Constipation: Nutritional Considerations

• Increasing intake of high–fiber foods: The most common cause of constipation is a diet low in fiber. Fiber is found only in plant–derived foods, such as beans, vegetables, fruits, and whole grains. In contrast, animal–derived foods and heavily processed food products do not contain fiber.
  
  Americans eat an average of 5 to 14 grams of fiber daily, far less than individuals residing in less–developed countries. In persons eating more traditional, higher–fiber diets, constipation is rare. Increasing dietary fiber intake has been shown to improve constipation and significantly reduce the need for laxatives, especially in children, the elderly, and postsurgery patients.
  
  Although high–fiber foods should generally be the first choice, some patients may benefit from fiber supplements. Evidence indicates that fiber supplements permit discontinuation of laxatives in about 70 percent of constipated patients. Several types of fiber supplements have been shown to be effective for constipation relief, including psyllium (Metamucil), methylcellulose (Citrucel), and Japanese konjac root (glucomannan).
  
• Increasing fluid intake: Poor fluid intake is commonly associated with constipation, especially in children. In one study, a combination of 25 grams of fiber and 1.5 to 2.0 liters of fluid daily was more effective treatment for constipation than fiber intake alone.
• Avoiding cow’s milk: Many children with chronic constipation have cow’s milk allergy. One study showed that up to two–thirds of constipated children with cow’s milk sensitivity may have improved symptoms when they remove milk from their diets. Further, a controlled clinical trial found that constipation returned within five to 10 days after reintroduction of cow’s milk.
  
  It is important to realize that cow’s milk is not the only source of calcium. If poor calcium intake is a concern, calcium–fortified soymilk, rice milk, or juices may be substituted for cow’s milk.