The brain is the underrated part
When Marek asked around London for who to see, the answer kept coming back the same: “Go and see Dr Tam.” Dr Tamsin Lewis is a longevity and performance doctor, founder of Wellgevity, and by her own count fourteen years into the field — long before it was fashionable. She hosted the Formentera leg of the quest, and the interview happened on the island.
She has had, in effect, three careers, and they stack. First an elite athlete (her father was a professional sportsman), then a psychiatrist, and now a longevity doctor. She describes herself as kind, inclusive and non-dogmatic — no finger-wagging, no “you must take this at this time” — and credits the psychiatry for teaching her to read the human first and build the health plan on top.
Her central argument is one Marek shares: brain health is the most underrated hallmark of ageing. The whole field looks at cells, muscle, nutrition — and treats the mind last. In psychiatry she noticed the reverse causation everyone misses: many self-destructive behaviours driven by poor mental health have a physical driver. She began blood-testing her psychiatric patients — hormones, vitamins, gut health — and watched their mental health improve as she corrected the biology. That set her on the gut-brain axis for good.
It is not abstract for her. In her final year of medical school a skiing accident put her in a coma for three days with a traumatic brain injury, and conventional medicine offered her only “plaster medicine” — sleeping tablets, antidepressants. She found her way out through nutrition, sport and supplementation, reducing her own brain inflammation — and notes that most of us carry low-level brain inflammation from knocks we never counted, contact sport at school and the rest.
That is the throughline of her practice: the systems are connected, mood drives behaviour drives biology drives mood, and it often doesn’t matter where you start — only that you start somewhere and follow the thread.
