In their recent public meeting, members of the Dietary Guidelines Advisory (DGA) Committee forecast changes to the prevailing advice on alcohol. Long instructed to limit consumption to no more than two drinks per day, “if they choose to consume alcohol,” American men will now be told to cut themselves off after just a single serving of beer, wine, or liquor. The new guidelines also have advice for anyone drinking to lower the risk of cardiovascular disease or achieve other health benefits: don’t. According to the Committee, “at all levels of consumption, drinking less is generally better for health than drinking more.”
The committee deserves credit for helping to clear the air on a topic of considerable consumer confusion. For decades, the Dietary Guidelines for Americans have helped to fuel the myth that moderate alcohol consumption contributes to a longer life. As recently as 2010, the DGA’s said things like “Strong evidence from observational studies has shown that moderate alcohol consumption is associated with a lower risk of cardiovascular disease.” The more recent guidelines dropped that statement, but they also stopped referring to the research linking alcohol and cancer. Undoubtedly, many readers were left wondering whether health benefits associated with light drinking outweigh cancer and other risks.
Our best evidence indicates that they do not. All of that “strong evidence” demonstrating the cardiovascular benefits of the occasional drink has not aged well. Researchers have documented a number of biases in the old observational alcohol studies.
New “Mendelian randomization” studies, which compare populations with genetic variants associated with lower alcohol consumption — and are not susceptible to these biases — tell a different story. Comparing these “alcohol allergic” subjects to those with more conventional genotypes, alcohol actually appears to increase the risk of some cardiovascular diseases. All of this has led experts like the Centers for Disease Control and Prevention to conclude that “it’s impossible to conclude” whether the observed benefits in the studies “are due to moderate alcohol consumption or other differences in behaviors or genetics between people who drink moderately and people who don’t.”
By contrast, the link between cancer and “alcohol use — whether light, moderate, or heavy” is “firmy established.” The Dietary Guidelines for Americans should reflect this scientific reality.
Unfortunately, the upcoming recommendations, while a significant improvement, may fall short of their potential if, like the 2015 Guidelines, they omit a frank discussion of alcohol’s contribution to cancer. Popular media has bombarded us with click-able stories on the potential health benefits of alcohol. But alcohol’s link to cancer, although long-established and significant, has flown under our collective radar. According to recent surveys, less than half of adults identify alcohol as a cancer risk. Indeed, even among cancer survivors, awareness of the risks associated with alcohol is far from universal.
The lack of awareness reflects not just media bias but also public policy. We are warned that all kinds of substances cause cancer. Under California’s Proposition 65, retailers briefly had to include a cancer warning on coffee, not for the coffee itself but for a chemical called acrylamide that forms during the roasting process. However, because of an outdated federal law, which my group Consumer Federation of America and other public interest groups are trying to change, alcoholic beverages do not carry a cancer warning.
That is ironic, and unfortunate because alcohol is not like coffee. It significantly contributes to cancer risk. Researchers estimate that drinking alcohol is the third most important cause of cancer that is within a person’s control, behind smoking and obesity; each year alcohol consumption causes more cancer deaths than exposure to ultraviolet radiation. Alcohol’s cancer risk increases with heavier levels of consumption, but the science shows that even “moderate” alcohol consumption — no more than one drink per day — increases the risk of developing several different types of cancers. The evidence linking moderate drinking and breast cancer is particularly longstanding.
The Dietary Guidelines for Americans should present this evidence, and include a statement such as: “For cancer prevention, the safest level of alcohol consumption is zero.” This would help Americans to understand recommendations to drink less, and persuade many not to start a drinking habit in the first place. With accurate information, consumers will take better action to protect their interests, including their health, and public health across the board will improve.
Thomas Gremillion is the director of Food Policy at the Consumer Federation of America.