How Fitness Protects Aging Brains by Joseph Mercola Recently by Joseph Mercola: Toxicology Expert Explains Why Aspartame Is So Dangerous to Your Health Story at-a-glance A new study finds physical exercise, more than mental exercise, protects your brain against age-related changes; people who engaged in the most physical exercise showed the least brain shrinkage Exercise, diet, and stress management are three primary factors that play key roles in maintaining sharp mental function as you age Exercise promotes brain cell regeneration and production of key brain chemicals and growth factors such as BDNF, which is important in maintaining memory, skilled task performance, and overall cognitive function Your dietary choices are another important factor in brain health; your brain is comprised mostly of fat so requires abundant dietary fats in order to repair and regenerate; one of the most potent and bioavailable sources of animal-based omega-3 fat for your brain is krill oil Some of the best brain foods are fresh vegetables, berries, organic eggs from pastured hens, raw milk and meat products from pastured animals, nuts, avocados, coconut oil and olive oil