U.S. Surgeon General Vivek Murthy, M.D., issued an advisory last week naming alcohol as a leading preventable cause of cancer and calling on Congress to update the warning labels on alcoholic beverages to include this information.
The connection between alcohol and cancer is news to many in the general public – in fact, the advisory points out that only 45% of Americans are aware of it, even though research linking alcohol with cancer dates to the 1980s.
The advisory stated that alcohol increases the risk of certain head and neck cancers, including oral cavity, pharyngeal and laryngeal; esophageal; liver and colorectal cancer; and, in women, breast cancer. In fact, the surgeon general's advisory reports that more people die in the U.S. of alcohol-related cancer than alcohol-associated traffic crashes.
And yet, alcohol has been consumed throughout human history. It's an integral part of many rituals, celebrations and occasions, and many people consume alcohol with no apparent ill effects. However, we are learning more about how alcohol misuse can be harmful to one's general health.
Putting the risk in context is key, said two researchers at the Charleston Alcohol Research Center (ARC) at the Medical University of South Carolina. ARC scientists research how heavy drinking changes the brain chemistry circuitry, with the end goal of improving how alcohol use disorder can be treated. It's been continuously funded by the National Institute on Alcohol Abuse and Alcoholism (NIAAA) since 1995.
Howard Becker, Ph.D., professor of Psychiatry and Neuroscience and ARC director, said he hopes that the advisory encourages people to take a look at their drinking habits and honestly evaluate whether they're causing problems.
"It's a good idea to reevaluate what your alcohol drinking behavior is, and if you think that it is contributing to increased weight, increased blood pressure, difficulty sleeping, since you may find that all those things improve just with cutting down," he said. "And, it may have beneficial effects in terms of gastrointestinal issues and perhaps lowering the risk for cancer."
"I see this as an opportunity to once again talk about the breadth of impact that alcohol can have on one's health, especially if you're drinking in a hazardous way."Howard Becker, Ph.D.
Charleston Alcohol Research Center
He noted that changing patterns of heavy drinking have already affected clinical care needs.
"I think the data about liver disease are really alarming," he said. "The latest statistics are showing that those individuals who require liver transplant due to heavy alcohol use now may be in their 40s and 50s, which was unheard of a few decades ago."
Liver cirrhosis, a buildup of scar tissue that can be caused by heavy alcohol use, is a risk factor for liver cancer.
The surgeon general's advisory suggests that the recommended maximum number of drinks per day to prevent disease be revised downward, although it doesn't make a specific recommendation on what that number should be.
Raymond Anton, M.D., Distinguished University Professor Emeritus and past ARC co-scientific director, said that people typically underestimate how much they drink. The official definition of one drink is 5 ounces of wine, 12 ounces of beer or 1.5 ounces of liquor, but people often serve more or don't remember how many drinks they've consumed correctly. A cocktail content calculator on the NIAAA website shows how a more generous pour can quickly lead to people consuming as much as double the amount of alcohol as they may think they are drinking.
This underestimation does make it difficult to determine a precise threshold at which health risks increase and may vary depending on other personal or genetic factors, he said. But there are a few groups who would especially benefit from this information, Anton said.
In recent years, alcohol use among women, including heavy drinking, has almost caught up with that of men. But those women who are already at higher risk of breast cancer, perhaps because of family history, estrogen exposure or dense breast tissue, may want to cut back or stop drinking altogether. Anton said that those with early mammogram findings of potential or early breast cancer should seriously consider the effect of alcohol on its further development.
Alcohol consumption has also increased among older Americans, raising concerns about potential risks. They may, therefore, want to reconsider their drinking habits to prioritize their health. Anton, for example, lives in a coastal community popular with an influx of relatively recent retirees. "It's almost like a second youth for them. The kids are settled, and work has diminished so they're ready to do a little more partying like they did when they were younger," he said.
But as people grow older, their bodies become less resilient in terms of cellular repair mechanisms, exacerbated by alcohol consumption, leading to a higher cancer risk, Becker said. As people age, their livers become less efficient at metabolizing alcohol, Anton explained. Additionally, prescription medications can interfere with alcohol metabolism, raising blood alcohol levels for each drink consumed.
People who smoke often drink as well, and using the two together multiplies their cancer-causing effects, likely leading to a higher risk for mouth and throat cancers, among others.
Finally, people who drink heavily – currently defined as men who have five or more drinks per day and women who have four or more drinks per day – should reevaluate their intake since they are at higher risk for many alcohol-related health consequences, including cancer, the researchers said
This group often does not focus on their alcohol intake, Becker said, because they haven't yet had to deal with many health, social or personal consequences.
"There are a lot of heavy drinkers out there," Anton added. "They sort of fly under the radar, in a sense, in that they're not necessarily experiencing a lot of social consequences." They also often go unrecognized from a clinical perspective.
Anton would like to see health care providers begin to educate patients about alcohol use, utilize alcohol consumption lab tests to assess consumption more accurately, offer brief counseling on alcohol reduction, and, if necessary, refer patients for further evaluation by specialists, such as those at the MUSC Center for Drug & Alcohol Problems.
Although cancer is an important risk to consider, it is only one of many issues that alcohol can cause, Becker said.
"I see this as an opportunity to once again talk about the breadth of impact that alcohol can have on one's health, especially if you're drinking in a hazardous way," he said. "So not necessarily social drinking per se, but heavy drinking. Those who hit that level of consumption are putting their health at high risk in a variety of different ways. It may just be elevated blood pressure. It could be increased body weight. It could be a whole host of different things that are aggravating factors to what one would consider good health."
Cancer is a serious consequence of alcohol consumption, underscoring the importance of the surgeon general efforts to raise awareness of this public health issue and empower Americans to make informed choices regarding their health and longevity, Anton said.
