Alcohol and Cancer: A Mixed Picture, but Harmful Overall

Alcohol use is responsible for an estimated 3.5% of cancers in the United States, but affects the risk of developing some cancers more than others.

Alcohol use is responsible for an estimated 3.5% of cancers in the United States, but affects the risk of developing some cancers more than others.

The risk of developing cancer may be related to alcohol intake, according to a Bagnardi and colleagues, who conducted a multicountry meta-analysis of the effect of alcohol on the risk of developing more than 20 types of cancer. To complete the meta-analysis, investigators compiled data from 572 studies, including nearly 500,000 cases of cancer, to evaluate the dose of alcohol as related to cancer risk.1

Investigators compared cancer risk across several body sites for light drinkers (12.5 g or less of alcohol consumption daily), moderate drinkers (50 g or less of alcohol consumption daily), and heavy drinkers (50 g or more of alcohol consumption daily), and compared each group with a reference population of nondrinkers. Investigators limited subgroup analyses to cancer sites that had more than 10 studies conducted, which reduced the likelihood of drawing conclusions based on sparse data.1

Oral cavity and pharyngeal cancer1:

  • Light drinking increased the risk of oral cavity and pharyngeal cancer by 13% (RR: 1.13 [95% CI 1.00-1.26])
  • Moderate drinking increased the risk of oral cavity and pharyngeal cancer by 83% (RR: 1.83 [95% CI 1.62-2.07])
  • Heavy drinking increased the risk of oral cavity and pharyngeal cancer by 413% (RR: 5.13 [95% CI 4.31—6.10])

Esophageal cancer1:

  • Light drinking increased the risk of esophageal cancer by 26% (RR: 1.26 [95% CI 1.06-1.50])
  • Moderate drinking increased the risk of esophageal cancer by 123% (RR: 2.23 [95% CI 1.87-2.65])
  • Heavy drinking increased the risk of esophageal cancer by 395% (RR: 4.95 [95% CI 3.86-6.34])

Breast cancer (limited to females in this analysis)1:

  • Light drinking increased the risk of breast cancer by 4% (RR: 1.04 [95% CI 1.01-1.07])
  • Moderate drinking increased the risk of breast cancer by 23% (RR: 1.23 [95% CI 1.19-1.28])
  • Heavy drinking increased the risk of breast cancer by 61% (RR: 1.61 [95% CI 1.33-1.94])

Colorectal cancer1:

  • Moderate drinking increased the risk of colorectal cancer by 17% (RR: 1.17 [95% CI 1.11-1.24])
  • Heavy drinking increased the risk of colorectal cancer by 44% (RR: 1.44 [95% CI 1.25-1.65])

Laryngeal cancer1:

  • Moderate drinking increased the risk of laryngeal cancer by 44% (RR: 1.44 [95% CI 1.25-1.66])
  • Heavy drinking increased the risk of laryngeal cancer by 165% (RR: 2.65 [95% CI 2.19-3.19])

However, alcohol did not significantly increase the risk of1:

  • Adenocarcinoma of the esophagus or gastric cardia
  • Cancers of the small intestine
  • Cervical cancers
  • Endometrial cancers
  • Ovarian cancer
  • Bladder cancer
  • Brain cancer

In addition, alcohol may have a preventive effect in some cancers, such as lymphomas, kidney cancers, and thyroid cancers.1

Alcohol significantly reduced the risk of developing Hodgkin’s lymphoma1:

  • Light drinking reduced the risk of Hodgkin’s lymphoma by 26% (RR: 0.73 [95% CI 0.59-0.89])
  • Moderate drinking reduced the risk of Hodgkin’s lymphoma by 26% (RR: 0.73 [95% CI 0.60-0.87])
  • Heavy drinking reduced the risk of Hodgkin’s lymphoma by 37% (RR: 0.63 [95% CI 0.41-0.97])

Alcohol also significantly reduced the risk of developing non-Hodgkin’s lymphoma1:

  • Light drinking reduced the risk of non-Hodgkin’s lymphoma by 12% (RR: 0.88 [95% CI 0.80-0.97])
  • Moderate drinking reduced the risk of non-Hodgkin’s lymphoma by 13% (RR: 0.87 [95% CI 0.81-0.95])
  • Heavy drinking reduced the risk of non-Hodgkin’s lymphoma by 25% (RR: 0.75 [95% CI 0.64-0.88])

Some investigators believe that the apparent relationship between a reduced risk of lymphoma and heavier alcohol use may be due to patients reducing alcohol consumption or eliminating it altogether when they develop early lymphoma symptoms. In lymphoma, alcohol may not have a true preventive effect.1-3

Light to moderate alcohol consumption significantly reduced the risk of developing kidney cancer1:

  • Light drinking reduced the risk of kidney cancer by 8% (RR: 0.92 [95% CI 0.86-0.99])
  • Moderate drinking reduced the risk of kidney cancer by 21% (RR: 0.79 [95% CI 0.72-0.86])

Light to moderate alcohol consumption significantly also reduced the risk of developing thyroid cancer1:

  • Light drinking reduced the risk of thyroid cancer by 19% (RR: 0.81 [95% CI 0.74-0.88])
  • Moderate drinking reduced the risk of thyroid cancer by 19% (RR: 0.81 [95% CI 0.71-0.94])

The mechanism by which light to moderate alcohol consumption reduces the risk of kidney cancer and thyroid cancer is unknown.1

Alcohol is responsible for 2.5 million deaths yearly and exacerbates liver cirrhosis, epilepsy, road accidents, and violence.4 Alcohol use also increases the burden of new cancer diagnoses. In 2009, alcohol consumption was responsible for approximately 3.5% of cancer cases in the United States, predominantly cancers of the oral cavity, pharynx, liver, larynx, and esophagus.5

Considering recent evidence that alcohol consumption may not reduce cardiovascular disease risk among patients who experience flushing after drinking alcohol,6 as well as the high burden of alcohol-related disease across the globe,5 for many people cutting down on alcohol intake may be a positive change to undertake over the coming year.

References:

  • Bagnardi V, Rota M, Botteri E, et al. Alcohol consumption and site-specific cancer risk: a comprehensive dose-response meta-analysis [published online November 25, 2014]. Br J Cancer.
  • Bryant AJ, Newman JH. Alcohol intolerance associated with Hodgkin lymphoma. CMAJ. 2013;185(8):E353.
  • Brewin TB. Alcohol intolerance in neoplastic disease. Br Med J. 1966;2(5511):437-441.
  • World Health Organization. Global status report on alcohol and health. http://www.who.int/substance_abuse/publications/global_alcohol_report/msbgsruprofiles.pdf. Accessed December 2014.
  • Rehm J, Mathers C, Popova S, Thavorncharoensap M, Teerawattananon Y, Patra J. Global burden of disease and injury and economic cost attributable to alcohol use and alcohol-use disorders. Lancet. 2009;373(9682):2223-2233.
  • Suh HS, Kim JS, Kim SS, Jung JG, Yoon SJ, Ahn JB. Influence of the flushing response in the relationship between alcohol consumption and cardiovascular disease risk. Korean J Fam Med. 2014;35(6):295-302.