How dose Alcohol cause cancer?

How does alcohol cause cancer? What’s the mechanism?

As soon as people drink alcohol, it metabolizes to a compound called acetaldehyde. This is from the microbes we have in the gastrointestinal tract, and it starts in the mouth. After a few minutes, the concentration of acetaldehyde goes up immediately in the saliva, gastric juices, colon, and in the blood. That’s a potent genotoxic compound. It can affect DNA, and it may cause cancer. Smoking affects the microbiome, and that can increase the levels of acetaldehyde produced in the mouth. So, smoking is synergistic in that way.

There are other factors as well. It can increase inflammation, cause oxidative stress, and alcohol can affect sex hormone levels. That can change the risk of breast cancer. Alcohol can also reduce absorption of some nutrients that are helpful to repair DNA damage — for example, folate.

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