What is fiber? Why do we need it?
Fiber is found in fruits, vegetables, grains, nuts, seeds, and beans. Unlike sugar and starches, fiber is a carbohydrate that we cannot digest. Adequate fiber intake can help us maintain good health in several ways (Institute of Medicine, 2005).
- Some types of fiber help slow down the body's absorption of glucose (sugar). This can help control of blood glucose.
- Some types of fiber help to reduce blood cholesterol. This can help reduce the risk of heart disease.
- Other types of fiber help keep our bowel function regular.
- Higher fiber foods may help us feel full or satisfied longer after eating. This may help with weight control.
Foods contain different types of fiber. It's important to eat a wide variety of plant foods to get the most health benefits from fiber. Higher intakes of fiber from plant foods are associated with a reduced risk of heart disease, type 2 diabetes, and cancer (Dahl & Stewart, 2015).
What happens if we don't get enough fiber?
Fiber helps to form larger, softer stools that pass with regularity. Without enough fiber, we may suffer from constipation and hemorrhoids. Inadequate fiber intake may also increase your risk of many chronic diseases (Dahl & Stewart, 2015).
How much fiber do we need?
Recommendations for fiber intake are based on studies of the amounts needed to reduce heart disease risk. This level of fiber intake will also help prevent constipation. Table 1 lists the recommended Adequate Intakes (AI) for fiber (Institute of Medicine, 2005).
How can we get enough fiber?
Fruits, vegetables, beans, nuts, seeds, and whole grains provide fiber. Fruits and vegetables with edible skins and seeds are good choices for fiber. Most juices contain almost no fiber, so choose whole fruits and vegetables more often. Make sure that at least half of your daily grain servings are whole grain. Look for products that have a whole grain such as whole wheat, brown rice, or whole rye first on the ingredient list, as these will usually contain the most fiber. Table 2 lists the fiber content of some common foods.
For packaged foods, read the Nutrition Facts Panel and choose foods with more than 2 g of fiber per serving. Some foods, such as bread and baked goods, have added fiber. For more information about foods with added fiber see EDIS publication FS235, Shopping for Health: Foods with Added Fiber (FSHN13-11) at https://edis.ifas.ufl.edu/publication/FS235.
Additional tips for increasing fiber intake:
- Snack on raw vegetables instead of chips or crackers.
- Substitute beans or legumes for meat in soups or chilis.
- Include fresh fruit as a snack or dessert.
What about fiber supplements?
It's best to get fiber from food rather than from supplements. Not only are foods more enjoyable to eat, but they also are packed with nutrients needed for good health, such as vitamins and minerals. Fiber supplements usually don't have these added benefits. If you think you need a fiber supplement, first talk to your healthcare provider.
For more information on fiber supplements, see EDIS publication FS162, Guide to Fiber Supplements (FSHN11-01) at https://edis.ifas.ufl.edu/fs162.
How much fiber is too much?
There is no upper limit for fiber from whole grains, fruits, vegetables, nuts, seeds, and beans (Institute of Medicine, 2005). Very high intakes of fiber may result in gas, bloating, and distention in some people.
Where can I get more information?
The Family and Consumer Sciences (FCS) agent at your local UF/IFAS Extension office may have more written information and classes for you to attend. Also, a registered dietitian/nutritionist (RDN) can provide reliable information to you.
A related EDIS publication—FS161, Shopping for Health: Whole Grains (FSHN10-13)—is available at https://edis.ifas.ufl.edu/fs161.
Dahl, W. J., & Stewart, M. L. (2015). Position of the Academy of Nutrition and Dietetics: Health implications of dietary fiber. J Acad Nutr Diet, 115(11), 1861–1870. doi:10.1016/j.jand.2015.09.003
Institute of Medicine, Food and Nutrition Board. (2005). Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids (macronutrients). Washington, D.C.: National Academy Press.
Fiber contents of selected foods.