Does alcohol cause cancer, or does it prevent it? Scientists have given us mixed messages; so it’s confusing, to say the least. It has always seemed to depend on the type of cancer, the kind of alcohol, and the amount of alcohol consumed.
For example, red wine consumption has been shown to reduce the risk of breast cancer. In that study, participants drank 8 ounces of red wine each evening.
However, the American Cancer Society (ACS) states on its website that more than 100 epidemiological studies that looked at the association between alcohol consumption and the risk of breast cancer consistently found an increased risk of breast cancer associated with increased alcohol intake. In other words, the more you drink, the higher your risk of breast cancer.
A meta-analysis of 53 of these studies showed that women who drank more than 45 grams of alcohol per day – about 3 drinks – had 1.5 times the risk of developing breast cancer as nondrinkers. This represents a modest risk.
According to the ACS, alcohol consumption has also been linked to the following cancers:
- Head and neck
- Liver (a very well-known association)
On the other hand, increased alcohol consumption is associated with a decreased risk of renal cell (kidney) cancer and non-Hodgkin lymphoma.
Well, a new review in the journal Addiction suggests that alcohol is not only linked to seem different types of cancer, it may actually cause them.
Researchers looked at a number of long-term studies, including ones from the World Cancer Research Fund/American Institute for Cancer Research, the World Health Organization’s International Agency for Research on Cancer, and the Global Burden of Disease Alcohol Group.
Lead researcher Jennie Connor, of the University of Otago in New Zealand, said that she and her colleagues found that drinking alcohol was routinely linked to cancer of the oropharynx, larynx, esophagus, liver, colon, rectum, and, in women, the breast.
“There is strong evidence that alcohol causes cancer at seven sites, and probably others.” 
While the review doesn’t actually prove alcohol causes cancer, Connor said the whole body of literature taken together gets awfully close to it – certainly closer than one study alone – without randomly assigning people to drink alcohol or abstain entirely.
After all, that would be completely unethical.
“The highest risks are associated with the heaviest drinking but a considerable burden is experienced by drinkers with low to moderate consumption.”
So there’s really no safe level of alcohol consumption, according to the 10 years’ worth of research.
Specifically, the review found:
- Drinking 50 grams of alcohol per day – approximately 2.6 beers or about 3, 6-ounce glasses of wine – results in a 4 to 7 times increased risk of cancer in the oropharynx, larynx, and esophagus, and a 1.5 times greater risk of the others, compared to consuming no alcohol at all.
- Alcohol may cause skin, prostate, and pancreatic cancer. 
Conner said the purported benefits of alcohol are “seen increasingly as … irrelevant in comparison to the increase in risk of a range of cancers.”
It isn’t clear just how alcohol may cause cancer; but one mechanism, at least for cancers of the mouth, pharynx, larynx, esophagus and liver, may be due to DNA damage from acetaldehyde, a metabolite of alcohol and a carcinogen. 
Another potential mechanism is likely due to compounds in alcohol that may facilitate entry of other types of carcinogens, such as those from tobacco, into the mucosal cells that line the upper digestive tract. Considering how many people smoke cigarettes and drink at the same time, it’s a pretty sobering thought.
As for breast cancer, alcohol may cause the disease by increasing levels of reproductive hormones, like estrogen, which can increase cell division.
Regardless of the mechanisms, it doesn’t seem to matter whether you drink beer, wine, or hard liquor; the risk is the same.
Well, that’s it, folks. No more alcohol for me! I’m never touching the stuff ever again, for as long as I live!
I don’t want cancer, but I like a beer or a glass of wine once in a while. Doctors and scientists, too, recognize that most people aren’t going to completely rid their lives of alcohol. But if you’re a big drinker, it might be a good idea to cut back.
Dr. Jana Witt, of Cancer Research UK, offered these tips:
“Having some alcohol-free days each week is a good way to cut down on the amount you’re drinking. Also, try swapping every other alcoholic drink for a soft drink, choosing smaller servings or less alcoholic versions of drinks, and not keeping a stock of booze at home.” 
 UK Guardian
 USA Today
 CBS News
Julie Fidler is a freelance writer, legal blogger, and the author of Adventures in Holy Matrimony: For Better or the Absolute Worst. She lives in Pennsylvania with her husband and two ridiculously spoiled cats. She occasionally pontificates on her blog.