Could eating a salad a day help protect your brain against aging?

(CBS News) - There's even more of a reason to get your daily fix of leafy greens. New research shows that eating a salad a day may help keep your brain healthy.

The study, published in Neurology, the journal of the American Academy of Neurology, found that people who ate at least one serving of green, leafy vegetables per day had a slower rate of decline on tests involving memory and thinking skills than people who never or rarely ate these vegetables.

"Older adults who consumed leafy greens in their diet -- the equivalent of about a cup and a half a day -- they have lower risk of developing memory deficits associated with dementia," study author Sarah Booth, PhD, of the Nutrition Research Center on Aging at Tufts University told CBS News.

The study followed 960 people who did not have dementia, with an average age of 81, for about 5 years.

The participants completed a questionnaire about how often they ate certain foods, including green, leafy vegetables such as cooked spinach, kale, collard greens and raw lettuce salad.

They also had their thinking and memory skills tested yearly during that time.

The research found those who ate the most leafy greens tested the equivalent of 11 years younger on measures of mental function, compared to those who ate the least. Previous studies have found that people who follow the Mediterranean dietor similar MIND or DASH diet plans -- rich in fresh vegetables, fruits, whole grains, and healthy fats -- have a lower risk of developing dementia.

Researchers say it's best to choose greens with dark leaves because the darker the leaves the more nutrients they have.

Booth says while the new study doesn't prove that leafy vegetables slow brain aging, incorporating them in your diet is a good idea.

"There are so many other chronic diseases that the onset and progression is delayed from consuming leafy greens because the leafy greens contain many nutrients," she said.

That's what Pedro Velazquez is trying to do. He goes to the gym regularly then hits the salad bar afterwards. "I used to eat a lot of fried food and Spanish food, now I'm trying to healthy," he told CBS Boston's Dr. Mallika Marshall.

He's eating two to three servings of greens each week now, but says he may start serving up more salad for his body and mind.

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