More than 7 million Americans are living with Alzheimer’s disease, and that number is projected to nearly double by 2051, according to the Alzheimer’s Association.

Older Americans are more fearful of developing this memory-robbing disease than any other condition, including cancer, stroke, and heart attack, according to a recent poll.

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Can this devastating disease be prevented?

“If we define prevention as a cure, the answer is no,” says Dr. Gary Small, brain health expert and chair of psychiatry at the Hackensack University Medical Center in New Jersey. “But a more modest and realistic and achievable goal is to delay symptom onset. And there’s tremendous science now that tells us we can delay the onset of symptoms by many years.”

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Exercise: The #1 Brain Booster

One of the simplest yet most powerful tools for protecting brain health is physical activity, Small tells Newsmax’s "National Report."

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“No. 1 is physical exercise. What’s good for your heart is going to be good for your brain,” he explained. “One study found that just 30 minutes of a daily brisk walk will delay the onset of Alzheimer’s symptoms.”

The benefits extend beyond memory. “When we exercise, we get our heart to pump oxygen and nutrients to the brain. We produce endorphins, which are natural mood lifters. We also produce proteins that help our brain cells connect more efficiently — so we’re thinking faster and thinking better,” says Small, who is also the physician in chief for Behavioral Health Services at Hackensack Meridian Health.

A Practical Path Forward

While Alzheimer’s remains incurable, experts emphasize that small, daily steps can empower people to take control of their cognitive health. “That really empowers people to learn a healthy brain lifestyle, to help them stave off this terrifying disease,” says Small.

His latest book, "The Small Guide to Alzheimer’s Disease," provides additional strategies to maintain mental sharpness and reduce risk.

“Go for a walk. Think about the difference it can make,” emphasizes Small.