Cancer-causing effects of alcohol more significant than possible cardiovascular benefits, study says

Many people see alcohol as having many social benefits, and some studies have even claimed to reveal the cardiovascular health benefits of certain kinds of alcohol like red wine or beer. But a new study from the journal Addiction says all of those so-called benefits are useless or non-existent because alcohol causes at least seven different types of cancer all throughout the body, and drinking even moderately can apparently increase your risk of developing the disease.

The authors said were motivated to conduct the research by the “patchy” way other studies have described the link between alcohol and cancer, instead of directly calling the relationship causal. They sought out to find a more definitive relationship with the drink and the disease.

The study looked at data collected by other analyses and even other meta-analyses taken from the International Agency for Research on Cancer over the last 10 years. Based on their analysis, the researchers identified seven areas of the body where they say the consumption of alcohol directly increases the risk of cancer: oropharynx, larynx, esophagus, liver, colon, rectum and breasts. And the more alcohol that was consumed, the higher the risk for cancer.

They estimated that alcohol was the cause of nearly 500,000 cancer deaths in 2012, and caused about 5.8 percent of the total amount of cancer deaths worldwide that year.

The increased risks were different for different types of cancer. Alcohol increased the risk for pharynx, mouth and esophagus (especially when coupled with smoking) than it did for colorectal, breast and liver cancers.

Stopping drinking can improve some of that risk, the researchers found. Within five years, former drinkers can see a 15 percent in the reduction of pharyngeal and laryngeal cancers. And people who stopped drinking also saw a 6 to 7 percent decrease per year in liver cancer risk.

The study also examined another question, of whether women who drink moderately have a smaller chance of developing breast cancer than women who drink very rarely. But the study pointed out that the risk of developing other kinds of cancer increase even with light consumption of alcohol, negating the possibility that moderate drinking could protect from breast cancer.

Beyond the definitive types of cancer named in the study, researchers also found a smaller connection between skin cancers, pancreas cancer and prostate cancer related to drinking.

The researchers hypothesized that it’s not the ethanol itself that causes cancer in humans, but that the human body’s metabolic product of ethanol processing, acetaldehyde, is carcinogenic. For women, the increased presence of estrogen in the body related to alcohol consumption could be what contributes to the rising breast cancer risk.

The researchers called for more investigation into the links between alcohol and cancer, especially given the prolific nature of alcohol consumption. They even decried potentially “orchestrated attempts” at “confus[ing] the public” with conflicting alcohol information.

“Promotion of health benefits from drinking at moderate levels is seen increasingly as disingenuous or irrelevant in comparison to the increase in risk of a range of cancers,” they wrote.

The researchers focused more on burden of the population-level risks than the individual risks. Since more people drink lightly or moderately than drink heavily, their individual risks might be minimized compared to individuals who consume alcohol more heavily, but the population-level risks are still high given the total number of drinkers.