Diarrhea generally will not lose weight, but prolonged diarrhea may cause weight loss. Diarrhea that is, diarrhea, mostly due to the increase in intestinal capillary permeability caused by the increased number of stools, diarrhea more often can lead to the body to lose a lot of water, resulting in weight loss. But because the body is losing water, not fat, so stop diarrhea, weight will return to normal. Therefore, diarrhea can not directly cause weight loss. If a patient experiences prolonged diarrhea, it may be caused by digestive diseases such as irritable bowel syndrome, chronic amoebic dysentery, and chronic bacillary dysentery. This kind of disease will cause the gastrointestinal tract to reduce the ability of digestion and absorption, unable to absorb the nutrients in the food, may cause malnutrition and lead to wasting. If diarrhea occurs, you should go to the hospital in time, under the guidance of the doctor for standardized treatment.