Moderate Alcohol Use Linked with Higher Cancer Risk in WHO Study

Researchers with the World Health Organization (WHO) have found an association between moderate alcohol use and a substantially higher risk of several cancers, including breast, colon, and oral cancers, according to a press release.¹

This increased cancer risk was found even among light to moderate drinkers, defined as those who have 1 to 2 drinks per day. This group represented 1 out of every 7 new cancer diagnoses worldwide in 2020, equating to more than 100,000 cases globally.¹

“All drinking involves risk, and with alcohol-related cancers, all levels of consumption are associated with some risk,” said co-author Jurgen Rehm, PhD, senior scientist with the Institute for Mental Health Policy Research at the Centre for Addiction and Mental Health, in a press release. “For example, each standard sized glass of wine per day is associated with a 6% higher risk for developing female breast cancer.”1

Alcohol can cause cancers in several ways, although the most common is through impairing DNA repair. Other ways include liver cirrhosis due to chronic alcohol consumption and a dysregulation of sex hormones, which can lead to breast cancer. Alcohol use can also increase the risk of head and neck cancer among individuals who smoke, because it increases the absorption of carcinogens.¹

“Alcohol consumption causes a substantial burden of cancer globally,” said Isabelle Soerjomataram, MD, MSc, PhD, deputy branch head of the Cancer Surveillance Branch at the International Agency for Research on Cancer, in the press release. “Yet the impact on cancers is often unknown or overlooked, highlighting the need for implementation of effective policy and interventions to increase public awareness of the link between alcohol use and cancer risk, and decrease overall alcohol consumption to prevent the burden of alcohol-attributable cancers.”

Researchers conducted a modeling study based on alcohol exposure data from almost all countries of the world. The data included both surveys and sales data, which were combined with the most recent relative risk estimates for cancer based on level of consumption.¹

Globally, the investigators estimated that 4.1% of all new cancer diagnoses in 2020 were attributable to alcohol consumption. Of these, men accounted for 76.7%, and breast cancers, esophageal cancers, and liver cancers contributed the most cases.²

The researchers calculated population attributable fractions (PAFs)—the fraction of all cases attributable to alcohol—based on region. They found that PAFs were lowest in northern Africa and western Asia, and highest in eastern Asia and central and eastern Europe.

The largest burden of alcohol-attributable cancers was represented by “heavy” and “risky” drinking, which were defined as more than 60 g of alcohol per day and between 20 and 60 g per day, respectively. Moderate drinking contributed to 13.9% of cases.²

Rehm said research into the link between alcohol consumption and cancer is relatively new and that public policy does not yet reflect these risks. For example, Rehm said governments could consider adding warning labels on alcohol containers, similar to labels on tobacco products.¹

“As an epidemiologist, I would recommend higher taxes to fully reflect the burden of disease from alcohol,” Rehm said. “Along with limiting the physical availability and marketing of alcohol, price controls are recognized as high-impact, cost-effective measures to reduce alcohol-related harm.”¹

REFERENCES

1. New WHO study links moderate alcohol use with higher cancer risk. News release. Centre for Addiction and Mental Health. July 13, 2021. Accessed July 21, 2021. https://www.camh.ca/en/camh-news-and-stories/new-who-study-links-moderate-alcohol-use--with-higher-cancer-risk
2. Rumgay H, Shield K, Charvat H, Ferrari P, et al. Global burden of cancer in 2020 attributable to alcohol consumption: a population-based study. The Lancet Oncology. July 13, 2021. Accessed July 21, 2021. https://www.thelancet.com/journals/lanonc/article/PIIS1470-2045(21)00279-5/fulltext