According to a report by the National Cancer Institute, heavy or regular alcohol consumption increases the risk of developing cancers of the oral cavity (excluding the lips), pharynx (throat), larynx (voice box), esophagus, liver, breast, colon, and rectum.
Based on extensive reviews of research studies, there is a strong scientific consensus of an association between alcohol drinking and several types of cancer. In its Report on Carcinogens, the National Toxicology Program of the US Department of Health and Human Services lists consumption of alcoholic beverages as a known human carcinogen. The research evidence indicates that the more alcohol a person drinks—particularly the more alcohol a person drinks regularly over time—the higher his or her risk of developing an alcohol-associated cancer. Based on data from 2009, an estimated 3.5 percent of all cancer deaths in the United States (about 19,500 deaths) were alcohol related (3).
Clear patterns have emerged between alcohol consumption and the development of the following types of cancer:
- Head and neck cancer: People who consume 50 or more grams of alcohol per day (approximately 3.5 or more drinks per day) have at least a two to three times greater risk of developing these cancers than nondrinkers.
- Esophageal cancer
- Liver cancer
- Breast cancer: More than 100 studies have looked at the association between alcohol consumption and the risk of breast cancer in women. These studies have consistently found an increased risk of breast cancer associated with increasing alcohol intake.
- Colorectal cancer: People who regularly drank more than 3.5 drinks per day had 1.5 times the risk of developing colorectal cancer as nondrinkers or occasional drinkers
How does alcohol increase the risk of cancer?
Researchers have identified multiple ways that alcohol in the body may increase the risk of cancer:
- changing the ethanol in alcoholic drinks to acetaldehyde, a toxic chemical and a probable human carcinogen.
- impairing the body’s ability to break down and absorb a variety of nutrients, including essential vitamins,
- increasing blood levels of estrogen, a sex hormone linked to the risk of breast cancer
Alcoholic beverages may also contain a variety of contaminants that are introduced during fermentation and production, such as asbestos fibers, phenols, and hydrocarbons.
How does the combination of alcohol and tobacco affect cancer risk?
Epidemiologic research shows that people who use both alcohol and tobacco have much greater risks of developing mouth and throat cancers than people who use either alcohol or tobacco alone.
The full version of this article, including references and additional information about the studies can be downloaded here.