How Alcohol Affects Lung Cancer

Medically Reviewed by Michael W. Smith, MD on December 11, 2020
4 min read

Drinking alcohol is strongly linked with cancers all over the body, from the head and neck to the breasts, liver, colon, and rectum. But studies haven’t shown a clear connection between alcohol and lung cancer.

But drinking often goes hand in hand with other cancer-causing habits, like smoking, which is the No. 1 cause of lung cancer. Alcohol also doesn’t mix well with some commonly used cancer meds. So while studies have had scattered results as to a direct cause and effect, experts say it’s still important to understand alcohol’s role in your lung health. And it’s crucial to avoid drinking during and after lung cancer treatment.

“The evidence for [alcohol causing] lung cancer is inconsistent and is considered limited,” says Marji McCullough, a registered dietitian and senior scientific director of epidemiology research for the American Cancer Society. 

Researchers are looking into alcohol’s possible role in causing or speeding the progress of cancers, says Kathy Jung, PhD, who directs the Division of Metabolism and Health Effects at the National Institute on Alcohol Abuse and Alcoholism. Although they haven’t found any clear answers, there’s broad evidence that drinking too much raises inflammation throughout the body as well as in separate tissues.

If the swelling is chronic, or ongoing, it might help set the stage for cancer to form or grow worse, Jung notes. Oxidative stress, which happens when the balance of healthy antioxidants in your cells and tissues is threatened, can further damage your lungs.

It’s also key to consider how alcohol affects habits that are proven to cause lung disease: in particular, smoking.

Drinking and smoking often happen together, McCullough says. “It’s important to tease apart the role of smoking in any studies of alcohol and lung cancer.”

The main message McCullough and the American Cancer Society aim to share is that for lung cancer prevention, it’s best not to smoke. Despite the many screening methods, “there are lots of things that aren’t easily detected,” McCullough says. So in addition to avoiding tobacco, you should also curb your alcohol intake to be safe. 

Some chemotherapy drugs that treat lung cancer are processed in the liver, where alcohol can cause swelling. People who are having chemo are usually advised to limit their drinking, McCullough says.

She notes that treatments are constantly changing, which makes it even more key to stay on top of how new chemo methods affect the body. It’s important to talk to your oncologist or doctor to find out whether drinking is OK, she says.

Alcohol misuse -- heavy daily drinking or binge drinking, which is drinking a lot in a short time -- in general can harm healthy lungs, Jung says. People with alcohol use disorder, defined as problem drinking that’s become severe, are more likely to get lung infections or diseases such as pneumonia, tuberculosis, and other serious respiratory problems.

Alcohol also can hamper healing after lung cancer treatment. Long-term drinking breaks down your immune system’s defenses against infection, as does chemotherapy. Chemo can continue to weaken your immune system for several weeks, and sometimes longer, after treatment. So it’s best to avoid stressing your immune system with alcohol.

The American Cancer Society says that for general cancer prevention, it’s best not to drink alcohol. But to be realistic, “we recommend women not have more than one drink a day and men not more than two,” McCullough says. This advice may also change over time. “Evidence is always growing, and guidelines evolve with the evidence.”

There’s some debate about whether alcohol’s effects differ by the type of drink. “Beverage alcohol, or ethyl alcohol, is the same across products,” Jung says. “What is most important for health is the number of servings rather than the type of beverage.”

A standard U.S. serving of alcohol is defined as 14 grams (0.6 fluid ounces) of pure ethyl alcohol. It’s the amount in a 12-ounce beer or seltzer with 5 percent alcohol; a 5-ounce glass of wine with 12% alcohol; or 1.5 ounces of distilled spirits, or liquor, with 40% (80-proof) alcohol.

People who shouldn’t drink at all include women who are or might be pregnant; people under age 21; people who are recovering from alcohol use disorder; and those taking meds that might interact badly with alcohol. If you’ll be driving or otherwise doing something that relies on skill, coordination, and/or alertness, don’t pick up an alcoholic drink.

Jung also warns that even moderate drinking can harm your health, “such as an increase in the risk of breast cancer for women and increase in the risk of falls for older drinkers.”