How to Avoid Cognitive Decline & Dementia (starting in your 40s) | Dr. Tommy Wood

Neuroscientist Tommy Wood explains that age-related cognitive decline is driven more by lifestyle choices than by age or genetics. He introduces his 3S model — stimulus, supply, and support — as the key framework for maintaining brain health, and warns that retirement is the single biggest danger zone because it removes daily cognitive challenge, putting highly educated people at particular risk. The conversation covers the difference between retrieval and encoding problems, why age-specific dementia rates have actually been falling, and the two numbers to check at your doctor's office in your 40s or 50s.