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

When it comes to our bodies we all know that the good fats are best.

But what about our brains?

The results published online May 18 in the journal Annals of Neurology has shown that the cognitive function of older women who ate monounsaturated fats was better than those who ate saturated and trans fats.

Compared with those women who ate the lowest amounts of saturated fats, women in the highest saturated-fat category showed worse overall cognition and memory over the four years of testing. Women who ate the most mono-unsaturated fats, which can be found in olive oil, had better patterns of cognitive scores over time. Trans fats weren’t associated with changes in cognition over time, the researchers reported.

With diseases such as Alzheimer’s and dementia on the rise, the benefits could be greater that simply better memories and improved cognition.

Preventive measures to stem the increase of debilitating brain illness could benefit millions.

Studies find that even mild activity is better than no activity when it comes to preventing Alzheimer’s.

For those whom may be too frail for swimming or gym activities it appears as though light housework and gardening can be effective ways to keep active and avoid the disease.

The study, which was published this week in the journal Neurology, included 716 dementia-free men and women in their 70s and 80s. Compared with the most active people, those with the lowest levels of overall physical activity had more than double the risk of going on to develop Alzheimer’s. Greater physical activity was also associated with a slower rate of aging-related memory and cognitive decline.

“This suggests that people in their 80s who can’t participate in formal exercise still get a benefit by leading a more active lifestyle,” says lead author Dr. Aron S. Buchman, associate professor of neurological sciences at Rush University Medical Center, in Chicago. “You don’t have to get a membership in the local YMCA. If you walk up some more steps, stand up and do the dishes more, you stand to benefit because it’s incremental and adds up over the course of a full day.”

The key is to keep moving!

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.