What Are the Effects of Soy Milk on Constipation?

Soy is a plant in the pea family and has been used for thousands of years. The seeds of the plant, or soybeans, are high in protein and contain an estrogen-like hormone, according to the National Center for Complementary and Alternative Medicine. Soy is available as an ingredient in some foods as well as a dietary supplement. Soybeans can be used in cooking. Soy may also provide some health benefits, including possible relief from constipation.

Relief of Constipation Due to Food Allergy

The website SoyNutrition.com states that when children who are experiencing stomach upset due to a food allergy to cow's milk and milk products are given soy milk as a substitute, they may experience fewer symptoms of constipation. Soy milk is therefore a good alternative to cow's milk in instances when an allergy to cow's milk is causing constipation, but it should be noted that soy itself does not resolve the constipation. Researchers from the University of Newcastle support the theory that soy milk may be a good substitute, stating that 100 percent of children experiencing chronic constipation as a result of cow's milk experienced relief from the constipation when soy milk was substituted for the cow's milk during a scientific study.

Increased Moisture Content of Stool

According to the National Library of Medicine, some scientific research supports the theory that soy in the form of soy polysaccharide (soy fiber) can increase the moisture content in stools for those on low-fiber diets, which may help alleviate constipation.

Constipation as a Side Effect

Use of soy in large quantities may affect hormone levels, so moderation is urged by the National Center for Complementary and Alternative Medicine. In addition, soy may cause stomach upset, including nausea, vomiting and/or constipation in some people. If these symptoms occur after ingesting soy, discontinue use and contact a physician. Some infants consuming soy formula may be more likely to experience constipation as well. If this occurs, contact your doctor.