Fiber. It's one of those words we associate with a healthy diet. But do you have any idea why dietary fiber—those starchy substances found in fruits, vegetables, and grains that can't be digested in the human body—is so good for you?


Fiber as Calorie-Blocker

Adding fiber to the meals you eat may help you get fewer of the calories you gobble down. Since fiber takes up more room in your stomach than other foods, you feel fuller faster—and thus consume less. And according to the USDA, fiber may block some of our body's ability to absorb calories from the foods that we eat, particularly fat and protein. So if we double our fiber intake from a lowly 12 g a day to a very doable (and expert-recommended) 24 g a day, we could lose about 80 calories per day. That adds up to about two thirds of a pound each month—or about eight pounds a year—simply by sneaking in extra fiber.


Fiber as Disease-Fighter

If you look at a box of oatmeal, you'll see that a diet rich in soluble fiber (which is present in healthy amounts in oatmeal and other oat-filled foods) may help reduce your risk of heart disease. In addition, a fiber-rich diet may also help keep your blood sugar within a normal range and play a positive role in the prevention of some forms of cancer.


Fiber as Diet Tool

In a study published recently in the Journal of the American Medical Association, researchers showed that adults (both women and men) who consumed higher amounts of fiber in their diets were able to keep weight off successfully. The researchers noted that people who ate just 24 g of fiber every day showed less weight gain over time compared to their counterparts who ate low-fiber diets. The moral of this story: If you want to keep weight off over time, make sure you keep fiber in your diet.


The Fast Facts on Fiber

Figuring out fiber isn't so difficult. First, you need to know that there are two types: soluble and insoluble. Basically, soluble fiber dissolves in water and insoluble fiber does not. Soluble fiber is found in oat bran, dried peas, and beans, as well as in many fruits and vegetables. Insoluble fiber, which keeps things moving in your gastrointestinal tract and helps ward off constipation, is found in wheat bran, whole-grain breads, cereals, vegetables, and fruit. We need both types in our diets because each has an important role in good health.


Fitting in Fiber

Some easy ways to sneak fiber into your daily eating plan? Eat an apple or pear daily to add at least 3 g of fiber. Swap a baked potato with the skin (4 g) for mashed (1 g), brown rice (2 g) for white (1 g), and bran flakes (5 g) for corn (1 g). And become a whole-grain convert—switch to whole-grain bagels and bread, whole-grain cereal bars, and whole-wheat pasta.