F iber gets a lot of well-deserved credit for keeping the digestive system in good working order—but it does plenty more. In fact, it’s a major player in so many of your body’s systems that getting enough can actually help keep you youthful.

For example, older people who ate fiber-rich diets were 80 percent more likely to live longer and stay healthier than those who didn’t, according to a recent study in the Journals of Gerontology.

The trouble is, few Americans consume the amount they should. For people age 51 and older, government guidelines recommend at least 28 grams per day for men and 22 grams for women. But the Department of Agriculture says adults in this age group average just about 16 grams per day.