Peristalsis is the involuntary contraction of smooth gastrointestinal muscles that causes food to move through your digestive tract. Many things can slow peristalsis, including physical inactivity and poor nutrition. If you experience frequent constipation, some dietary changes may be all you need to stimulate peristalsis and get things moving again.
Physiology of Peristalsis
Peristalsis begins when a bolus, or mass of chewed food, is swallowed, triggering a reflex of smooth muscle action. Nerves are stimulated in the digestive tract that cause smooth muscles to contract above and relax below the descending food, pushing it through the system. The bolus moves from the mouth to the esophagus to the stomach, where it mixes with digestive juices and other digestive agents. From there it descends to the small intestine, where it mixes with bile and becomes chyme. In the small intestine, chyme is processed in the duodenum, passed to the jejunum, where carbohydrates and proteins are absorbed, and to the ileum, where iron and other nutrients are absorbed. It then passes to the large intestine, where water is extracted, and out of the body through the rectum.
Factors Influencing Peristalsis
According to the National Digestive Diseases Information Clearinghouse, or NDDIC, constipation is a symptom of slowed peristalsis. The NDDIC lists inadequate dietary fiber and lack of physical activity as two primary causes of constipation. Other causes are dehydration, medications, abuse of laxatives and life changes like pregnancy, travel and aging. As you age, decreased muscle tone and slower nerve impulses combined with medications and decreased physical activity can cause peristalsis to slow, resulting in constipation.
Diet and Peristalsis
Nutrition plays an important role in peristalsis. Dietary fiber found in whole fresh fruits and vegetables and whole grains stimulates peristalsis, flushing out fats and waste. Gas-producing foods like broccoli and cabbage also stimulate peristalsis. Drinking plenty of fluids is important because it keeps stools soft and easy to pass. Yogurt and other probiotic foods contain live bacterial cultures that promote healthy intestinal flora that facilitate digestion. Foods low in fiber, like meats, milk, cheese and refined carbohydrates, pass slowly through your digestive tract and can slow peristalsis. Eat low-fiber foods in moderation, and combine them with high-fiber sources.
Physical Activity and Other Factors
In addition to poor dietary habits, physical inactivity can slow peristaltic action. Engaging in regular daily exercise speeds up your metabolism and stimulates the digestive process. Psychological factors like depression can slow peristalsis, as can a disruption in timing of bowel habits or lack of privacy. Pregnancy, surgery, illness and medications can also reduce peristaltic stimulus.