Author: Charles Frank

Does Drinking Alcohol Cause Cancer? Learn About the Risks Memorial Sloan Kettering Cancer Center

Another study published in 2021 showed that nearly 70% of people did not even know that alcohol was a cancer risk factor. Another enzyme, called aldehyde dehydrogenase 2 (ALDH2), metabolizes toxic acetaldehyde to nontoxic substances. Some people, particularly those of East Asian descent, carry a variant of the gene for ALDH2 that encodes a defective form of the enzyme. In people who produce the defective enzyme, acetaldehyde builds up when they drink alcohol. The study also found that people who believed drinking alcohol increased the risk of heart disease were more aware of the alcohol–cancer risk than those who were unsure or believed drinking lowered the effect on heart risk.

Dr. Klein noted, “[In] less than half a century, we’ve seen major changes in the way people think about tobacco.” More cancers could be prevented, she says, if people fully understood the risks of alcohol. Understanding these risks would lead to more fully informed decisions about alcohol use among individuals and families, including cancer survivors and those with a family cancer history. As with most questions related to a specific individual’s cancer treatment, it is best for patients to check with their health care team about whether it is safe to drink alcohol during or immediately following chemotherapy treatment. The doctors and nurses administering the treatment will be able to give specific advice about whether it is safe to consume alcohol while undergoing specific cancer treatments. Many individuals of East Asian descent carry a version of the gene for ADH that codes for a “superactive” form of the enzyme.

For female breast cancer, the meta-analysis described here confirms the existence of a strong dose-risk relationship between alcohol consumption level and breast cancer risk. It is possible, however, that for breast cancer and other types of cancer related to disturbances in female hormone levels, alcohol may act by altering the metabolism and blood levels of female hormones, such as estrogen (Longnecker 1994). Moreover, a recent study suggests that the association may be limited to women with a family history of breast cancer (Vachon et al. 2001). The association between various levels of alcohol consumption and an increased risk of liver cancer remains difficult to interpret even with the pooled data used in this meta-analysis. This difficulty results from the fact that, as discussed earlier, the association between alcohol consumption and liver cancer is only indirect.

It doesn’t matter how much you drink – the risk to the drinker’s health starts from the first drop of any alcoholic beverage. For example, one way the body metabolizes alcohol is through the activity of an enzyme called alcohol dehydrogenase, or ADH, which converts ethanol into the carcinogenic metabolite acetaldehyde, mainly in the liver. Recent evidence suggests that acetaldehyde production also occurs in the oral cavity and may be influenced by factors such as the oral microbiome (28, 29). The researchers cited the change in public perceptions and tighter regulations for tobacco, which show the importance of public health campaigns and physicians explaining risks to their patients.

Can people’s genes affect their risk of alcohol-related cancers?

Consequently, any definite risk-benefit assessment for moderate alcohol drinking requires much more far-reaching analyses that are beyond the scope of this article but that in the future may provide important information from a public health perspective. A combined analysis of more than 200 studies assessing the link between alcohol and various types of cancer (i.e., a meta-analysis) sought to investigate this association in more detail. This meta-analysis found that alcohol most strongly increased the risks for cancers of the oral cavity, pharynx, esophagus, and larynx. Statistically significant increases in risk also existed for cancers of the stomach, colon, rectum, liver, female breast, and ovaries.

1. For example, when the investigators considered only studies reporting RRs not adjusted for tobacco use, the pooled RR for lung cancer at the highest level of alcohol consumption was 6.30.
2. The researchers cited the change in public perceptions and tighter regulations for tobacco, which show the importance of public health campaigns and physicians explaining risks to their patients.
3. Meta-analyses are studies that pool data from several studies, thereby substantially enhancing the overall number of cases evaluated.

2Statistical analyses generally do not lead to a calculated, accurate result but instead provide an estimate of the result. The 95% CI is the range of the value under investigation that with a 95-percent likelihood contains the true value. Despite this, the question of beneficial effects of alcohol has been a contentious issue in research for years. Community strategies can help communities create environments that reduce excessive alcohol use.

In terms of risk assessment, this meta-analysis confirms that high levels of alcohol consumption (i.e., more than four drinks per day) result in a substantial risk of cancer development at several sites. At the same time, other studies have shown that moderate alcohol consumption can have protective effects against certain types of heart disease. Accordingly, one must determine whether moderate alcohol consumption results in an overall favorable or unfavorable risk-benefit balance for the individual drinker or an entire population. This balance depends on the age, gender, and baseline disease rates among the members of a given population.

Risks start from the first drop

The 2020–2025 Dietary Guidelines for Americans recommends that adults of legal drinking age can choose not to drink, or to drink in moderation (two drinks or less in a day for men or one drink or less in a day for women). To date, no experimental evidence indicates that alcohol by itself can cause cancer—that is, that alcohol can act as a complete carcinogen. Over the past few decades, however, several animal studies have indicated that alcohol can have a cocarcinogenic, or cancer-promoting, effect. This means that when alcohol is administered together with other known cancer-inducing agents (i.e., carcinogens), it promotes or accelerates cancer development. This effect was noted for several digestive tract cancers, specifically cancers of the esophagus and the nonglandular forestomach5 (Doll et al. 1999).

There likely are additional cancers linked to drinking alcohol, Dr. Orlow says, but more well-designed studies (epidemiological and other) are needed to prove that alcohol is a contributing risk factor. The risk of developing cancer increases substantially with the amount of alcohol consumed and there is no safe level of consumption when it comes to cancer. Educating the public about the cancer risk from drinking alcohol, regardless of the beverage type, is especially urgent given the increase in drinking during the COVID-19 pandemic, Dr. Klein said.

Which Cancers Are Most at Risk From Drinking Alcohol?

The stomach of a hamster is divided into a portion that does not contain glands which secrete digestive enzymes (i.e., nonglandular forestomach) and a portion closer to the intestine that does contain such glands. 4Statistically significant means that the observed result would occur by chance under hypothesized conditions less than a specified proportion of the time (usually 5 percent).

“We need to really make sure that we reinforce the message that all alcohol increases cancer risk,” she said. Noelle LoConte, M.D., an oncologist at the University of Wisconsin-Madison who studies alcohol and cancer risk, said that these findings confirm what doctors have long observed. DNA is the cell’s “instruction manual” that controls a cell’s normal growth and function. UICC supports WHO’s efforts to achieve a reduction in the harmful use of alcohol in line with the targets included in the SDG 2030 agenda. This requires concerted action by countries, effective global governance and appropriate engagement of all relevant stakeholders. The policies and programmes currently prioritised by governments, however, are often not shaped by data alone.

Does Drinking Alcohol Cause Cancer? Learn About the Risks

In all, 229 studies (183 case-control studies and 46 cohort studies) met the eligibility criteria and were included in the meta-analysis. These studies, which reported a total of 115,199 cases, investigated alcohol’s effects on the risk for developing cancer at a total of 19 sites in the body or at all sites combined (see the table and figure for a summary of the studies and their findings for each of those sites). This meta-analysis includes most published information on alcohol and cancer and, the limitations discussed above notwithstanding, consequently provides the most accurate estimates of the RRs for common cancers considered to be alcohol-related. For example, the analysis was unable to identify a threshold level of alcohol consumption below which no increased risk for cancer is evident. Furthermore, this meta-analysis found that the association of alcohol with the risk for oral and pharyngeal cancer appears to be stronger than the association with esophageal or laryngeal cancer across increasing levels of alcohol intake.

There is strong and consistent evidence that drinking alcohol increases your risk of developing a cancer, based on a growing body of research. Alcohol is estimated to account for 6% of cancer cases in the U.S. — more than 75,000 per year — and nearly 19,000 cancer deaths, according to the American Cancer Society. Alcohol is the third biggest controllable risk factor for the disease, after tobacco smoking and excess weight. Department of Agriculture have defined moderate drinking as no more than one drink per day for women and no more than two drinks per day for men. But most Americans aren’t aware of this link, thanks to seemingly contradictory research and mixed messaging from public health experts. A study published in 2023 found widespread mistaken beliefs that the risk varies by beverage type, with the lowest cancer risk assigned to wine.

Therefore, one cannot draw any conclusions regarding a potential causal role of alcohol in the development of these cancers. “So, when we talk about possible so-called safer levels of alcohol consumption or about its protective effects, we are ignoring the bigger picture of alcohol harm in our Region and the world. Although it is well established that alcohol can causecancer, this fact is still not widely known to the public in most countries. The results of eight appropriate studies were pooled to determine the relationship between alcohol consumption and the risk of cancer at all sites combined. This analysis found that alcohol consumption of at least 50 grams (i.e., 4 standard drinks) per day significantly increased the risk of developing any type of cancer.

To control for this possibility, the investigators included separate analyses for men and women in their statistical models, where feasible. However, gender explained a significant portion of the observed variability in study results only for esophageal and liver cancer, but not for other types of cancers. Another limitation of this and other meta-analyses is that alcohol consumption levels may have been systematically underreported in several studies, leading to biased RR estimates. To determine the effects of alcohol on the risk for various types of cancer, the researchers used three statistical methods.