1, diet adjustment: During the period of losing weight, we changed our eating habits, such as reducing the intake of high-fat foods, and the body fat will be decomposed into oily substances and excreted with the stool.
2, oral drugs or supplements: some diet drugs or supplements cause color changes in the stool, including blackening or oily substances.
3, gastrointestinal bleeding: Sometimes, black stool is a sign of upper gastrointestinal bleeding such as stomach and duodenum, because iron in the blood will appear black after oxidation in the intestine.
4, intake of food containing melanin: eat some foods containing a lot of melanin, such as pig blood, duck blood, black sesame and so on. It can also lead to black stool.
5. Excessive animal fat intake: If the diet contains a lot of animal viscera or high-fat meat, it will lead to oily stools.
6. Intestinal diseases: Although not common, some intestinal diseases can lead to similar situations.