The advice from Alzheimer's Research UK boils down to one rule of thumb the charity says all the best evidence supports: what is good for your heart is good for your brain. Physical activity helps the heart pump blood around the body, delivering oxygen and nutrients to the brain, and research suggests people who exercise regularly tend to have healthier brains with less damage to the small blood vessels. Diet matters on the same terms - too much saturated fat and sugar has been linked to raised risk of both heart disease and dementia.
Two studies illustrate the point. In a US study of more than 2,000 volunteers over 65, participants reported their diet, how often they did mentally stimulating activities, and how much physical activity they did. Those who ate well, exercised and challenged their brains lived longer, and among those who did develop Alzheimer's, it tended to arrive at an older age. A Chinese study that followed 500,000 people for 10 years found that walking for pleasure, doing DIY and catching up on housework were all associated with a lower risk of dementia - no gym membership or athletic ability required.
Timing appears to matter as much as the activities themselves. Alzheimer's Research UK points to evidence that steps taken in the 30s, 40s and 50s are especially important, because the brain changes behind diseases like Alzheimer's can begin decades before memory and thinking problems appear. The Insight 46 study found that blood pressure changes in the 40s and 50s were linked to more signs of blood vessel damage in the brain by the 70s, which is why midlife blood pressure has become such a focus for researchers.
The practical message from the charity is about sustainability rather than intensity: dancing in the kitchen or walking instead of catching the bus counts, and finding healthier versions of recipes you already like is easier to stick with than an overhaul. These studies show associations rather than proof that any single habit prevents dementia, but the consistency across large populations is what makes cardiovascular health one of the more solid threads in dementia risk research.