Why do beans make us pass gas?

Nutrition experts are constantly encouraging all of us to eat more vegetables. People who eat the most produce are about 15 percent less likely than those who eat the least to develop heart disease and similar problems (Critical Reviews in Food Science and Nutrition, May 24, 2017).

People who follow a DASH (Dietary Approaches to Stop Hypertension) diet rich in vegetables have lower blood pressure and are less susceptible to diabetes. A DASH diet includes at least four servings a day of vegetables and four of fruits. The much-touted Mediterranean diet also is loaded with veggies.

These diets also are full of beans. Legumes such as beans and lentils are a healthful substitute for meats. In addition to the protein they provide, they are great sources of fiber that can help nourish the microbes in our digestive tracts.

Unfortunately, though, there is a drawback to a bean-heavy menu. You may already have guessed it: gas. Legumes contain lots of compounds called oligosaccharides. So do vegetables such as artichokes, broccoli, cabbage, chickpeas, garlic, leeks, okra and onions.

Humans can’t break down these complex sugars. But bacteria in the large intestines can. They love oligosaccaharides and use them as food. One outcome is gas – hydrogen, carbon dioxide and, in some people, methane.

How can you get the benefits of beans, lentils and vegetables such as brussels sprouts or broccoli without suffering from flatulence? Some cultures have traditional flavorings that are purported to counteract gas. In India, asafetida (hing) is frequently added to legume dishes. Turmeric also is reputed to have digestive benefits. Mexican chefs put the herb epazote in their pots of beans.

Ginger and fennel also are popular for this purpose. Either can be added to the legume dish or made into a tea for consumption between meals.

If you are cooking beans and want to minimize their gas-producing power, here is a suggestion: Cover the beans with a generous amount of water. A ratio of 9 parts water to 1 part beans is recommended. Bring them to a boil, cook for three minutes and allow them to cool for four hours. Pour off the water, add plenty of fresh water and cook the beans for half an hour. Then discard this water and add more to cook the beans until they are done. This final cooking water also should be discarded to get rid of the oligosaccharides raffinose and stacchyose that cause gas.

If you are not in control of the cooking process, you might want to try taking Beano at the beginning of the meal. This product contains the enzyme alpha-galactosidase. This compound can break down the oligosaccharides and deprive intestinal bacteria of their fuel.

Food is not the only culprit for creating gas. Some medications also can contribute to flatulence. The weight-loss drug orlistat (Alli, Xenical) is notorious for this complication. Some antidepressants, including paroxetine, sertraline and venlafaxine, also may cause problems. For a longer list of medications that can trigger excess gas, you may wish to consult our “Guide to Digestive Disorders.” It also mentions other ways to combat flatulence and bloating. Anyone who would like a copy, please send $3 in check or money order with a long (No. 10), stamped, self-addressed envelope to: Graedons’ People’s Pharmacy, No. G-3, P.O. Box 52027, Durham, NC 27717-2027. It also can be downloaded for $2 from our website: www.peoplespharmacy.com.

Joe Graedon is a pharmacologist. Teresa Graedon has a doctorate in medical anthropology and is a nutrition expert. Their syndicated radio show can be heard on public radio. In their column, Joe and Teresa Graedon answer letters from readers. Write to them in care of King Features, 628 Virginia Drive, Orlando, FL 32803, or email them via their website: www.PeoplesPharmacy.com.

2018 King Features Syndicate, Inc.