You would think from reading the headlines that a glass of red wine is almost as good for your health as a plateful of vegetables. Moderate drinking is good for your heart, but some studies show that it may increase the risk for cancer.
New research: The Million Women Study, which followed 1.3 million women for an average of seven years, found that about 13% of cancers—affecting the breast, mouth, throat, rectum, liver and esophagus—could be linked to alcohol. Women who consumed the most alcohol were the ones most likely to get cancer, but even one drink a day increased risk.
Researchers have known for a long time that heavy drinking is linked to cancer. Examples: At least 70% of patients with mouth cancer are heavy drinkers. People who have five or more drinks a day are more likely to get colorectal cancers and cancers in the upper digestive tract.
Moderation lowers the risks but doesn’t eliminate them. Cancers of the mouth and esophagus have been linked to as little as two drinks a day. An analysis in American Journal of Epidemiology concluded that men who have three or more drinks daily have a 41% increased risk for cancer-caused mortality. Women who have two or more drinks daily increase their risk by 20%.
It’s not yet known precisely how alcohol increases cancer risks. A toxic chemical called acetylaldehyde, produced when alcohol is metabolized (broken down) in the body, may damage genetic material and prevent cells from repairing the damage. In addition, alcohol metabolism produces free radicals that cause cell damage and inflammation, which can promote cancer.
There also appears to be a hormonal link. Alcohol may increase levels of estrogen and other hormones. This could be the reason that women who drink have a higher risk for breast cancer than nondrinkers.
Some people may have genetic variations that make them more or less likely to develop alcohol-related cancers. A study of heavy drinkers found that those who did not develop cancer had a genetic variation that enabled them to metabolize alcohol faster than those without the variation.
You may ask, “Why drink if it causes cancer?” To answer that question, it is helpful to understand the following…
The risks overall are small. Only 3.5 percent of cancer deaths world-wide (230,000 a year) are attributable to alcohol. But 90% of those deaths in men could be avoided if they drank no more than two alcoholic drinks a day and 50% of the deaths in women could be avoided if they drank no more than one drink a day.
Good for the heart. Alcohol increases levels of HDL “good” cholesterol. It reduces the formation of blood clots and helps dissolve clots that have already formed. Moderate drinking results in a sharp decrease in heart attack risk (40% to 60%).
Study limitations. Most studies that have linked alcohol to cancer are epidemiological studies. Large groups of people fill out questionnaires about their alcohol consumption and other lifestyle factors. Then researchers track their health over time.
Answers to this type of questionnaire can be inaccurate. People either don’t remember correctly or tell researchers what they think they should say.
The type of drink doesn’t matter much. Beer, whiskey, vodka and the like have similar effects on cancer risks. However, the resveratrol in red wine, which has been linked to cardiovascular health, also may prevent cancer by repairing cell damage. But you may have to drink more than moderately to get enough resveratrol, and that is not advisable.
All of the benefits of alcohol, including the cardiovascular benefits, evaporate when people drink too much. Even if you drink moderately (no more than two drinks daily for men or one daily drink for women), alcohol might help or hurt, depending on other factors.
Consider…
Your personal and family health history. A vigorous 20-year-old with healthy habits and no family history of heart problems probably won’t benefit from drinking. On the other hand, consider a 55-year-old who doesn’t exercise or eat a nutritious diet and who also has a family history of heart disease. This person might benefit from a daily glass of wine. The slightly increased risk would be offset by the cardiovascular benefits.
Or a woman with a family history of breast cancer might decide that it’s too risky to drink. A woman without this history might feel comfortable having one drink a day.
Always talk with your doctor about the potential benefits and risks of alcohol for you.
Drinking patterns. People who drink a lot at once, and do this consistently over the years, probably have more organ damage and greater cancer risk than those who drink smaller amounts over time. Let’s say one man drinks nothing during the week but has seven drinks on the weekend…and another man has one drink a day every day. Their weekly average is the same, but the health effects likely will be different.
Eat before you drink. If you have food in your stomach, alcohol is absorbed more slowly and the liver breaks down alcohol at the rate of about one drink per hour. Drinking on an empty stomach causes alcohol to move more quickly into the liver, potentially causing cell damage.
