Alcohol Use and Cancer

Most people know that heavy alcohol use can cause health problems. But many people may not be aware that alcohol use can increase their risk of cancer.

Types of cancer linked to alcohol use

Alcohol is a known cause of cancers of the:

• Mouth
• Throat (pharynx)
• Voice box (larynx)
• Esophagus
• Liver
• Colon and rectum
• Breast

Alcohol may also increase the risk of cancer of the pancreas.

For each of these cancers, the risk increases with the amount of alcohol consumed.

Cancers of the mouth, throat, voice box, and esophagus: Alcohol use clearly raises the risk of these cancers. Drinking and smoking together raises the risk of these cancers far more than the effects of either drinking or smoking alone. This might be because alcohol can act as a solvent, helping harmful chemicals in tobacco to get into the cells lining the digestive tract. Alcohol may also slow down these cells' ability to repair DNA damage caused by chemicals in tobacco.

Liver cancer: Long-term alcohol use has been linked to an increased risk of liver cancer. Regular, heavy alcohol use can damage the liver, leading to inflammation. This, in turn, may raise the risk of liver cancer.

Colon and rectal cancer: Alcohol use has been linked with a higher risk of cancers of the colon and rectum. The evidence for such a link is generally stronger in men than in women, although studies have found the link in both sexes.

Breast cancer: Even a few drinks a week is linked with an increased risk of breast cancer in women. This risk may be especially high in women who do not get enough folate (a B vitamin) in their diet or through supplements. Alcohol can affect estrogen levels in the body, which may explain some of the increased risk. Drinking less alcohol may be an important way for many women to lower their risk of breast cancer.

Does the type of drink matter?

Ethanol is the type of alcohol found in alcoholic drinks, whether they are beers, wines, or liquors (distilled spirits). These drinks contain different percentages of ethanol, but in general a standard size drink of any type — 12 ounces of beer, 5 ounces of wine, or 1.5 ounces of 80-proof liquor — contains about the same amount of ethanol (about half an ounce). Of course, larger or 'stronger' drinks may contain more ethanol than this.

Overall, the amount of alcohol consumed over time, not the type of alcoholic beverage, seems to be the most important factor in raising cancer risk. Most evidence suggests that it is the ethanol itself that is responsible for the increased risk, not other things in the drink.

How does alcohol raise cancer risk?

The exact way in which alcohol affects cancer risk isn't completely understood. In fact, there may be several different ways in which it raises risk, and this may depend on the type of cancer.

Damage to body tissues: Alcohol may act as an irritant, especially in the mouth and throat. Cells that are damaged may try to repair themselves, which may lead to DNA changes in the cells that can be a step toward cancer.

In the colon and rectum, bacteria can convert alcohol into large amounts of acetaldehyde, a chemical that has been shown to cause cancer in lab animals.

Alcohol and its byproducts can also directly damage the liver, leading to inflammation and scarring. As liver cells try to repair the damage, they may acquire mistakes in their DNA.

Effects on other harmful chemicals: Alcohol may act as a solvent, helping other harmful chemicals, such as those found in tobacco smoke, to enter the cells lining the upper digestive tract more easily. This may help explain why the combination of smoking and drinking is much more likely to cause cancers in the mouth or throat than either smoking or drinking alone. In other cases, alcohol may slow the body's ability to break down and get rid of some harmful chemicals.

Lower levels of folate or other nutrients: Folate is a vitamin that cells in the body need to stay healthy. Alcohol use may lower the body's ability to absorb folate from foods. This problem can be compounded in heavy drinkers, who often do not get enough nutrients such as folate in their diet. Low folate levels may play a role in the risk of breast and colorectal cancers.

Effects on estrogen or other hormones: Alcohol may raise body levels of estrogen, a hormone important in the growth and development of breast tissue. This may have an effect on a woman's risk of breast cancer.

Effects on body weight: Too much alcohol can add extra calories to the diet, which can contribute to weight gain in some people. Being overweight or obese is known to increase the risks of many types of cancer.

Along with these mechanisms, alcohol may contribute to cancer in other, as of yet unknown, ways.

Are there other long-term health effects from drinking alcohol?

Most people are aware of the potential short-term effects of drinking alcohol, such as its effects on mood, concentration, judgment, and coordination. Alcohol can have longer-term health effects as well. These effects can vary a great deal from person to person.

For some people, alcohol is addictive. Drinking may become heavier over time, leading to serious health and social problems. Heavy drinkers who stop drinking abruptly can have physical withdrawal symptoms such as body tremors, changes in mental function, and seizures. In some cases these can be life-threatening. This does not mean that heavy drinkers should not stop drinking. It does mean that heavy drinkers should talk with their health care team about the safest way to stop drinking.

Over time, the major effects of heavy alcohol use on the liver can include inflammation (hepatitis) and heavy scarring (cirrhosis). This can lead to liver failure. Heavy alcohol use can also damage other organs, such as the pancreas and the brain, and can raise blood pressure.

Alcohol use in pregnant women, especially heavy drinking, can affect the fetus, and may lead to birth defects or other problems.

On the other hand, low to moderate alcohol use has been linked with a lower risk of heart disease. Low to moderate use is usually defined as 1 or 2 drinks a day for a man or 1 drink a day for a woman. The potential benefit of lowering heart disease risk has to be weighed against the other possible health risks for each person. It's also important to know that the risk of heart disease and stroke actually increases with heavy drinking.

What does the American Cancer Society recommend?

As part of its guidelines on nutrition and physical activity for cancer prevention, the American Cancer Society recommends that people who drink alcohol limit their intake to no more than 2 drinks per day for men and 1 drink a day for women. The recommended limit is lower for women because of their smaller body size and because their bodies tend to break down alcohol more slowly. These daily limits do not mean you can drink larger amounts on fewer days of the week, since this can lead to health, social, and other problems.

While alcohol use has been linked to several types of cancer and other health risks, this is complicated by the fact that low to moderate alcohol intake has been linked with a lower risk of heart disease. Still, reducing the risk of heart disease is not a compelling reason for adults who currently do not drink alcohol to start. There are many ways of reducing heart disease risk, including avoiding smoking, eating a diet low in saturated and trans fats, staying at a healthy weight, staying physically active, and controlling blood pressure and cholesterol.

Some groups of people should not drink alcoholic beverages at all. These include:

• Children and teens
• People who cannot limit their drinking or who have a family history of alcoholism
• Women who are or may become pregnant
• People who plan to drive or operate machinery
• People who take part in other activities that require attention, skill, or coordination
• People taking prescription or over-the-counter medicines that interact with alcohol

Alcohol use during and after cancer treatment

As noted above, many studies have found a link between alcohol intake and the risk of developing certain cancers. But it is not clear whether alcohol use after treatment might increase the risk of these cancers coming back (recurring). In theory, it is possible that alcohol use might raise the risk of recurrence. For example, alcohol intake can increase the levels of estrogens in the body, which might increase the risk for recurrence of breast cancer. But there is no strong evidence from studies to support this.

In people who have already been diagnosed with cancer, alcohol intake could also affect the risk for developing a new cancer.

There are some cases in which alcohol should clearly be avoided during cancer treatment. For example, alcohol – even in very small amounts – can irritate mouth sores caused by some cancer treatments, and can even make them worse. Alcohol can also interact with some drugs used during cancer treatment, increasing the risk of harmful side effects.

But for people who have completed cancer treatment, the effects of alcohol on cancer recurrence risk are largely unknown. It's important to discuss this with your doctor. Factors that may be important include the type of cancer, your risk of recurrence, the treatment(s) you've had, your overall health, and the other possible risks and benefits of drinking.

To learn more

More information from your American Cancer Society

The following information may also be helpful to you. These materials may be ordered from our toll-free number, 1-800-227-2345.

American Cancer Society Guidelines on Nutrition and Physical Activity for Cancer Prevention

Nutrition and Physical Activity During and After Cancer Treatment: Answers to Common Questions

National organizations and Web sites*

Along with the American Cancer Society, other sources of patient information and support include:

For more on the link between alcohol and cancer

American Institute for Cancer Research (AICR)
Toll-free number: 1-800-843-8114
Web site: www.aicr.org

Helps people make informed choices about body weight, physical activity, and diet (including alcohol use) that may reduce their risk of cancer.

Centers for Disease Control and Prevention (CDC)
Toll-free number: 1-800-232-4636 (1-800-CDC-INFO)
Home page: www.cdc.gov
Alcohol and public health page: www.cdc.gov/alcohol

Has a wide variety of fact sheets and other information about the health problems linked to alcohol use.

For help with alcohol problems

Alcoholics Anonymous (AA)
Phone number: 1-212-870-3400
Web site: www.aa.org

Makes referrals to local AA groups and provides informational materials on the AA
program. Many cities and towns also have a local AA office listed in the phone book.

Al-Anon/Alateen
Toll-free number: 1-888-4AL-ANON (1-888-425-2666)
Web site: www.al-anon.alateen.org

Makes referrals to local Al-Anon groups, which are support groups for spouses and other significant adults in an alcoholic person's life. Also makes referrals to Alateen groups, which offer support to children of alcoholics.

National Council on Alcoholism and Drug Dependence (NCADD)
Toll-free number: 1-800-NCA-CALL (1-800-622-2255)
Web site: www.ncadd.org

Provides telephone numbers of local NCADD affiliates (who can provide information on local treatment resources) and educational materials on alcoholism.

National Institute on Alcohol Abuse and Alcoholism (NIAAA)
Phone number: 1-301-443-3860
Web site: www.niaaa.nih.gov

Publications available from NIAAA feature information on a wide variety of topics, including fetal alcohol syndrome, the dangers of mixing alcohol with medications, family history of alcoholism, and preventing underage drinking.

Substance Abuse and Mental Health Services Administration (SAMHSA)
Substance Abuse Treatment Facility Locator
Toll-free number: 1-800-662-HELP (1-800-662-4357)
Web site: www.findtreatment.samhsa.gov

Provides alcohol and drug information and treatment referral assistance. (Part of the US Department of Health and Human Services.)

*Inclusion on this list does not imply endorsement by the American Cancer Society.

References

American Cancer Society. Cancer Facts & Figures 2012. Atlanta, Ga: American Cancer Society; 2012.

Allen NE, Beral V, Casabonne D, et al. Moderate alcohol intake and cancer incidence in women. J Natl Cancer Inst. 2009;101:296-305.

Centers for Disease Control & Prevention (CDC). Alcohol and Public Health: Frequently Asked Questions. 2011. Accessed at www.cdc.gov/alcohol/faqs.htm on January 12, 2012.

Chen WY, Rosner B, Hankinson SE, Colditz GA, Willett WC. Moderate alcohol consumption during adult life, drinking patterns, and breast cancer risk. JAMA. 2011;306:1884-1890.

Doyle C, Kushi LH, Byers T, et al. Nutrition and physical activity during and after cancer treatment: An American Cancer Society guide for informed choices. CA Cancer J Clin. 2006;56:323-353.

International Agency for Research on Cancer. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. Volume 96: Alcohol Consumption and Ethyl Carbamate. 2010. Accessed at http://monographs.iarc.fr/ENG/Monographs/vol96/mono96.pdf on January 12, 2012.

Kushi LH, Doyle C, McCullough M, et al. American Cancer Society guidelines on nutrition and physical activity for cancer prevention: Reducing the risk of cancer with healthy food choices and physical activity. CA Cancer J Clin. 2012;62:30-67.

Lew JQ, Freedman ND, Leitzmann MF, et al. Alcohol and risk of breast cancer by histologic type and hormone receptor status in postmenopausal women: The NIH-AARP Diet and Health Study. Am J Epidemiol. 2009;170:308-317.

World Cancer Research Fund / American Institute for Cancer Research. Food, Nutrition, Physical Activity, and the Prevention of Cancer: A Global Perspective. Washington DC: AICR, 2007.