Constipation refers to fecal retention in the intestines for a long time, often without constipation, prolonged defecation time or defecation difficulty due to defecation intention.
Healthy people are defecation once a day, stool soft shape, defecation unobstructed. Every 2-3 days or even a long time to defecate, this is called constipation.
Why can constipation lead to colon and rectal cancer? Modern medicine believes that there are the following aspects:
1. Constipation, especially long-term chronic constipation, dry feces often stay in the large intestine and can not be discharged in time, which will inevitably produce adverse mechanical physical stimulation on intestinal mucosa, resulting in inflammation of intestinal mucosa.
2. Under the action of intestinal anaerobes, a part of undigested fat and protein in the intestine can produce chemical carcinogens such as nitrosamines, phenols, ammonia, azobenzene, and toxic products such as indole, methylindole and hydrogen sulfide.
3. High fat can cause the increase of bile secretion. The bile acid can produce carcinogens such as deoxycholic acid under the action of intestinal anaerobes, and the degradation products of fat may also have carcinogenic or synergistic carcinogenic effects.