No amount of alcohol is safe for cancer
Excerpted from the New York Times, January 13, 2023
Why is alcohol so harmful?
Scientists think that the main way alcohol causes health problems is by damaging DNA. When you drink alcohol, your body metabolizes it into acetaldehyde, a chemical that is toxic to cells. Acetaldehyde both “damages your DNA and prevents your body from repairing the damage,” said Marissa Esser, who leads the alcohol program at the Centers for Disease Control and Prevention. “Once your DNA is damaged, then a cell can grow out of control and create a cancer tumor.”
Alcohol also creates oxidative stress, another form of DNA damage that can be particularly harmful to the cells that line blood vessels. Oxidative stress can lead to stiffened arteries, resulting in higher blood pressure and coronary artery disease.
“It fundamentally affects DNA, and that’s why it affects so many organ systems,” Dr. Naimi said. Over the course of a lifetime, chronic consumption “damages tissues over time.”
What types of cancer does alcohol increase the risk for?
Almost everyone knows about the link between cigarette smoking and cancer, but few people realize that alcohol is also a potent carcinogen. According to research by the American Cancer Society, alcohol contributes to more than 75,000 cases of cancer per year and nearly 19,000 cancer deaths.
Alcohol is known to be a direct cause of seven different cancers: head and neck cancers (oral cavity, pharynx and larynx), esophageal cancer, liver cancer, breast cancer and colorectal cancer. Research suggests there may be a link between alcohol and other cancers as well, including prostate and pancreatic cancer, although the evidence is less clear-cut.
For some cancers, such as liver and colorectal, the risk starts only when people drink excessively. But for breast and esophageal cancer, the risk increases, albeit slightly, with any alcohol consumption. The risks go up the more a person drinks.
“If somebody drinks less, they are at a lower risk compared to that person who is a heavy drinker,” said Dr. Farhad Islami, a senior scientific director at the American Cancer Society. “Even two drinks per day, one drink per day, may be associated with a small risk of cancer compared to non-drinkers.”