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Yet more evidence points to the importance of exercise, especially walking, to prevent Alzheimer’s and dementia.

Here are a few Alzheimer’s facts that might keep you motivated to exercise and stay fit.

An estimated 5.3 million Americans of all ages have Alzheimer’s disease (2010).

This figure includes 5.1 million people aged 65and older and 200,000 individuals under age 65 who have younger-onset Alzheimer’s.

One out of eight people age 65 and older (13 percent) has Alzheimer’s disease.

Women, who on average live longer than men, are more likely than men to have Alzheimer’s disease.

Alzheimer’s is the most frequent cause of dementia, accounting for 70 percent of all cases of dementia in Americans aged 71 and older.

By 2030, all baby boomers will be at least 65 years old.

That year, the number of people aged 65 and older with Alzheimer’s is expected to reach 7.7 million, more than a 50 percent increase from the 5.1 million age 65 order older currently (2009) affected.

Learn more about the benefits of exercise for Alzheimer’s.