Among the many fears about aging, few are as deep as the fear of dementia. Most of us grew up believing memory loss was inevitable, something we couldn’t prevent or delay.
But science is telling a different story. In recent years, research has revealed that how we live has a powerful influence on how our brains age. Regular exercise, healthy eating, quality sleep, and social engagement all play a role in protecting memory and slowing decline.
“Studies show that even moderate exercise can increase the size of the memory center of the brain, the hippocampus,” says Dr. Jonathan Graff-Radford, neurologist and co-author of Mayo Clinic on Alzheimer’s Disease and Other Dementias. “That means you’re not just maintaining; you’re actually helping your brain grow and become more resilient.”
Alzheimer’s disease begins long before symptoms appear, sometimes 15 to 20 years earlier. “By the time someone notices changes, there’s already a lot happening,” Graff-Radford explains. “That’s why prevention and lifestyle are so important.”
Angela Lunde, who co-authored the book with Graff-Radford, emphasizes that prevention is not about fear, but empowerment. She often reminds readers and caregivers that lifestyle choices — daily movement, social connection, and mental stimulation — are among the most meaningful forms of medicine we have.
Doctors are also making progress in early detection, with blood tests now able to identify Alzheimer’s-related proteins with more than 90% accuracy. When the disease is caught early, new medications can help slow its progression. Even more encouraging, large studies suggest that up to 40% of dementia cases could be prevented through lifestyle changes such as regular exercise, maintaining healthy blood pressure, and treating hearing loss.
How Exercise Helps
Movement is one of the most effective tools for keeping the brain sharp. Aerobic exercise improves circulation, delivering oxygen and nutrients that support brain function. Strength training helps control blood sugar and reduces inflammation, both linked to cognitive health.
“What’s good for the heart is good for the brain,” Graff-Radford says. “That means regular exercise, healthy eating, quality sleep, and staying socially and mentally active all work together to lower risk.”
Even moderate activity makes a difference. Brisk walking, swimming, dancing, or lifting weights two or three times a week can help strengthen both body and mind. Activities that combine movement and focus — like yoga, tai chi, or pickleball — challenge coordination and attention in ways that promote brain resilience.
Hope, Not Helplessness
Lunde often writes that living well with brain health in mind is about optimism and intention, not perfection. It’s never too late to start, and small steps can make a lasting difference.
There’s still no certain prevention or cure for Alzheimer’s, but the story has shifted from helplessness to hope. Exercise won’t guarantee a disease-free future, but it stacks the odds in your favor — and it makes every part of life better along the way.
Staying active today isn’t just about building strength. It’s about preserving memories, independence, and the life you love.
Holly Kouvo is a personal trainer, functional aging specialist, senior fitness specialist, brain health trainer, writer, and speaker.