It certainly isn't dinnertime conversation, although it has everything to do with eating. In fact, it's something that's rarely talked about, even with the family physician, despite the fact that it affects a majority of Americans. "It" refers to bowel health, and nothing is more fundamental to our well-being. Yet people usually shy away from discussing the particulars of their colon.

Put simply, if your gastrointestinal system isn't working properly, your immunity will be compromised. When correctly functioning, the intestine is where nutrients from food are absorbed and where waste is collected for excretion. When there's a problem, toxins are released into the body—toxins that damage tissue and inhibit the function of white blood cells, which fight disease. Furthermore, nutrient absorption can suffer. The overall result is a weakened immune system, and increasing susceptibility to a variety of health problems and diseases. So, while irregular stools may just seem like an inconvenience, they can actually signify bigger problems.

About average

So what is a "normal" bowel movement? "Basically, you should have a soft, well-formed stool that exits without much straining," says Stephen Holt, MD, author of Natural Ways to Digestive Health (M. Evans and Co. Inc., 2000). Normal bowel excretion ranges from three times a day to three times a week, he says. Stools that appear as small pellets usually mean there's not enough fiber in the diet; this can be remedied by adding more vegetables and whole grains to meals. Stools that are bloody, have large amounts of mucus, or are ribbonlike could be a sign of a serious problem.

If you experience these symptoms chronically, or if changes in your bowel habits last longer than a week, you should see a doctor. These symptoms could be connected with inflammatory bowel disease (Crohn's disease or ulcerative colitis), diverticulosis or Celiac disease (see "Is It Something More Serious?"). Chances are, however, your digestive quirks are related to excessive flatulence, irritable bowel syndrome or stress-related upset.

Down wind

Some people think that belching or flatulence is a sign of something amiss, but in fact it's normal to pass gas a dozen or more times a day. Gas is primarily made up of mostly odorless vapors—carbon dioxide, oxygen, nitrogen, hydrogen and sometimes methane—and is produced from swallowing air and by undigested foods.

When we eat or drink, we swallow small amounts of air, which is usually released in a burp. The air that doesn't leave the body that way works its way down to the large intestine and is then released. The other cause of gas is undigested food in the small intestine. Certain carbohydrates (sugar, starches and fiber) don't get processed due to a shortage or absence of enzymes—proteinlike substances that help facilitate digestion. This undigested food passes to the large intestine, where bacteria breaks it down, producing gas.

Although gas is perfectly natural, it can be uncomfortable and embarrassing. How can you keep it to a minimum? Take smaller bites and eat with your mouth closed to limit excessive air intake. Also, avoid carbonated beverages and foods such as ice cream, soufflés, and light breads, which all contain inordinate amounts of air. You may also have food allergies you're unaware of or just react to certain foods, so monitor what you eat.

Consult a doctor about excessive gas if it interferes with your ability to live a normal life, if you find that you're often bloated, or if you have severe or prolonged pain. You may be suffering from more than gas.

Understanding IBS

It's estimated that 35 million Americans have irritable bowel syndrome (IBS) and, according to the Mayo Clinic, IBS ranks second only to the common cold as a cause of lost work time. Yet many people don't know about IBS; it isn't exactly the subject of water-cooler conversation. The most common symptoms of IBS include gas, abdominal pain or cramping, a bloated feeling, mucus in the stool, and periods of diarrhea and/or constipation.

While the cause of IBS remains a mystery, the most likely culprits seem to be diet and stress. According to the Mayo Clinic Web site, "Some researchers think IBS is caused by changes in the nerves that control sensation or muscle contractions in the bowel. Others believe the central nervous system may affect the colon. And because women are two to three times more likely than men to have IBS, researchers believe that hormonal changes also play a role."

Fortunately, in many cases, IBS can be controlled through diet and lifestyle. "A big part of treating and managing IBS involves what you eat, how much you eat, and where you eat," says Elaine Magee, MPH, RD, author of Tell Me What to Eat if I Have Irritable Bowel Syndrome (Career Press, 2000). Magee suggests keeping an "FFS Diary"—Food, Feelings and Symptoms—to see if there's a pattern with diet, stress and IBS symptoms. The diary can be a simple log of what you eat and drink, your feelings and your physical reactions. "It totally depends on the person. There is a huge range in IBS symptom severity," Magee says. "Many can control their symptoms with dietary changes and managing their stress."

Feelings and guts

What is the link between gut health and stress? "The gastrointestinal tract is a huge body of nervous tissue," says Holt. The enteric nervous system, as it is called, lines the esophagus, stomach, small intestine, and colon. Scientists consider it a single entity and even refer to it as the body's "second brain." It makes sense then that emotions play a huge role in bowel health. "Mind-body medicine is probably the most important, underexplored option to explain the cause and manage the expressions of functional gut disease," says Holt.

Scientists aren't exactly sure how stress and emotions affect digestion. Still, there are several techniques that may help. Ayurvedic medicine and Traditional Chinese Medicine have entire systems connecting the gut and the emotions. In addition, biofeedback, hypnosis, counseling, meditation, and yoga have all been said to relieve symptoms.

Supplemental healing

Popping a pill for your bowel troubles may be more convenient than taking a yoga class, but think twice. While antacids do neutralize stomach acid, they don't treat the underlying imbalance. However, there is convincing evidence that some natural substances can help normalize digestion.

A cup of peppermint (Mentha piperita) tea for an upset stomach isn't just an old folk remedy. Peppermint oil contains menthol, which has an antispasmodic effect on the muscles of the digestive tract and helps dispel gas. Several studies have investigated the effects of peppermint on digestion. In one recent study of 110 adults with IBS, patients took one capsule, either a peppermint-oil formulation or placebo, three to four times daily before meals for one month. Of those taking the peppermint oil, 79 percent experienced less severe abdominal pain compared to 43 percent taking placebo; 83 percent had reduced stool frequency vs. 32 percent taking placebo; and 79 percent had less flatulence vs. 22 percent taking placebo (Journal of Gastroenterology, 1997, vol. 32, no. 6). A typical dose is one to three enteric-coated capsules twice daily between meals.

Probiotics, or beneficial bacteria, such as acidophilus (Lactobacillus acidophilus) and bifidobacterium (Bifidobacterium bifidum), occur naturally in the gut and aid in digestion by supporting intestinal function. These friendly flora are sometimes destroyed by antibiotics and foods containing chemicals and pesticides. Supplementing the diet with probiotics can keep the counts of these bacteria high.

A recent study looked at the efficacy of the probiotic strain L. plantarum in patients with IBS. Twenty patients received the L. plantarum and 20 patients received a placebo over a period of four weeks. At the end of the study, 100 percent of the patients who received the probiotic treatment reported decreased abdominal pain, compared to only 11 patients from the placebo group. In addition, six out of ten patients experiencing constipation reported normalized stools after taking the L. plantarum (European Journal of Gastroenterology and Hepatology, 2001, vol. 13, no. 10).

Essential fatty acids (EFAs) are also critical for digestion. Research shows that EFAs can ease intestinal inflammation and contribute to better nutrient absorption. EFA-rich foods include flaxseed and hemp seed oils.

Digestive enzymes are key to proper GI function and are typically available as blended formulas. Those who experience excess gas from dairy products can try chewing a lactase tablet before eating. If beans and legumes are your problem, try sugar-digesting enzymes, such as sucrase, maltase, lactase or amylase.

Other supplements aid specific intestinal complaints. Chamomile (Matricaria chamomilla) acts as an anti-inflammatory, so it is often used for patients with inflammatory bowel disease. The typical dose is 10-15 grams per day. Those with stomach or intestinal disorders may not absorb enough vitamin B12. In this case, 2.4 mcg should be taken daily, according to the National Institutes of Health.

Exercise is another important factor in maintaining a healthy digestive system. Regular exercise can act as an intestinal stimulant and a stress reducer. During physical activity, the stomach and intestines relax.

Bowel health is clearly an integral aspect of well-being. When the gastrointestinal system is out of balance, the whole body is affected. Fortunately, many of the symptoms and causes of bowel distress can be alleviated through diet and lifestyle changes. If you suspect you may have an intestinal disorder, it pays to go with your gut and seek the advice of a professional.

Editor, writer and visual artist Patti Woods is the former managing editor of Better Nutrition.