Cancer Research UK : Alcohol and cancer: the evidence

Alcohol and cancer: the evidence

Evidence linking alcohol to cancer.

This page contains information about the links between alcohol and cancer. Click on the links below to read about specific topics.

Alcohol and cancer
Mouth and foodpipe cancer
Liver cancer
Breast cancer
Drinking while pregnant
Smoking and drinking
Why does alcohol cause cancer?
Safe limits
Benefits of cutting down
Red wine and cancer

You can find out more about the evidence behind other health topics in our other How do we know? pages.

Alcohol is one of the most well established causes of cancer

International health organisations like the World Health Organisation agree that alcohol can cause a range of cancers.1-4 This is based on the consistent results of many different studies all around the world.4 This page will tell you about why we think alcohol is a risk factor for cancer.

The Oxford Textbook of Medicine estimates that 6% of cancer deaths in the UK are caused by alcohol. And all of these deaths could be avoided.5

Alcohol increases the risk of mouth and oesophageal (foodpipe) cancers

Aside from smoking, alcohol is the most important cause of mouth and foodpipe cancers.

One review of many studies found that people who drink 6 units a day have triple the risk of mouth cancer and double the risk of oesophageal cancer, compared to non-drinkers.6 That’s the same as two pints of premium lager or three standard glasses of wine.

The International Agency for Cancer Research says that heavy drinking increases the risks of these cancers by 5 to 10 times.4 But even light drinking (just three units a day) can increase the risk of mouth cancer.6

Alcohol increases the risk of liver cancer

Alcohol is one of the main risk factors for liver cancer.7 Heavy drinking can lead to cirrhosis, a condition where the liver is repeatedly damaged and scar tissue builds up. Cirrhosis increases the risk of liver cancer.

And the risks of liver cancer are even greater if a person is infected with the hepatitis B or C viruses. One in five people with these viruses develop cirrhosis and liver cancer. People with these infections should avoid alcohol, as even small amounts could damage their livers.8

Alcohol increases the risk of breast cancer

Even small amounts of alcohol can increase your risk of breast cancer. Several studies have found that every alcohol unit drunk a day increases the risk of breast cancer risk by about 7-11%.9-12

A Cancer Research UK-funded study estimated that alcohol causes about 2,000 breast cancer cases every year in the UK alone.11

There is unlikely to be a safe level of alcohol which doesn’t increase the risk of breast cancer. Some studies have found that drinking just one unit a day can increase a woman’s chances of developing breast cancer.13

Alcohol increases the risk of bowel cancer

Studies have recently shown that alcohol can increase the risk of bowel cancer and even small amounts can have an effect. The EPIC study found that for every 2 units a person drinks each day (less than a pint of premium lager) their risk of bowel cancer goes up by 8%.14

Smoking and drinking together increases risk even more

Tobacco also causes mouth, oesophageal and liver cancers but scientists have found the effects of alcohol and tobacco together are much worse.

One study found that the risk of liver cancer was ten times greater in people who smoked tobacco and drank alcohol.15 And a Spanish team found that people who smoke and drink heavily could increase their risk of oesophageal cancer by up to 100 times.2,16 This problem is made even worse because heavy drinkers and smokers often have unhealthy diets.17

Drinking alcohol during pregnancy may increase the cancer risks of your children

An American study found that women who drank alcohol during pregnancy increased the risk of leukaemia in their children.18 Two larger studies are now under way to confirm this result. Until their results are available, pregnant women are advised to stop drinking alcohol.

Alcohol could cause cancer in many ways

At the moment, we are not entirely sure how alcohol causes cancer but there are several ideas.

The strongest one is that in the body, alcohol is converted into a chemical called acetaldehyde. Acetaldehyde is the chemical that causes hangovers, but it can also cause cancer by damaging our DNA and preventing it from being repaired. People who smoke and drink heavily have very high levels of acetaldehyde in their saliva 19.

Here are some other theories:

Alcohol can increase the level of hormones such as oestrogen in the body. Unusually high levels of oestrogen could cause breast cancer.20
Alcohol can cause cirrhosis of the liver by repeatedly damaging the liver’s cells.6 This in turn can cause liver cancer.
Alcohol makes it easier for dangerous chemicals to be absorbed in the mouth or throat. This includes the chemicals in tobacco that can cause cancer.2
Alcohol reduces the amount of folate in our blood.21 Folate is a B vitamin that our cells need to create new DNA correctly. It prevents changes to our DNA that could lead to cancer.

If you drink alcohol, stick to safe limits

The more alcohol that someone drinks, the more their cancer risk increases. But even very small amounts of alcohol, as little as one drink a day, can increase cancer risk 22,23. A team of Italian scientists analysed over 200 studies on alcohol and cancer. They were unable to find any lower daily limit of drinking alcohol where cancer risk was not increased.24

But drinking small amounts of alcohol also reduces the risk of heart disease, although this mainly applies to men over 40 and post-menopausal women.25

Because of this many sources including the World Health Organisation and the European Code Against Cancer have suggested that women should drink less than two units a day, and men should drink less than three a day.26 While these levels may increase the risk of cancer, the actual effects are likely to be small.

Cutting down on alcohol can reduce your risk of cancer

The risk of alcohol-related cancers increases the more you drink. So by cutting down on what you drink, you can reduce your risk of several cancers.

If you are a heavy drinker, it is not too late to start cutting down. UK scientists recently showed that oesophageal cancer risk drops dramatically in heavy drinkers who stop drinking.27

Red wine does not protect against cancer

One small but widely reported study found that men who drank 4-7 glasses of red wine per week halved their risk of prostate cancer.28 Red wine contains a chemical called resveratrol, which may have some anti-cancer effects. However, two much larger studies have since found that red wine does not affect a man’s risk of prostate cancer.29,30 So far, studies have shown that all types of alcohol, including beer, wine and spirits, can increase the risk of cancer.2,31

References

WHO/FAO, Joint WHO/FAO Expert Consultation on Diet, Nutrition and the Prevention of Chronic Diseases, in WHO Technical Report Series. 2003, WHO: Geneva. p. 95-104.Link
Boyle, P., et al., European Code Against Cancer and scientific justification: third version (2003). Ann Oncol, 2003. 14(7): p. 973-1005.PubMed
WCRF and AICR, Food, nutrition and the prevention of cancer: a global perspective. 1997, American Institute for Cancer Research: Washington. p. 37-145.Link
IARC, World Cancer Report, ed. B. Stewart and P. Kleihues. 2003, Lyon: IARCPress.Link
Doll, R. and R. Peto, Epidemiology of Cancer. Oxford Textbook of Medicine, ed. D. Warrell, et al. 2003, Oxford: OUP.Link
Corrao, G., et al., A meta-analysis of alcohol consumption and the risk of 15 diseases. Prev Med, 2004. 38(5): p. 613-9.PubMed
Stickel, F., et al., Cocarcinogenic effects of alcohol in hepatocarcinogenesis. Gut, 2002. 51: p. 132-139.PubMed
Schiff, E. and N. Ozden, Hepatitis C and alcohol. Alcohol Res Health, 2003. 27: p. 232-239.PubMed
Smith-Warner, S., et al., Alcohol and breast cancer in women: a pooled analysis of cohort studies. JAMA, 1998. 279: p. 535-40.PubMed
Key, J., et al., Meta-analysis of Studies of Alcohol and Breast Cancer with Consideration of the Methodological Issues. Cancer Causes Control, 2006. 17(6): p. 759-770.PubMed
Hamajima, N., et al., Alcohol, tobacco and breast cancer--collaborative reanalysis of individual data from 53 epidemiological studies, including 58,515 women with breast cancer and 95,067 women without the disease. Br J Cancer, 2002. 87(11): p. 1234-45.PubMed
Zhang, S.M., et al., Alcohol consumption and breast cancer risk in the Women's Health Study. Am J Epidemiol, 2007. 165(6): p. 667-76.PubMed
Longnecker, M., Alcoholic beverage consumption in relation to risk of breast cancer: meta-analysis and review. Cancer Causes Control, 1994. 5: p. 73-82.PubMed
Ferrari, P., et al., Lifetime and baseline alcohol intake and risk of colon and rectal cancers in the European prospective investigation into cancer and nutrition (EPIC). Int J Cancer, 2007.PubMed
Kuper, H., et al., Tobacco smoking, alcohol consumption and their interaction in the causation of hepatocellular carcinoma. Int J Cancer, 2000. 85: p. 498-502.PubMed
Castellsague, X., et al., Independent and joint effects of tobacco smoking and alcohol drinking on the risk of esophageal cancer in men and women. Int J Cancer, 1999. 82: p. 657-64.PubMed
Key, T., et al., The effect of diet on risk of cancer. Lancet, 2002. 360: p. 861-868.PubMed
Shu, X., et al., Parental alcohol consumption, cigarette smoking, and risk of infant leukemia: a Children's Cancer Group study. J Natl Cancer Inst, 1996. 88: p. 24-31.PubMed
Salaspuro, V. and M. Salaspuro, Synergistic effect of alcohol drinking and smoking on in vivo acetaldehyde concentration in saliva. Int J Cancer, 2004. 111: p. 480-483.PubMed
Onland-Moret, N., et al., Alcohol and Endogenous Sex Steroid Levels in Postmenopausal Women: a cross-sectional study. J Clin Endocrinol Metab, 2004. Epub ahead of print.PubMed
Giovannucci, E., Epidemiologic studies of folate and colorectal neoplasia: a review. J Nutr, 2002. 132(8 Suppl): p. 2350S-2355S.PubMed
Thun, M., et al., Alcohol consumption and mortality among middle-aged and elderly U.S. adults. N Engl J Med, 1997. 337: p. 1705-1714.PubMed
Maserejian, N.N., et al., Prospective study of alcohol consumption and risk of oral premalignant lesions in men. Cancer Epidemiol Biomarkers Prev, 2006. 15(4): p. 774-81.PubMed
Bagnardi, V., et al., Alcohol consumption and the risk of cancer: a meta-analysis. Alcohol Res Health, 2001. 25: p. 263-70.PubMed
Doll, R., Mortality in relation to smoking: 40 years' observation on male British doctors. BMJ, 1994. 309: p. 901-911.PubMed
WHO, FAO/WHO consultation on the health implications of acrylamide in food: summary report. 2002, WHO: Geneva. p. 1-12.Link
Cheng, K., et al., Stopping drinking and risk of oesophageal cancer. BMJ, 1995. 310: p. 1094-7.PubMed
Schoonen, W., et al., Alcohol consumption and risk of prostate cancer in middle-aged men. Int J Cancer, 2005. 113: p. 133-40.PubMed
Velicer, C.M., A. Kristal, and E. White, Alcohol use and the risk of prostate cancer: results from the VITAL cohort study. Nutr Cancer, 2006. 56(1): p. 50-6.PubMed
Sutcliffe, S., et al., A prospective cohort study of red wine consumption and risk of prostate cancer. Int J Cancer, 2007.PubMed
Blot, W., Alcohol and cancer. Cancer Research, 1992. (suppl) 52: p. 2119-2123.PubMed