Most Americans say lifestyle behaviors are important for brain health. But less than half connect those behaviors to actually lowering their risk of Alzheimer’s disease.
Here’s where things stand. An estimated 7.4 million Americans age 65 and older are living with Alzheimer’s disease today, along with about 750,000 Canadians. The numbers are expected to rise. The personal stakes are just as striking: at age 45, the lifetime risk is 1 in 5 for women and 1 in 10 for men, according to the Alzheimer’s Association.
Those numbers are sobering. But they’re not the whole story.
Much of this is Preventable
The Alzheimer’s Association reports that half of the world’s dementia cases could be attributed to modifiable risk factors. A 2024 report from the Lancet Commission went even further, identifying 14 modifiable risk factors that, if addressed through lifestyle changes, could reduce the number of dementia cases by 45%.
Read that again. Nearly half of all dementia cases.
“Everyday actions. Lifelong impact,” the organization says.
Nothing is a vaccine, sadly. But the Alzheimer’s Association points to 10 key factors, including physical activity, managing blood pressure and blood sugar, and nutrition. These are areas where consistent exercise and healthy habits make a measurable difference. Physical inactivity sits near the top of nearly every risk factor list, and it’s one of the most addressable.
A 2025 study published in Nature Medicine underscored why. In cognitively normal older adults at risk for Alzheimer’s, physical inactivity was associated with faster tau protein buildup and cognitive decline — tau being one of the hallmark proteins involved in Alzheimer’s progression. Movement, the researchers found, helped slow that process.
Exercise is the Lever You Can Pull Today
This is where strength training enters the picture. A 2025 study followed older adults already experiencing mild cognitive impairment — measurable memory loss and one of the strongest risk factors for dementia. Those who did twice-weekly weight training for six months showed improvements in verbal memory and in the health of brain regions linked to Alzheimer’s. The group that didn’t train showed those regions getting worse.
“Weight training is a strong ally against dementia,” said lead researcher Dr. Isadora Ribeiro, “even for people who are already at high risk of developing it.”
The research is consistent and growing. Exercise strengthens the hippocampus and prefrontal cortex, two primary targets of Alzheimer’s disease. It improves blood flow to the brain, reduces inflammation, and triggers proteins that help brain cells survive and grow.
None of this requires becoming an athlete. Two to three sessions a week, working major muscle groups, is what the research supports.
The choices you make — the workouts you do, the habits you build — are not just about how you look or feel. They’re about who you’ll still be, decades from now.
To learn more about Alzheimer’s Awareness Month, visit the Alzheimer’s Association here.
Holly Kouvo is a personal trainer, functional aging specialist, senior fitness specialist, brain health trainer, writer, and speaker.