By Their Gas Shall Ye Know Them

If you're worried about getting fat from eating junk food, that may be the least of your worries. Scientists now suspect that a high-meat and junk food diet may cause the overgrowth of undesirable intestinal bacteria, which can ultimately lead to bowel disease or even cancer.

Bacteria in the intestines normally produce a mixture of gases, including methane, but scientists studying the composition of intestinal gas noticed that some people did not produce methane. Further inquiry revealed that sulfate-consuming bacteria had replaced methane-producing bacteria in these people. Wondering if diet could be responsible, people with methane-producing bacteria were fed a diet rich in sulfate-containing foods, and, sure enough, the number of sulfate bacteria shot up. The foods found to nourish sulfate-loving bacteria were high protein foods and foods with sulfur-containing preservatives.

There is evidence that high numbers of sulfate-consuming bacterial in the intestines may lead to disease. The levels of sulfate bacteria were measured in healthy people and in those with ulcerative colitis, a serious and fairly common inflammatory disease of the bowel. Ninety-six percent of the colitis sufferers harbored sulfate bacteria, compared to only 50% of the controls.

Meat and other high protein foods release sulfur-amino acids during digestion. As meat consumption increases from about 2 ounces to about 1 1/3 pounds per day, sulfides in the feces increase tenfold. A high-meat diet has previously been linked to colon cancer, and researchers now suspect that sulfur-consuming bacteria may contribute to the disease.

Vegetarians have a low incidence of colon cancer. They still eat protein, but protein from vegetable sources probably does not lead to cancer because it occurs in foods that are also rich in carbohydrate. Carbohydrates nurture beneficial bacteria and encourage quick passage of foods through the gut.

Other sources of sulfur in the diet are the sulfur compounds commonly added as preservatives to hundreds of different commercial foods, from beer to dried fruit to instant soup.

Researchers believe that the most effective way to purge the intestines of disease-causing bacteria is to change the diet by reducing meat and getting off junk foods.   Based on information in: New Scientist, 8-Aug-98