美国国家公共电台 NPR Eating Leafy Greens Each Day Tied to Sharper Memory, Slower Decline（在线收听）

RACHEL MARTIN, HOST:

To age well, it is said, we must eat well. But exactly what kinds of foods may be most beneficial for the aging brain? NPR's Allison Aubrey looks at the latest evidence coming from a study of healthy seniors who live in retirement communities in suburban Chicago.

ALLISON AUBREY, BYLINE: Candy Bishop is not one to let age get in her way. When I reached her the other morning at 8 a.m., she was already dressed for an exercise class. And when I asked her if she still feels mentally sharp...

CANDACE BISHOP: Oh, God, yes. Oh, absolutely. I'm still pretty damn bright, yes.

AUBREY: Bishop is one of about a thousand participants in Rush University's Memory and Aging Project. Their average age is 81. Each year, they take a battery of tests to analyze memory. Researchers also track their exercise and diets. Candy Bishop says, over her lifetime, she's not been a purist when it comes to eating well, but one habit she has been absolutely committed to is this.

BISHOP: My goal is, every day, to have a big salad. Instead of buying a lot of different lettuces, I'll get those bags of darker, leafy salad mixes.

AUBREY: With greens such as spinach and kale. She also tosses in other stuff she likes.

BISHOP: Carrots I like a lot - raw carrots - and radishes are good.

AUBREY: Turns out, these daily salads may help explain Candy's healthy aging. The latest data from the Rush study published in the journal Neurology shows that the participants who eat the most leafy greens - about a serving and a half per day - have had a much slower rate of cognitive decline compared to those who eat little or no greens. Over about a five-year period, the heavy greens eaters declined at about half the rate. Here's study author Martha Clare Morris.

MARTHA CLARE MORRIS: Our study does suggest that leafy greens have a number of nutrients that play different protective roles in the brain.

AUBREY: For instance, leafy greens contain plenty of vitamin E, lutein and folate. Morris says more research is needed to understand how exactly they influence the brain, but scientists do know that too little of these nutrients can be problematic.

MORRIS: If you have insufficient levels of folate in your diet, you can have higher levels of homocysteine.

AUBREY: Which can set the stage for inflammation and a buildup of plaque inside your arteries.

MORRIS: So when you eat leafy greens, you're eating a lot of different nutrients, and together, they can have a powerful impact.

AUBREY: Candy Bishop says it's good to know that greens and other food she likes, such as fish, seem to be good for her brain. But she says she thinks a lot of how you age is in your genes.

BISHOP: I don't feel that I have any secrets. I just think I'm damn lucky, frankly.

AUBREY: Of course, many factors influence the aging process, and this study does not prove that eating greens will fend off memory decline. What it does do is add to the evidence that diet matters. As for Candy Bishop, despite feeling sharp, she says she does notice little slips.

BISHOP: Who was that? What was this guy's name?

AUBREY: But she chalks that up to a normal part of aging.

BISHOP: As time goes by, you know, you're not a - (singing) you're not a kid anymore - if you remember that old song.

And the answer is, no, I'm not a kid anymore.

AUBREY: But she says she will keep eating her greens. Allison Aubrey, NPR News.