Konjac weight loss has its joys and its pains. The joy is that konjac does indeed have a weight loss effect, based on three reasons. First, because it absorbs water and swells, it can be processed into low-calorie gel-like foods, such as konjac tofu or konjac noodles, which helps to fill the stomach and increase satiety. Second, because it can delay gastric emptying, slowing down the digestion of mixed food and the rate at which postprandial blood sugar and lipids rise. Third, through its high viscosity, it prevents efficient contact between digestive enzymes and food components, and also slows down the rapid absorption of digested food, thereby reducing the rate of increase in blood sugar and lipids.
The pain is that processed konjac foods contain negligible protein, no starch, and no fat. Although they contain small amounts of minerals, these are bound by dietary fiber and have very low absorption and utilization rates. If used as a staple food, long-term consumption can easily lead to malnutrition.