candy bars, keto or vegan brownies are still 900-calorie brownies, and 'low sugar' often still means energy-dense and nutrient-poor. He doesn't demonize any single food (he notes folic-acid fortification of flour since 1998 dramatically lowered population homocysteine, a benefit of processing), and occasional sugar or dessert is fine if you've handled the foundations — but the more you shift toward these foods, the harder it becomes to hit nutrient targets and avoid overeating.

Practical Food and Supplement Guidance for a Plant-Based Eater

Asked about his favorite brain foods, Wood names sardines and blueberries. A varied whole-food diet supplies structural compounds like choline and ethanolamine (eggs, oats, quinoa, whole grains) and phosphatidylserine/phosphatidylcholine (soy products), colored vegetables for antioxidants, fiber for gut health, and fermented foods (sauerkraut, kimchi, fermented dairy). He suggests most people overeat refined carbohydrates (rice, pasta) that are calorie-dense and nutrient-poor, and would shift focus toward more satiating, nutrient-dense choices.

For plant-based eaters specifically, Wood flags omega-3s, B vitamins, and protein as the nutrients easiest to miss. He recommends measuring homocysteine (target below 13, ideally below 10) and omega-3 index (above 6, ideally above 8). On protein, the updated dietary guidance has moved from the old 0.8 g/kg toward roughly 1.2–1.6 g/kg of body weight, especially as people age and face anabolic resistance, frailty, and sarcopenia — though stimulus (resistance training) remains the most important driver of muscle. Rich notes he's always eaten below recommended protein yet still gains muscle after his spring spinal fusion recovery; Wood explains protein's importance scales with context (a satiety lever in calorie-dense diets, critical in aging and frailty, and supportive of antioxidant status and recovery).

Demystifying omega-3s

Wood says scientists have overcomplicated omega-3s. The two main ones are DHA and EPA (with smaller amounts of DPA). Most quality supplements contain both. Around 1–4 grams of total DHA+EPA per day is good enough, and form (triglyceride vs. phospholipid) matters much less than people think. The shorter-chain plant omega-3 ALA (from chia seeds, walnuts) converts poorly to long-chain forms — worse in men than women on average — which is why direct supplementation matters for those not eating seafood. He advises not obsessing over ratios; the real problem is people consuming none. Once you're above roughly a gram a day, you're in a far better bucket than most, and you can verify with an at-home omega-3 index test targeting above 6%, ideally above 8%.

Mindset, Self-Compassion, and the Psychology of Health

Wood repeatedly returns to the work of psychologist Ellen Langer (so often that his editor made him cut some references). Belief shapes physiology. In one Langer study, diabetics drank identical milkshakes labeled high-sugar or low-sugar; blood sugar rose much more after the 'high-sugar' label — the stress of anticipating a spike drove it up. Generally, expecting something to be good for you yields a roughly neutral effect, while expecting it to be harmful yields a negative one.

This extends to self-perception of behavior. Studies adjusting for actual activity-monitor data show that people who believe they exercise more than peers live longer and have better cognitive function than those who believe they do less. The danger of over-analyzing health is that everyone walks around comparing themselves to an imaginary standard, perpetually feeling they fall short — a chronic state of lack that is itself a health-harming stress.

Self-compassion — comprising self-kindness, mindfulness, and common humanity — is protective. More self-compassionate athletes are more resilient and perform better over time because they understand setbacks and treat themselves as they'd treat others. In chronic disease settings, interventions that build self-compassion improve outcomes like blood sugar and blood pressure in diabetics. Wood reframes the cultural message that we must always do more and push through as the exact opposite of what creates sustainable wellbeing: acknowledge you can improve, celebrate wins, enjoy the discomfort of growth, but accept you can't optimize everything. This not only sustains the behaviors but maximizes the benefit you derive from them.

Rich and Wood agree this is perhaps the most underappreciated lever — in an epidemic of loneliness and disconnection, much population-level ill health stems from a sense of not being enough. As Wood puts it, the best way to minimize dementia risk is not to sit at home alone chugging supplements but to treat yourself well and stay connected to others, which then makes the other healthy behaviors happen almost naturally. He even frames a societal responsibility: those with the time and resources to 'biohack' are already privileged, since low socioeconomic status, deprivation, and lack of access to education and healthcare are among the biggest drivers of dementia risk.

Responsible Supplementation and Key Blood Markers

Wood's evidence-based stance: address nutrient status for nutrients critical to the brain that are commonly deficient — the majority of adults worldwide are deficient in at least one. He recommends a blood panel covering the markers below, beyond which most supplements are 'cherry on top.'

Target markers

• Vitamin D: don't be deficient (below 20 ng/mL); ideally above 30, with 40–60 a good target. Wood cautions that vitamin D is fat-soluble and easy to overdose — Rich shares that mega-dosing pushed his levels too high and impaired his sleep, illustrating that more is not always better.
• Homocysteine (for B vitamins): definitely below 13 (Rich notes 30 was misspoken in conversation), ideally below 10. If elevated, supplement B12 and folate, possibly adding B6 and riboflavin; creatine, betaine/trimethylglycine, and choline can also lower it (found in beets, eggs, meat, and fish respectively).
• Iron status: measure hemoglobin alongside ferritin, transferrin saturation, and iron-binding capacity. Women ideally above 12.5, men above 13.5 — but not too high (men above 17 or women above 16 raises suspicion of obstructive sleep apnea, since dropping oxygen overnight drives extra hemoglobin production, and sleep-disordered breathing is itself a dementia risk factor).
• Omega-3 index: above 6%, ideally above 8% (available as an at-home test).
• Magnesium: hard to test directly, but commonly under-consumed, especially by people who sweat or train heavily; a supplement is a safe recommendation and taking it at night may improve sleep.
• Blood pressure, blood sugar, and lipids (cardiovascular risk): the bulk of dementia risk sits here.

Creatine

Creatine is the only non-vitamin/mineral supplement Wood mentions in his book. It's the best-studied supplement, very safe, with few side effects, and achievable through diet (steak, salmon) at standard doses. Evidence is mounting for brain benefits: improved recovery after concussion, improved memory in older adults and those with early cognitive decline, maintained cognition during sleep deprivation, and added benefit when combined with antidepressants for depression. He invokes 'positive asymmetry' — high potential benefit with low downside beyond cost.

On dosing, Wood pushes back on social-media escalation toward 20–30 grams. A standard 5–10 grams (smaller people 5g, larger people 10g) produced benefit in rugby-player sleep-deprivation and depression trials. The widely publicized recent sleep-deprivation study used about 0.3 g/kg — which is where 20–30 gram figures come from — and brain-creatine levels rise significantly only at such loading doses. But since benefits appear at much lower doses, he isn't convinced everyone needs 30 grams. His personal approach: about 0.1 g/kg (he takes 10 g/day), occasionally doubling it when very stressed or sleep-deprived. He notes creatine is mildly alerting for him (without jitteriness), so he avoids taking it late in the day.

Sleep, Wearables, and Recovery

Sleep is foundational: it cements and refines the day's new synapses through a synergistic interplay of REM and deep sleep, supports emotional processing, and clears amyloid and other waste via the glymphatic system during deep sleep. Chronic sleep under six hours notably raises dementia risk — lower than most people expect. The healthy window is individual and shifts over time, roughly seven to nine hours (possibly six to ten); waking refreshed is the real signal.

Sleep quality matters as much as quantity. Studies measure poor quality by asking whether people take something to help them sleep — and those who do have higher dementia risk, likely from downstream effects. Alcohol creates REM-sleep deficiency; caffeine (especially afternoon) impairs deep sleep, and the common vicious cycle of afternoon caffeine plus an evening glass of wine delivers a double whammy. Ambien negatively affects neuroplasticity (animal data), and sedating antihistamines like Benadryl are anticholinergic — and regular use is associated with increased dementia risk, since acetylcholine is important for long-term cognition. Wood stresses that pharmacological sleep is a 'facsimile of sleep' — you may be unconscious without doing sleep's restorative work. For insomnia, the sleep architecture is intact; the issue is feeling unsafe or unable to wind down, addressable through cognitive behavioral therapy for insomnia (CBT-I) and sleep environment, sometimes with expert help to wean off dependence.

Orthosomnia and the wearable trap

Wood warns we've swung too far toward wearable obsession ('orthosomnia'), where the metric becomes the target rather than restful sleep itself. Wearables track sleep duration reasonably well but are poor at distinguishing deep from REM sleep — so the recovery/sleep scores built on those stages rest on low-quality data. A Langer–Lockley study manipulated clock time so people thought they'd slept more or less than they actually had; perceived sleep predicted next-day function better than actual sleep (people who slept five hours but thought it was eight showed no impairment). Other studies show fed-back wearable data — telling people they slept poorly — drives next-day fatigue regardless of actual sleep.

Rich shares that he wears a Whoop and checks it but keeps an 'arm's length relationship,' since dwelling on red scores would harm his mindset and problem-solving. Wood's advice: create cognitive distance and temporal distance from the data — you have to perform today regardless of last night's number, so review trends a week later when you can attribute a poor night to a late bedtime, an extra beer, or an afternoon coffee. With professional athletes he often has the coach, not the athlete, see the data, using trends over time rather than single readings.

Lessons from Formula One

Wood does his Formula One work through a company called Hintsa Performance, working with coaches embedded in drivers' lives (handling training, nutrition, travel, even holding the helmet and umbrella). A surprising lesson: the basics still matter most. Drivers worried about insufficient REM sleep often turn out to be spending only five hours in bed — and since REM concentrates at the end of the night, the fix is simply more sleep opportunity (time in bed ready to sleep), not exotic interventions.

Because drivers travel across the world weekly with extreme time-zone shifts, the team builds jet-lag plans, manipulating caffeine, light, sleep timing, and food timing a day or two before travel to pre-shift the circadian rhythm. An app called Phase, built by an F1 coach for exactly this, now lets ordinary people do the same. The bigger overarching challenge is that drivers are over-stimulated — complex driving inputs plus media commitments, engineer meetings, and constant feedback — so the core need, as for knowledge workers in their 20s–40s, is finding ways to truly switch off and down-regulate via meditation, breathwork, and protected downtime. Wood notes the most receptive athletes are veterans trying to extend their careers, while 20-year-olds resist meditation advice — though today's young athletes are far ahead of those of 20–30 years ago, and Hintsa's driver development pathway instills these habits early.

It's Never Too Late

For the 35-to-55-year-old who feels they've 'already cast their vote' after decades of a standard American diet, Wood's answer is that it's never too late. A Matthew Walker study found that people who improved their sleep later in life — even in their 50s, 60s, or 70s — had a lower burden of later amyloid in the brain, suggesting the damage isn't simply locked in.

Multi-intervention trials reinforce this. The FINGER study in Finland — recently replicated in the U.S. as the POINTER trial — and similar studies worldwide address cardiovascular risk, start new exercise programs (resistance and aerobic), improve diet quality, and sometimes add stress reduction. Benefits appear within six to twelve months of attending to the basics, even in people in their 60s and 70s, with the biggest gains often in those already showing some decline (short of a dementia diagnosis). Starting in your 30s, 40s, or 50s gives you potentially 20 years to change the trajectory. Wood also cites the U.S. SWAN study showing that the cognitive changes of perimenopause are worse in women with metabolic disease — meaning addressing diet, activity, and cardiovascular/metabolic risk during that transition could substantially alter the path.

Wood clarifies the headline numbers: the 70% figure comes from Professor Juntao Yu's analysis of UK Biobank data (over half a million people), estimating the upper end of preventable dementias exceeds 70%, alongside the Lancet Commission's 45%. These are population-level statistics and probabilities — no individual is guaranteed prevention — but the message is that risk can be dramatically reduced. He's hopeful the conversation is shifting, noting that the post-COVID period (long COVID and lockdown effects on lifestyle) has driven a surge of public interest in brain health over the last two or three years, with more people citing Jill Livingston's work and trials like POINTER.

Closing Message

Wood's parting message: we each have enormous control over our long-term cognitive trajectory and can dramatically decrease dementia risk even with a family history. A powerful place to start is to do something meaningful for or with people in your family or community who have been affected. And because all the factors interact, changing one thing causes the whole network to shift in your favor. Rich closes by directing listeners to Wood's book, The Stimulated Mind, for the full particulars, calling the work a vital public service given how few people are untouched by cognitive decline.