Investigators in Berlin, Germany, have found that chewing sugar-free gum often enough can lead to substantial unintended weight loss. But that weight loss doesn't come without the side effects of chronic diarrhea and other possible bowel problems.

According to Juergen Bauditz, MD, of the University of Berlin, patients who chewed between 16 and 20 sticks of sorbitol-sweetened gum daily lost about 20% of their usual body weight. However, Dr. Bauditz and colleagues cautioned that only a small percentage of people who chew sugar-free gum develop diarrhea or substantial unintended weight loss. They contend that since "side effects are usually found only within the small print on foods containing sorbitol, consumers may be unaware of its laxative effects."