December 30, 2012 | by Shawn Le
The holiday season, for many people, begins with feasting and closes out with one last all-night binge before New Year’s resolutions temporarily kick in. Research has swung back and forth about the health risks, and potential benefits, of alcohol consumption -- with each new study about a cup of good cheer seemingly contradicting the last.
To help put concerns about toasting the New Year into perspective, James Lacey, Ph.D., associate professor in City of Hope’s Division of Cancer Etiology, answers some questions about alcohol and cancer risk.
What cancer risks are associated with alcohol consumption?
Alcohol consumption has been reported to increase the risk of female breast cancer. Alcohol has also been linked with increased risks of digestive tract cancers: oral cancer, pharyngeal cancer, and cancer of the larynx, as well as some types of esophageal cancer.
The mechanisms aren't entirely understood, but the increase in breast cancer risk might be due to the ability of alcohol to increase circulating levels of estrogens (which of course are key factors in the development of breast cancer). For the digestive tract cancers, there is some indication that alcohol's metabolism into acetaldehyde – which has carcinogenic and mutagenic properties – might be the mechanism at work.
Many studies compare moderate drinking and heavy drinking. What is considered moderate?
In most studies, "moderate" is defined as one drink per day, based on the standard unit equivalents of 1 beer, 1 glass of wine, or 1 serving of hard liquor.
In most study results, heavy drinking is usually bad while moderate drinking can be either good or bad. If less is better, is not drinking at all the best?
There is no consensus answer to whether complete abstinence is better than moderate drinking. Moderate alcohol consumption has been reported to reduce the risk of coronary heart disease, which of course affects far more men and women than do breast cancers or the rare digestive tract cancers.
A real challenge with alcohol is that rarely is alcohol consumed independently of other factors that affect health and disease. On the negative side, alcohol can accompany smoking or other less-healthy behaviors – which manifest themselves as confounding in epidemiologic studies – so it's always tough to isolate how much of an observed effect is due to alcohol versus other related lifestyle factors.
The same can be said of alcohol's positive effects. Think of the Mediterranean diet or the French diet where lower caloric intake and healthy eating habits often include more daily consumption of wine than is typically seen in U.S. diets.
As far as I know, there have not been good studies that attempt to quantify the overall effects of alcohol on multiple chronic disease endpoints – breast cancer, coronary heart disease, liver disease, etc – at the same time, although I am currently working on a research grant that will propose to do just that.
How can we celebrate the New Year but still be mindful of our health?
The old mantra, "everything in moderation" still applies. There is certainly a place for good beer, fine wine, or special champagne on special events such as New Year's celebrations. Moderate consumption can help to make sure that the alcohol – just like a favorite meal or decadent dessert – adds to the occasion.
On the other hand, because most of the studies have looked at the benefits and risks of regular alcohol consumption, the person who usually doesn't drink alcohol but wants to join the toast should not have to worry about whether the alcohol they consume on New Year's Eve is going to increase their risk of developing cancer.
There has been something of a renewed focus on classic cocktails and mixed drinks in recent years, and part of this has been a resurgence in specialty mixers and high-quality tonics, creative fruit juices, and other mixed-drink ingredients. That's good news for those who enjoy cocktails and "mocktails," because there are now more options than ever for making mixed drinks that can be equally tasty with or without the alcohol.
Where can people go for more information about the risks and benefits of alcohol consumption?