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. Public health campaigns about the cancer risk posed by alcohol in England and Australia have been effective at raising awareness with their target audiences. There have been decades of public education campaigns about the health risks of tobacco, warning labels on tobacco products, and smokefree laws.
Cited by other articles
An estimated 1 in 20 cancers in the U.S. were attributed to alcohol use in 2019, the report stated, noting that starting drinking at an early age increases cancer risk later in life. Drinking 20 to 60 grams, two to six drinks, of ethanol alcohol per day, which the authors defined as “risky drinking,” represented 39.4% of alcohol-attributable cancer cases. Moderate drinking – defined as 20 or fewer grams, or up to two drinks, per day – contributed to nearly 14%, or 1 in 7, cases.
To determine the effects of alcohol on the risk for various types of cancer, the researchers used three statistical methods. Subsequently, they determined the relationship between alcohol consumption and the risk for a given type of cancer by fitting to the pooled data several statistical models called fractional models (Royston et al. 1999). Such models can identify trends (e.g., J- or U-shaped curves) as well as other relationships between alcohol exposure levels and relative risks. The investigators then chose the best-fitting model to summarize the relation of interest (Corrao et al. 1999). Next, they assessed whether gender modified the effect of alcohol on the risk for each neoplasm.
Alcohol and Cancer Risk
- Breast cancer in women came in third place for number of cases, with almost 100,000 cases (about 4% worldwide) attributable to alcohol use.
- Alcoholic drinks contain ethanol, which is a known carcinogen, and there are several ways in which it may cause cancer.
- This article summarizes the major findings of one such meta-analysis (Corrao et al. 1999, 2000).
“The breast cancer numbers are pretty high, just because breast cancer is so common,” Dr. LoConte explained. Similarly, for esophageal cancer, the researchers zeroed in on a type called squamous cell carcinoma, which is the only type known to be triggered by alcohol consumption. “This may make the estimates of alcohol-related cancers lower than previous studies, but they’re more precise,” said Dr. Abnet. The methods the WHO team used differ from those used in previous studies, Dr. Abnet explained. For example, instead of including all types of liver cancer, “they focused on hepatocellular carcinoma, the type of liver cancer that’s linked to alcohol,” he said.
And, he added, if drinking rises within a group, their cancer cases are eventually likely to rise as well. The study had several limitations, including that it only looked at current alcohol consumption, not past drinking habits, said Dr. Abnet. Surveys worldwide often have Drug Addiction Articles not collected information about past alcohol use, “but for a lot of people, there’s a pattern where they drink more heavily when they’re young and moderately as they get older,” he explained. Alcohol can also have more subtle cancer-promoting effects, including impairing the body’s ability to metabolize and absorb a variety of nutrients it needs to prevent cancer.
”While I don’t think that this report provides all of the answers, it is certainly a step in the right direction. More importantly, if we better understand cancer risk factors, this allows us to more effectively counsel our patients about behaviors that will ultimately help to prevent cancer diagnoses,” she added. The significantly greater risks seen in men carrying the low-alcohol tolerability ALDH2 gene variant who still drank regularly suggests that greater accumulation of acetaldehyde may directly increase cancer risk. The results remained the same when the data were adjusted for other cancer risk factors, such as smoking, diet, physical activity, body mass and family history of cancer. Because these alleles are allocated at birth and are independent of other lifestyle factors (such as smoking), they can be used as a proxy for alcohol intake, to assess how alcohol consumption affects disease risks. To address these unknowns, researchers from Oxford Population Health, Peking University and the Chinese Academy of Medical Sciences, Beijing, used a genetic approach by investigating gene variants linked to lower alcohol consumption in Asian populations.
“Alcohol can worsen the side effects of chemotherapy and drugs used during cancer treatment,” Bevers says, listing side effects including nausea, dehydration and mouth sores. “Cutting back one drink is a risk reduction, but the greatest risk reduction is going from three drinks to zero,” Bevers says. Men and women who choose to drink have different serving recommendations because of how their bodies respond to and break down alcohol. “This is a reminder of the impact of lifestyle choices that can have on cancer risk,” Harb said. The first mutation is a loss-of-function mutation in the gene for the enzyme aldehyde dehydrogenase 2 (ALDH2).
News and Highlights
Because cancer risk increases with the amount of ethanol consumed, all alcoholic beverages pose a risk. Numerous changes need to be made to raise public awareness of the fact that drinking alcohol raises the risk of several types of cancer. The cancer types with the largest numbers of alcohol-attributable cases were oesophageal cancer, liver cancer, and female breast cancer. The researchers also investigated whether gender modified the effect of alcohol intake on the risk for each type of cancer. Statistically significant gender differences existed only for esophageal and liver cancer—where the alcohol-related risk was higher in women than in men—but not for other types of cancer.
These analyses found that tobacco use had a substantial modifying effect not only on the alcohol-related risks for lung and bladder cancer but also on the risk for laryngeal cancer. 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. When they excluded such studies from the analysis and considered only studies reporting estimates adjusted for tobacco use, however, the pooled RR declined to 1.07. This finding indicates that alcohol itself only weakly increases the risk for lung cancer and that lung cancer risk primarily results from tobacco use, which is common in heavy drinkers. For laryngeal cancer, tobacco use also substantially influences the risk, though a strong association with alcohol consumption, indicated by a RR of 3.24, remained even when considering only studies presenting adjusted estimates.
In the United States alone, about 75,000 cancer cases and 19,000 cancer deaths are estimated to be linked to alcohol each year. Researchers and health professionals can do more to help break down these misconceptions, Dr. LoConte added. “We need to really make sure that we reinforce the message that all alcohol increases cancer risk,” she said.
The report authors called for increased efforts to help people make lifestyle changes that can reduce their cancer risk. About 1 in 5 cancer diagnoses are related to body weight, poor diet, alcohol use, and physical inactivity. Lifestyle awareness campaigns have been effective in the past, with declining smoking rates being linked to reduced cancer rates. The plant secondary compound resveratrol, found in grapes used to make red wine and some other plants, has been investigated for many possible health effects, including cancer prevention.
