German doctors solved two mysterious cases of rapid - and dangerous - weight loss from diarrhea once they determined that the cause was chewing too much sugar-free gum containing the artificial sweetener sorbitol.

The doctors were puzzled at the cause of the severe diarrhea that led a 21-year-old woman to lose 24 pounds and a 46-year-old man to lose 46 pounds. When they asked both patients about their chewing habits, they discovered that both were heavy users of sugar-free gum. Sorbitol in large quantities has been known to increase the risk of diarrhea.

They learned that the woman had been chewing 15 to 20 sticks of gum a day, each stick containing 20 grams of sorbitol. The man was up to 20 sticks a day. The consequences were dramatic: both patients visited the bathroom at least 10 times a day.

Once doctors found the culprit, both patients recovered rapidly. The woman dropped to one bowel movement per day and regained 15 pounds over the next year. The man also went to one movement a day and regained 11 pounds of his lost with half a year.

Sorbitol rarely shows up in U.S.-made chewing gum or sweets. The preferred artificial sweetener here is aspartame (NutraSweet). The Food and Drug Administration says that consumption of more than 50 grams a day of sorbitol can lead to diarrhea.

Source: HealthDay, January 2008