Podcast Summary: The Neuro Experience — “I Asked a Neuroscientist How to Avoid Dementia. His Answer Changed Everything | Dr. Tommy Wood”

Host: Louisa Nicola
Guest: Dr. Tommy Wood
Release Date: December 30, 2025

Overview

This episode delves into how much control we have over cognitive decline and brain aging, demystifying widespread beliefs around dementia, brain supplements, peak performance, and the most meaningful interventions for lifelong brain health. Dr. Tommy Wood, physician-scientist and author of The Stimulated Mind, challenges the inevitability of dementia and instead outlines practical, science-backed steps to strengthen cognitive resilience—emphasizing lifestyle, not expensive supplements.

Key Topics & Insights

1. “Brain Health Is NOT Destiny—It’s Modifiable”

• The Truck vs. Formula 1 Brain Analogy
  • Most people “poison their brains by treating them like trucks instead of Formula 1 cars” (00:00).
  • Dr. Wood asserts that while genetics and some uncontrollable factors exist, the “majority of cognitive decline is basically optional, were we to put everything in place, that would change the factors that affect cognitive function” (01:32).
• Aging and the Myth of Inevitable Decline
  • Contrary to popular graphs showing steady declines from youth, for most people “cognitive function can stay relatively stable from your 50s into your 80s and maybe even further” (02:20).
  • The drop in the population average is due to a subset that declines markedly, not a universal trajectory.

2. Defining Cognitive Function — Structure vs. Performance

• Difference Between Brain Structure and Cognitive Function
  • Neuroscience has focused on structure (proteins like amyloid and tau), but structure alone tells little about day-to-day function (04:42–05:18).
  • “How the brain looks under the microscope is almost completely unrelated to how that brain functioned in real life” (04:50).
• Cognition Is Individual
  • While regions like the frontal lobe (executive function) and hippocampus (memory) can be mapped, every brain is different and shaped by unique life exposures (05:42).
  • “Is your brain doing what you want it to do, when you want it to do it?” (06:30).

3. Supplements & Nootropics — Hype vs. Evidence

• Most Brain Supplements Lack Robust Evidence
  • “The vast majority are not necessary. Many of the supplements that might work tend to be core, basic nutrients… the majority of supplements don’t have a huge amount of evidence behind them” (08:38).
  • Spending $500 a month on brain supplements is often “flushing [your] money down the water” (08:38).
• Lifestyle > Pills
  • “The core functions of the brain are much better supported by manipulating lifestyle and the environment as much as we're able to. So physical activity, for example... the evidence there is much greater than, say, for most supplements” (09:25).
• Stimulants and “Smart Drugs” Are Not Magic
  • E.g., caffeine and ADHD meds may sharpen reaction time but can worsen executive function and working memory if overstimulated (10:58).

Notable Quote

“You may be improving one part of function at the expense of another. Now… that's not necessarily a bad thing. But you shouldn't think that you're sort of overall just improving everything at the same time.”
— Dr. Tommy Wood (10:50)

4. Peak Brains in Elite Athletes – Not Miracles, Just Massive Training

• Formula 1 drivers don’t have magic brains; they have extreme, targeted cognitive skill development from thousands of hours of practice and tailored recovery, sleep, and nutrition (13:22).
• Neuroplasticity means what separates high performers is “just time… skill development” (14:41).
• This applies to learning any skill—NBA players, language learners, etc. (15:00).

5. Dementia: Preventable Causes and the Power of Kindness

• Definitions:
  • Dementia = umbrella for significant loss of cognitive function. Alzheimer’s is the most common type; vascular dementia is next (16:36).
  • “Some estimates say 45%, others say maybe as much as 70%, but potentially the majority… are preventable through manipulation of diet, lifestyle and the environment” (16:54).
• Rule 5: Be Kind to Yourself
  • Chronically believing “you're not doing enough” creates internal stress, inflammation, and worsens cognitive outcomes.
  • “There are a few studies that show that thinking like that, thinking that you’re not doing enough, is actually associated with worse long term health and worse cognitive function, in fact” (17:55).
• Social Stress Physiology
  • Chronic stress (high “allostatic load”) is linked to worse brain health and mortality—even when actual behavior is accounted for (19:00–21:00).

Notable Quote

“Constantly trying to do more and thinking that they're not doing enough… it's having a negative impact. You're demoting your social rank, your body internalizes that as a chronic inflammatory stress response.”
— Dr. Tommy Wood (20:45)

6. Allostatic Load — Invisible Burden of Stress

• Allostatic load = cumulative “wear and tear” from chronic stress and lifestyle (high blood pressure, blood sugar, inflammation) (23:34–29:00).
• It’s often “invisible”—not obvious unless you measure it (29:52).
• Vitamin D often lower in high stress, but unclear if cause or effect (30:20).

7. Retirement & Brain Decline: Use It or Lose It

• Retiring, especially “early retirement,” is “when risk of decline starts to increase” (31:48).
• Mechanism: Removal of cognitive and social stimuli from work accelerates loss of cognitive function (32:10).
• Continuing to “learn new things, interact with the world, engage our brains” is protective—work complexity, lifelong education, challenging hobbies are crucial (34:55–36:16).
• “Cognitive function, on average, peaks around the time that we leave formal education… our brains don’t necessarily get worse, just how they work kind of shifts” (32:55).

Notable Quote

“If you get into your 30s or later and try to learn a language, it’s harder… but it’s actually in the sucking that the magic happens. That’s what drives neuroplasticity, is making failures.”
— Dr. Tommy Wood (37:40)

8. Exercise — Especially Resistance Training — Builds Brain Health

• Resistance training especially benefits “white matter,” critical for fast communication between brain regions and for executive function (38:56–41:00).
• “Resistance training seems to preferentially benefit the structure and function of the white matter, and as a result, seems to be particularly beneficial for things like executive function and decision making.” (40:37)
• IGF-1 (promoted by resistance exercise) key for white matter resilience.
• Improvements measured by MRI; correlations with lower dementia risk. Just two days/week is enough for brain effects (45:30).

9. Nutrition for Cognitive Longevity — It’s the Pattern, Not One Food

• “Plants and vegetables are more beneficial for the brain as it relates to cognitive decline,” but moderate, unprocessed red meat can be fine, especially for essential nutrients (46:20–47:45).
• Mediterranean and similar patterns (nutrient-dense, minimally processed) offer best evidence (47:50).
• Focus on “nutrient status” over demonizing specific foods; context matters.

“It’s not these individual foods which we get so focused on. It’s your overall dietary pattern.”
— Dr. Tommy Wood (48:30)

10. Personal Biomarkers & Nuance Over Absolutes

• Guidance must be tailored to the individual’s biomarkers and context—what’s “bad” for one (e.g., red meat, LDL) may be neutral in another’s physiology (49:54–52:00).
• Many people can “eat huge amounts of very fatty meat and it has no effect on their lipid markers whatsoever.”

11. The 3S Model for Brain Health (from The Stimulated Mind)

• Stimulus: Regular, meaningful cognitive/social/physical mental challenges—must be “mentally hard, where you are making mistakes and learning” (54:28).
• Supply: Cardiovascular health, metabolic health, nutrients (omega-3s, B vitamins, vitamin D, iron, glucose).
• Support: Sleep, recovery, stress avoidance—all crucial for adaptation.
• “When you change one thing, you change everything”—progress in one area improves the whole system (57:23).

“It's not this long list of things you need to do—it's identifying some individual things where you can start to make a change. And then when you make a change, the whole network shifts in your favor.”
— Dr. Tommy Wood (57:32)

Notable Quotes & Memorable Moments

• “Cognitive decline is not destiny—it's driven by what you do.” (01:32)
• “How the brain looks under the microscope tells us almost nothing about how it functioned in real life.” (04:42)
• “Being kind to yourself is actually protective for your brain—thinking you’re not doing enough is harmful.” (17:55, 20:45)
• “It's actually in the sucking that the magic happens… making mistakes drives neuroplasticity.” (37:40)
• “Just two days a week of resistance training is enough to yield brain benefits.” (45:30)
• "Don't focus on 40 things. Focus on the 3S's: Stimulus, Supply, Support." (52:35, 54:28)

Timestamps for Key Segments

• Brain As Formula 1 vs. Truck & Agency Over Decline: 00:00–04:26
• Supplements, Nootropics, and Stimulants: 08:38–11:34
• Elite Athlete Brains & Neuroplasticity: 11:34–15:00
• Dementia, Definition, and Preventability: 16:05–17:55
• The Science of Self-Kindness & Social Stress: 17:55–22:59
• Allostatic Load, Invisible Stress, & Vitamin D: 23:17–31:05
• Retirement, Learning, and Cognitive Resilience: 31:06–38:22
• Resistance Training & Brain Structure: 38:22–45:30
• Nutrition, Biomarkers, and Dietary Nuance: 45:30–52:04
• 3S Model for Brain Health: 52:04–57:43

Final Takeaways

• Cognitive decline is not inevitable; lifestyle has immense power.
• Don’t chase expensive supplements—prioritize movement, challenging your mind, whole foods, restful sleep, and self-compassion.
• Be wary of comparing yourself to others or online “optimization” culture; it may harm more than help your brain.
• Consistent application of the 3S’s (Stimulus, Supply, Support) is manageable, evidence-based, and life-enhancing.

For more depth, find Dr. Tommy Wood’s book The Stimulated Mind and follow Louisa Nicola for ongoing brain health content.