Citrus fruits are rich in vitamin C, an antioxidant vitamin that seems to slow the development of cataracts. Bran cereals provide fiber that can rev up your intestinal tract, countering the natural tendency of the contractions that move food through your gut to slow a bit as you grow older (which is why older people are more likely to be constipated).

Getting enough calories to maintain a healthy weight helps protect against wrinkles. And although a diet with adequate amounts of fat doesn’t totally prevent dry skin, it does give you a measure of protection. That’s one reason why virtually all sensible diet gurus, including the American Heart Association and the Dietary Guidelines, recommend some fat or oil every day.

And now for a word about memory. Actually, two words: varied diet. A study of 250 healthy adults, ages 60 to 94, at the University of New Mexico School of Medicine in 1983 showed that the people who ate a wide range of nutritious foods performed best on memory and thinking tests.

According to researcher Philip J. Garry, Ph.D., professor of pathology at New Mexico School of Medicine, overall good food habits seemed to be more important than any one food or vitamin. Maybe people with good memory are just more likely to remember that they need a good diet.

Or maybe it’s really the food. In 1997, another survey, this time at Complutense University (Madrid, Spain), showed that men and women ages 60 to 90 who eat foods rich in vitamin E, vitamin C, folic acid, dietary fiber, and complex carbohydrates do better on cognitive tests.

Is it the antioxidant vitamins? Does a low-fat diet protect the brain? No one knows for sure right now, but it may turn out that sticking with this same-old, same-old low-fat, high-fiber diet as you grow older may help you to remember to stick to the same-old low-fat, high-fiber diet — for years and years and years.