The World Health Organization has long classified alcohol as a Class I carcinogen, and the main evidence comes from two sources. The results of large epidemiological studies show that the more people drink, the higher their chances of getting cancer. Then there is the animal test, adding alcohol to the drinking water of rats, the cancer rate of rats increased significantly, and the question of how alcohol causes cancer looks simple, but not many people actually know the answer, even those who call for abstinence from alcohol, many of them actually do not know why drinking causes cancer, in fact, alcohol itself is not a carcinogen, what is really dangerous is that its metabolite acetaldehyde in the body is an obvious carcinogen. Currently, acetaldehyde has at least two important carcinogenic factors, namely, acetaldehyde can directly bind DNA to cause DNA mutation and acetaldehyde can cause cell death in the body, induce chronic inflammation and cell replication, and increase the probability of cancer. For Chinese people drinking alcohol is more likely to cause cancer because 60% of Asians lack the enzyme acetaldehyde conversion, and the slower the conversion rate of acetaldehyde lacking acetaldehyde and the longer it stays in the body, the more harmful it is to the human body. On the issue between cancer and health, the World Health Organization has long been the official conclusion is five words, the less wine the better. The World Health Organization collaborative study points out that under normal circumstances, men should drink no more than 20g of pure alcohol per day, and women should drink even less. If drinking cannot be avoided, experts suggest that it is best to try to choose a lower alcohol concentration to drink, not to drink on an empty stomach, and you should eat foods rich in vitamins and high protein before drinking.