Taking diet pills with oil in the stool is considered to be the result of diarrhea and intestinal toxin discharge. Many diet pills will contain laxative ingredients, which can stimulate the intestinal peristalsis to speed up after use. The intestines cannot absorb the nutrients and water in the food, so the stool will contain a lot of undigested food, and even some fatty foods will be excreted directly, and the stool will have oily substances in it. Some diet pills contain detoxifying and cleansing drugs that promote the excretion of toxins and waste in the intestines, allowing excess water and fat to be excreted from the stomach and intestines, resulting in oil in the stool. When using drugs to lose weight, you should pay attention to the safety of the drug, once the body adverse reactions, should promptly stop the drug, it is best to use diet combined with exercise to lose weight.