You probably know that too much alcohol is bad for your health. But for certain cancers, even modest amounts may increase risk. Here’s the latest research on how alcohol links to cancer and what you can do.
Alcohol increases the risk of (at least) six cancers.
After thoroughly reviewing studies from around the world, AICR research shows that alcohol increases the risk of six cancers: colorectal, breast, esophageal, liver, stomach and oral (technically mouth, larynx and pharynx cancers).
For breast, colorectal, oral and stomach cancers, the increased risk is seen at even low levels of regular drinking. For liver and stomach cancer, increased risk starts at three alcoholic drinks per day.
For lower cancer risk, all types – yes, even red wine – pose risk
The evidence that all types of alcoholic drinks increase the risk of cancers has grown over the years. That list includes wine, beer, vodka and other hard liquors. The World Health Organization estimates that from 4 percent to approximately 25 percent of cancers are attributable to alcohol worldwide.
In 2012, approximately one in every 20 deaths worldwide was attributable to alcohol, according to the World Health Organization. That translates into approximately 412,500 individuals.
Alcohol is classified as a carcinogen
There are many types of alcohol substances, but the one in wine, beer and other beverages we drink is a type called ethyl alcohol or ethanol. Back in 1988, the International Agency for Research on Cancer of the World Health Organization classified alcohol as a carcinogen, which means it has the potential to cause cancer.
There are a lot of different ways alcohol can increase cancer risk:
- Scientists are still working to figure out how alcohol promotes cancer growth, and there are likely multiple ways. Scientists have identified several possible theories, including:
- Alcohol is converted into a substance called acetaldehyde, a compound which can directly damage our DNA. That, in turn can lead to cancer cells developing.
- The alcohol molecule can physically help carry other cancer-causing substances into cells.
- Too much alcohol can lead to low levels of vitamin D and other nutrients, which play a role in health and lowering cancer risk.
- For liver cancer, high amounts of alcohol can cause cirrhosis, a condition strongly linked to liver cancer.
- For breast cancer, alcohol may lead to higher estrogen levels, which could help cancer cells to grow.
Combining alcohol with smoking is particularly harmful for mouth and throat cancers, dramatically raising the risk of these cancers as alcohol increases ability of tobacco carcinogens to get in to cells and create damage.
If you drink alcohol, keep it to moderate amounts.
For lower cancer risk, AICR recommends not to drink alcohol. However, AICR experts who analyzed the global research recognize that modest amounts of alcohol may have a protective effect on coronary heart disease.
That is why AICR recommends that if you do enjoy alcoholic drinks, limit your consumption to no more than two drinks a day for men and one drink a day for women.
Sources: World Health Organization. http://www.who.int/substance_abuse/publications/global_alcohol_report/msb_gsr_2014_1.pdf