- Drinking alcohol in excess potentially escalates the risk of heart disease and cancer.
- Many study findings suggest that the main factor that influences risk is actually the amount of alcohol that is consumed.
- In general, it is recommended that people in good health consume moderate amounts of alcohol—if any—and maintain a healthy diet and exercise routine.
A growing body of research points to a connection between alcohol consumption and elevated cancer risk. Studies from the American Institute for Cancer Research have found that having even less than one drink a day, of any kind of alcohol, increases the risk of several types of cancer, including breast, colorectal, esophageal, liver, stomach, mouth, throat, and voice box (larynx). While any amount of alcohol can raise one’s risk of developing these cancers, the more one drinks, the higher the risk.
Because of this, the American Cancer Society Guideline for Diet and Physical Activity for Cancer Prevention recommendation is that people should avoid alcohol.
Have these findings prompted people to drink less?
Overall, the percentage of Americans who say they occasionally drink alcohol has stayed between 60 and 70% since the late 1930s, without any noticeable decline in recent years, according to polling by the Gallup organization.
If findings of alcohol’s impact on cancer risk have yet to deter many people from drinking, it may be because most people aren’t aware of them. According to the American Cancer Society, less than half of the American public recognizes that alcohol is a carcinogen (cancer-causing substance).
What advice do nutritionists offer about drinking alcohol?
“My general advice is largely to avoid alcohol – to save drinking for special occasions like weddings or graduations,” says Annette Goldberg, MS, RD, a senior clinical nutritionist at Dana-Farber. “Because of social expectations, it can be a challenge for people to say no to alcohol, but, recognizing that, people also need to be aware of the risks associated with drinking.”
She notes that the growing number and variety of non-alcoholic beverages can be an option for people who want to stop or cut back on drinking.
What of the longstanding guidelines of two drinks a day for men and one for women? That recommendation “was intended to prevent people from becoming alcoholics,” psychologist Tim Stockwell, PhD, of the University of Victoria noted in a recent article in Scientific American.
“It wasn’t so much how you protect your body from cancer, liver disease, or losing a few months or even years of life expectancy,” he said.
The risks of alcohol consumption are so substantial that the World Health Organization recently declared any amount of alcohol to be dangerous.
“There is no safe amount that does not affect health,” the group stated.
Doesn’t alcohol have cardiovascular benefits?
Evidence of such benefits – that drinking red wine, for example, protects against heart disease – was always tenuous and has been weakened further by recent research. The supposed heart-protective effects of red wine were based on findings that moderate drinkers had better cardiovascular health than non-drinkers and heavy drinkers. But those studies categorized people who had stopped drinking because of addiction or illness as non-drinkers. As a result, the non-drinking group looked relatively unhealthy compared to others.
How does alcohol raise cancer risk?
The physical and biological links between alcohol use can cancer risk aren’t well understood, but several processes are likely at work.
According to the American Cancer Society, alcohol can:
- Act as an irritant, especially in the mouth and throat. Cells damaged by alcohol will try to repair themselves, potentially accruing DNA changes that can lead to cancer. Notably, nearly all the cancers associated with alcohol consumption involve tissues that have contact with alcohol itself or its byproducts.
- Be converted into acetaldehyde, a chemical that can spur DNA damage and has been shown to cause cancer in lab animals.
- Produce oxidative stress in cells, overwhelming their ability to detoxify reactive oxygen molecules within them. The resulting intracellular damage might increase the risk of cancer.
- Damage the liver, leading to inflammation and scarring. As liver cells make repairs, they may acquire errors in their DNA that set the stage for cancer.
- Help other harmful chemicals, such as those in tobacco, enter cells lining the upper digestive tract.
- Reduce the body’s ability to absorb nutrients like folate that are needed to stay healthy.
- Raise levels of estrogen, a hormone involved in the growth and development of breast tissues, potentially affecting the risk of breast cancer. (About 15% of breast cancers are linked to alcohol.)
- Add extra calories to the diet, contributing to weight gain – a known cancer risk.
Does alcohol use pose an additional risk during cancer treatment?
Yes. Even small amounts of alcohol can irritate mouth sores caused by some cancer treatments, including chemotherapy. Alcohol can also interact with certain cancer drugs, potentially raising the risk of harmful side effects. Alcohol use while receiving cancer therapy can be especially taxing on the liver, burdening it with removing the toxic compounds in alcohol as well as in cancer drugs.