Constipation may produce harmful substances, anal fissure, hemorrhoids and other hazards to the body. 1. Produce harmful substances: constipation, the body’s excreta in the rectum, colon and other lower digestive tract for a long time gathering, fermentation reaction occurs to produce a large number of methane, ammonia and other harmful substances, stimulate the nervous system caused by memory loss, dizziness, fatigue and other symptoms. 2. Anal fissure: constipation can cause feces to remain in the intestinal tract for too long, fecal matter accumulates together, and when defecating, large, hard feces reaches the anus, and the patient can suffer fissures due to excessive expansion of the anus during the process of straining to defecate. 3. Hemorrhoids: Long-term constipation can lead to elevated venous pressure in the rectum and anus, resulting in enlarged veins and thinning of the vein walls, which can lead to the formation of hemorrhoids. If the patient exists constipation, it is recommended to adjust the diet, go to the hospital in time, for active treatment to avoid adverse effects.