Carbohydrates are made of sugars either alone or in combinations (starches) and before they can be absorbed, they must be broken down into single sugars. Vegetables, beans, nuts, cereals and other foods contain starches and sugars that should be absorbed in the upper intestinal tract. However, some of the carbohydrates cannot be broken down. If they are not absorbed in the intestines, they pass to the colon where bacteria ferment the carbohydrates to release gas.
Half of the world's population develops gas and cramping after drinking milk because they lack the intestinal enzyme that is necessary to break down the double sugar in milk called lactose. If lactose is not absorbed in the upper intestinal tract, bacteria ferment it in the colon to release gas. If you are lactose intolerant, you can avoid dairy products, but no one should avoid vegetables, beans and whole grains.
If you are bothered by gas when you eat beans, whole grains or vegetables, you may not have an adequate colony of friendly bacteria in your colon to break down the resistant starches in plants. If you have recently changed your diet to include more of these foods, give yourself a few weeks or even months to build up the bacteria you need to digest them without excessive gas. Recent research shows that normal intestinal bacteria make up approximatly 95 percent of the total number of cells in the human body. The good bacteria help to prevent bad bacteria from infecting you, and may help to prevent intestinal diseases such as ulcerative colitis, Crohn's disease or cancer.
If you have waited a reasonable time and are still bothered by excessive gas, check with your doctor. One study showed that Rifaximin, an antibiotic that cannot be absorbed from the intestines, can control many cases of excessive intestinal gas. However, this antibiotic is not available in North America; ask your doctor about using metronidazole instead.
Dr. Gabe Mirkin has been a radio talk show host for 25 years and practicing physician for more than 40 years; he is board certified in four specialties, including sports medicine. Read or listen to hundreds of his fitness and health reports at http://www.DrMirkin.com
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