Glucomannan is the Western name for vegetable fibers derived from an Asian plant family known as konjac. Glucomannan does not dissolve in water, but forms a thick, gooey gel when exposed to fluids. The body does not digest glucomannan, so the resulting large soft mass moves through the intestines and may trigger intestinal muscle contractions. Therefore, glucomannan is thought to be an effective bulk-type laxative, even though it may take up to 12 hours to be effective. Glucomannan vs. Obesity and Cholesterol Glucomannan has also been studied for treating obesity, diabetes, and high cholesterol. Studies in both adults and children with severe obesity showed varying degrees of weight loss associated either with taking supplemental glucomannan or with replacing some of the usual diet with foods made from glucomannan konjac flour--the dried and ground tuber underground stem of the plant. Generally, glucomannan is believed to discourage overeating because it creates a feeling of fullness a
