The New Science Of Preventing Dementia: Protect Your Brain, Boost Your Focus, Resist Cognitive Decline with Dr Tommy Wood #638

What It Covers

Dr. Tommy Wood, neuroscientist and Formula One performance coach, presents evidence that 45–70% of dementia cases are preventable using his three-part framework: Stimulate, Supply, and Support. The conversation covers how mindset, cognitive stimulus, metabolic health, sleep, social connection, and structured daily routines collectively determine long-term brain function and dementia risk at any age.

Key Questions Answered

• •Dementia Preventability Data: Two major studies establish that 45–70% of dementia cases are potentially preventable. The 2024 Lancet Commission report attributes 45% to modifiable risk factors including hearing loss, smoking, obesity, and head trauma. A UK Biobank study pushes that figure to 70% when additional factors like poor sleep and insufficient late-life cognitive stimulation are included. These numbers represent population-level probabilities, not individual guarantees, but they reframe dementia as a condition to actively reduce risk for rather than passively accept.
• •Stereotype Embodiment and Cognitive Decline: Expecting cognitive decline accelerates it through a self-fulfilling mechanism called stereotype embodiment theory. When people believe decline is inevitable, they stop engaging in the activities that prevent it — learning new skills, physical challenge, social interaction. The Seattle Longitudinal Study, tracking participants every seven years across multiple decades, found that more than 50% of people maintained cognitive function into their seventies and eighties, directly contradicting the assumption that decline is the norm after one's thirties.
• •The Stimulate-Supply-Support Framework: Brain health operates through three interconnected inputs. Stimulate means engaging in complex, multisensory skill-building — music, languages, tango, visual art, and even complex video games all strengthen the same brain networks, specifically the frontoparietal network governing attention and memory. Supply covers blood flow and nutrients: vitamin D, omega-3 fatty acids, B vitamins (B12, folate, B6, riboflavin), magnesium, zinc, and antioxidant polyphenols from berries and coloured vegetables. Support encompasses sleep, hormonal health, BDNF from exercise, and avoiding smoking, excess alcohol, and chronic stress.
• •Social Media, Perceived Social Rank, and Brain Inflammation: Research by George Slavich and Steve Cole at UCLA links perceived social rank to measurable immune system changes. Constant exposure to curated content on social media triggers internal social demotion — users unconsciously rank themselves lower than peers — which produces physiological stress responses identical to social isolation. This shifts immune function toward chronic low-grade inflammation, a recognised risk factor for heart disease and dementia. Quitting or significantly reducing social media use shows well-being improvements after approximately four weeks.
• •Exercise Timing Around Learning: Physical movement before or after a focused learning session improves memory consolidation through two mechanisms: increased cerebral blood flow and elevated neurotransmitters including dopamine and norepinephrine that enhance attention and encoding. Prolonged sitting reduces brain blood flow and lowers mood, which compounds cognitive fatigue. Even brief movement breaks — five minutes of walking — partially restore blood flow and cognitive readiness, making structured exercise snacks around study or deep work sessions a practical tool for students and knowledge workers.
• •Cognitive Gears and the Tired-But-Wired Cycle: The brain operates in three modes: high gear (deep focused work), middle gear (meetings, emails, multitasking), and low gear (rest, free association). Most people spend entire workdays in middle gear — the equivalent of jogging continuously — which creates chronic low-level stress without producing the satisfaction of completed focused work. This unresolved stress drives evening screen use and alcohol consumption, which impairs sleep and restarts the cycle. Structuring even 30 minutes of uninterrupted high-gear work daily, timed to personal peak alertness, breaks this pattern.
• •Women's Brain Health and Cognitive Stimulus: Approximately two-thirds of Alzheimer's disease burden falls on women. Historical data from the Seattle Longitudinal Study identified low environmental complexity — measured by occupational and hobby-related cognitive demand — as a primary predictor of cognitive decline, with the affected group being overwhelmingly women in traditional homemaker roles. As women's access to education and complex employment expanded from the 1970s onward, age-specific dementia incidence decreased. This positions equitable access to cognitively stimulating environments, not hormonal changes alone, as a central lever in women's long-term brain health.