Fiber Facts

A healthy diet includes plenty of dietary fiber, but you may be wondering just what that means. Here are the facts you need to know about fiber-rich foods and how they can benefit you, from lowering your cholesterol and blood glucose, to helping you lose weight.

What Is Dietary Fiber?
Dietary fiber (also called fiber, roughage or bulk) is present in all plants eaten for food, including fruits, vegetables, grains and legumes. Fiber is the term for a special type of carbohydrate from plants your body cannot digest. In other words, when you eat foods with fiber, the fiber passes through the bowels (intestinal track) without being changed into energy for your body. This is why adding fiber to your diet adds bulk without adding calories. Fiber also helps to eliminate waste from the body. Research shows people who eat a high-fiber
diet with plenty of fruits, vegetables and grains are less likely to develop certain types of cancer.

Fiber comes in two forms:
1. Soluble fiber is fiber that dissolves in water. Soluble fiber has a beneficial effect on the body, such as lowering blood cholesterol and blood glucose levels. It helps the body get rid of cholesterol. It can also slow the release of glucose into your blood after you eat a meal. According to the American Heart Association, foods high in soluble fiber include oat bran, oatmeal, beans, peas, rice bran, barley, citrus fruits, strawberries and apple pulp.

2. Insoluble fiber is fiber that does not dissolve in water. It helps prevent constipation. It bulks up waste and helps move it through the bowel. Insoluble fiber has been associated with decreased risk for heart disease and slower progression in high-risk individuals. Foods high in insoluble fiber include whole-wheat breads, wheat cereals, wheat bran, cabbage, beets, carrots, brussels sprouts, turnips, cauliflower and apple skin. Some foods, like oats and apples, have both insoluble and soluble fiber.

How Much Fiber Should You Eat?
According to the American Heart Association, you should eat at least 25–30 grams of dietary fiber from foods (not supplements) — in both soluble and insoluble forms — every day. Current dietary fiber intakes among adults in the United States average about 15 g, or about half the recommended amount.

Similar advice comes from the National Academy of Sciences' Institute of Medicine, which provides science-based advice on medicine and health. It makes the following daily recommendations on fiber
intake for adults:

Fiber Can Help You Manage Chronic Illness
Fiber plays an important role in preventing and managing chronic diseases, including diabetes, heart disease, hypertension and obesity.

Diabetes: Soluble fiber slows the release of glucose into your blood. Slowing the release of glucose helps keep your blood sugar level from rising too quickly after a meal. Eating enough fiber can improve blood glucose levels and reduce the amount of insulin you need to take to manage your disease. It can also reduce your risk of developing type 2.

Heart disease: A major risk factor for heart disease is having a high cholesterol level. Eating a fiber-rich diet can help you reduce your cholesterol. Soluble fiber such as oatmeal and oat bran binds with LDL ("bad") cholesterol and moves it out of your body through the bowel movement or stool.

Obesity: High-fiber foods are an important part of any good weightloss program. Because fiber is not absorbed in the body it adds no calories to your diet. But it does help you feel full. Insoluble fiber helps push waste through your intestines so you digest other foods better. High-fiber foods are also an important source
of vitamins and minerals.


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