The efficacy and role of purple sweet potato: a, prevention and control of constipation, purple potato can prevent constipation, purple potato contains cellulose can promote gastrointestinal motility, help clean up the intestinal environment, effectively ensure intestinal cleanliness, smooth stool, timely discharge of toxins in the body, as well as other harmful substances. Second, enhance immunity, purple potatoes can enhance the body’s immunity, purple potatoes in the defense of Europe’s mucin can help prevent the occurrence of collagen disease, improve the body’s immunity. Third, protect the liver, purple potatoes have a very good role in protecting the liver, purple potatoes contain choloroside, can effectively inhibit carbon tetrachloride, to avoid carbon tetrachloride caused by acute liver damage, effective protection of the liver, purple potatoes detoxification function, can also help reduce the burden on the liver. Fourth, cancer prevention and anti-cancer, purple potatoes have good cancer prevention and anti-cancer effect, purple potatoes contain selenium, iron, etc., can help the body anti-fatigue, anti-aging, especially selenium can be absorbed by the body, enhance the body’s immunity, and help inhibit the growth of cancer cells, effective cancer prevention and anti-cancer.