I think it is not impossible to lose weight with konjac, which needs long-term persistence. For example, take it for a month, during which you should adjust your diet and cooperate with exercise. That is to say, the effect will not be seen immediately. Look at the introduction first:

Amorphophallus konjac is commonly known as Amorphophallus konjac, and its real name is Amorphophallus konjac. It is described in the Shu Du Fu written by Zuo Si in Jin Dynasty, and also recorded in the Materia Medica in Song Dynasty. It is said that Wu Zhongsheng's konjac is also called ghost taro, which was introduced to Japan in ancient times and is called the devil's head. It was only a few decades ago that the strange name konjac was adopted. Botanically, Amorphophallus konjac is a perennial herb of Araceae, belonging to the same family as taro. At present, there are hundreds of varieties. In our country, people use its bulbs to cut into pieces, dry them, and grind them into powder to eat. According to Compendium of Materia Medica, konjac can cure carbuncle, quench thirst with wind toxin, lower blood pressure, inhibit cholesterol, and effectively inhibit breast cancer and colorectal cancer. The main component of konjac is glucomannan, but the content of refined powder varies greatly among different varieties. The compound made of polymer technology has strong swelling power (80- 120 times of its own weight after being dissolved in water), and will form a film on the inner wall of the intestine after entering the intestine, which can prevent the absorption of neutral fat, promote the excretion of lipid-like, increase food paste, produce satiety, reduce eating, reduce heat absorption, and reduce and delay the diffusion and absorption of glucose. Amorphophallus konjac, commonly known as slimming fiber, contains a "Hyman oil" substance, which can regulate lipid metabolism in human body and reduce blood lipid.