Alcohol Plays a Major Role in New Cancer Cases

THIS ARTICLE IS republished from The Conversation under a Creative Commons license.

A little bit of alcohol was once thought to be good for you. However, as scientific research advances, we’re gaining a clearer picture of alcohol’s effect on health—especially regarding cancer.

The complex relationship between alcohol and cancer was recently highlighted in a new report from the American Association for Cancer Research. The report’s findings are eye-opening.

The authors of the report estimate that 40 percent of all cancer cases are associated with “modifiable risk factors”—in other words, things we can change ourselves. Alcohol consumption being prominent among them.

Six types of cancer are linked to alcohol consumption: head and neck cancers, esophageal cancer, liver cancer, breast cancer, colorectal cancer, and stomach cancer.

The statistics are sobering. In 2019, more than one in 20 cancer diagnoses in the West were attributed to alcohol consumption, and this is increasing with time. This figure challenges the widespread perception of alcohol as a harmless social lubricant and builds on several well-conducted studies linking alcohol consumption to cancer risk.

But this isn’t just about the present—it’s also about the future. The report highlights a concerning trend: rising rates of certain cancers among younger adults. It’s a plot twist that researchers like me are still trying to understand, but alcohol consumption is emerging as a potential frontrunner in the list of causes.

Of particular concern is the rising incidence of early-onset colorectal cancer among adults under 50. The report notes a 1.9 percent annual increase between 2011 and 2019.

While the exact causes of this trend are still being investigated, research consistently shows a link between frequent and regular drinking in early and mid-adulthood and a higher risk of colon and rectal cancers later in life. But it’s also important to realize this story isn’t a tragedy.

It’s more of a cautionary tale with the potential for a hopeful ending. Unlike many risk factors for cancer, alcohol consumption is one we can control. Reducing or eliminating alcohol intake can lower the risk, offering a form of empowerment in the face of an often unpredictable disease.

The relationship between alcohol and cancer risk generally follows a dose-response pattern, meaning simply that higher levels of consumption are associated with greater risk. Even light to moderate drinking has been linked to increased risk for some cancers, particularly breast cancer.

Yet it’s crucial to remember that while alcohol increases cancer risk, it doesn’t mean everyone who drinks will develop cancer. Many factors contribute to cancer development.

Damages DNA

The story doesn’t end with these numbers. It extends to the very cells of our bodies, where alcohol’s journey begins. When we drink, our bodies break down alcohol into acetaldehyde, a substance that can damage our DNA, the blueprint of our cells. This means that alcohol can potentially rewrite our DNA and create changes called mutations, which in turn can cause cancer.

The tale grows more complex when we consider the various ways alcohol interacts with our bodies. It can impair nutrient and vitamin absorption, alter hormone levels, and even make it easier for harmful chemicals to penetrate cells in the mouth and throat. It can affect the bacteria in our guts, the so-called microbiome, that we live with and is important for our health and well-being.