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To get adequate fiber, the U.S. Dietary Guidelines and the Dietary Reference Intakes (DRIs) indicate that people should include a variety of foods rich in fiber in their daily diets. To increase dietary fiber intake, include whole grain breads and cereals in one's diet.

It is important to note that not all wheat products qualify as “whole grain.” The bran and germ is removed from many wheat products, which reduces the fiber content of the food. When purchasing wheat products, look for the term “whole wheat” or “whole grain” high in the list of ingredients to ensure that the product is packed with fiber. Do not be fooled by the label “enriched wheat flour.” This indicates that certain nutrients were added back into the flour during or after processing. However, it does not guarantee that fiber is one of these added nutrients.  

Other good sources of fiber include fresh fruits, vegetables and beans in the diet. Fiber is best obtained from a variety of foods rather than from a supplement.

Helpful tools to increase intake of dietary fiber can be found on food labels. The nutrition facts label and the ingredients list on the label of packaged foods provide information on fiber content.

When increasing dietary fiber content it is important to do so gradually to allow the digestive tract to adjust. Side effects of increasing fiber intake too rapidly include excess gas formation, bloating, abdominal cramps or diarrhea. When increasing dietary fiber intake, it is also important to drink plenty of fluids. Dietary fiber readily absorbs liquid, so people who increase fiber intake without boosting water intake risk depriving their cells of necessary water. Experts recommend that men drink 12 eight-ounce glasses of water or other noncaloric beverages each day, and that women drink at least 9 eight-ounce glasses of water or other noncaloric beverages each day.  

The following are some tips for increasing fiber intake:

• Eat plenty of fruits and vegetables. These foods are naturally high in fiber. Eat fresh fruits and vegetables instead of drinking their juices, which lack fiber-rich skins or membranes. To keep the fiber content of vegetables high, eat them raw or steamed until slightly tender. Leaving the skins on the vegetables also increases fiber. For example, a medium baked potato with the skin provides 5 grams of fiber.
  
  
• Replace refined grains with whole grains. For example, choose brown rice, whole-wheat breads and whole-grain products instead of white rice, bread and pasta.
  
  
• Choose whole grain cereals for breakfast. Instead of sweetened cereals full of added sugars, choose unsweetened whole-grain cereals and add your own dried fruits. Another option is to mix one-quarter cup high-fiber bran cereal with your regular cereal.
  
  
• Add dried fruits, nuts or seeds to plain low fat yogurt, muffins, quick breads, salads, pilafs or other dishes.
  
  
• Beans, lentils and peas are low in fat and an excellent source of fiber, protein, and vitamins and minerals. Keep canned or frozen beans or peas handy to add to soups, stews, salads and rice dishes.
  
  
• Nuts are a good source of fiber and protein, but they are also high in fat. However,  these fats are mostly unsaturated fats that reduce the “bad” low-density lipoprotein (LDL) cholesterol levels.
  
  
• Snack on high-fiber foods. These include fresh and dried fruit, raw vegetables, low-fat popcorn and whole-grain crackers.
  
  
• Sprinkle crushed bran cereal or unprocessed wheat bran on breakfast cereals and baked products such as bread, cakes, casseroles, cookies, meat loaf and muffins.
  
  
• Use whole-grain flour instead of white flour. Because whole-grain flour is heavier than white flour, it may help to add more yeast or baking powder when baking.

Parents are urged to use caution when adding extra fiber to their child’s diet. Excessive amounts of high-fiber foods may cause a child to fill up quickly, reducing appetite and potentially depriving the child of needed nutrients from a well-rounded diet.

Elderly people and those who have had gastrointestinal surgery also are urged to exercise caution when boosting fiber intake. Such populations are more likely to feel the added effects of additional fiber consumption.

Although it is very rare in the typical American diet, people are urged not to eat too much fiber. Excessive amounts of fiber may move food through the digestive tract so quickly that some nutrients will not be absorbed. More than 50 to 60 grams of fiber daily can lower the absorption of vitamins and minerals such as calcium, iron, magnesium and zinc.

Because fiber delays emptying of the stomach, patients with gastroparesis are advised to consult their physician about whether they need to restrict or avoid consumption. Gastroparesis is a condition that causes delayed or incomplete digestion of food.