"Juice may keep us from losing our minds," says Liz Applegate, Ph.D., nutritionist to Olympians and professional athletes. New research from Vanderbilt University reveals that people who drink at least three glasses of juice a week are 76 percent less likely to develop Alzheimer's disease. Why juice? Polyphenols – plant chemicals in the skins of fruits and vegetables – seem to shield brain cells from age-related decay. To keep your wits intact, Applegate recommends this ultimate daily tonic: a half-cup each of apple, pomegranate and cranberry juice.