Certain nutrients, too, are thought to be protective. The antioxidants in fruits and vegetables have been linked to improved cognitive function; berries, for instance, seem especially beneficial in keeping brains spry. "Old neurons, like a lot of old married couples, don't talk to each other anymore," says James Joseph, director of the neuroscience lab at the USDA Human Nutrition Research Center on Aging at Tufts University. "We have found that the berry fruits improve neuronal communication." In November, Harvard researchers announced that men who took a beta carotene supplement for 18 years had slightly better cognitive function than those who didn't—their memory scores matched those of people about one year younger. However, men who took supplements for only one year showed no improvement, and several other studies have found no link between antioxidants and mental performance. The Alzheimer's Association recommends a diet high in dark-colored veggies, like kale, spinach, beets, and eggplant; colorful fruits like berries, raisins, prunes, oranges, and red grapes; plus fish like salmon or trout high in heart-healthful omega-3 fatty acids.
Making connections. It has been more than two decades since Bill Harves, 90, quit singing in his church choir. Four years ago, he joined the professionally led chorale that rehearses once a week at his Bailey's Crossroads, Va., continuing care retirement community. The chorale gives several concerts a year, including one at Washington, D.C.'s Kennedy Center. He's gained in breathing technique, enunciation, and music reading skills. "There's no doubt I've improved as a singer," he says.
Besides having fun, Harves, who also serves as chairman of his community's computer club and is active on a residents' committee, is very likely protecting his cognitive function. In a study of more than 2,800 people ages 65 or older, Harvard researchers found that those with at least five social ties—church groups, social groups, regular visits, or phone calls with family and friends—were less likely to suffer cognitive decline than those with no social ties.
"The working hypothesis is that it has something to do with stress management," says Marilyn Albert, a neuroscientist at Johns Hopkins and codirector of the Alzheimer's research center there. In animal studies, a prolonged elevation in stress hormones damages the hippocampus. Social engagement appears to boost people's sense of control, which affects their stress level. Creative arts seem to be a highly promising way to increase social engagement. George Washington University's Cohen has found that elderly people who joined choirs also stepped up their other activities during a 12-month period, while a nonsinging control group dropped out of some activities. The singers also reported fewer health problems, while the control group reported an increase.
All the new research has senior programs rethinking their offerings. In Chicago, for example, Mather LifeWays, a not-for-profit that promotes healthful aging, has opened three neighborhood cafes that serve coffee and sandwiches to people of all ages and offer fitness classes, computer courses, lifelong-learning opportunities, and volunteer activities for older adults. "I've met lots of friends here," says Jill Wonsil, 66, who drops in at the cafe near her home several times a week to socialize, check E-mail, and take exercise and other classes. If living life to the fullest is the best way to stay sharp, it's not such a tough prescription to swallow.