We all know that “drinking alcohol is bad for you,” but a new study out of Korea has emphasized just how bad a few drinks can be. Cancer is the second leading cause of death globally, accounting for an estimated 9.6 million deaths in 2018.1 Alcohol consumption is the third major, modifiable cancer risk factor after tobacco use and obesity, and it is an established cause of at least seven types of cancer.2 In the United States alone, alcohol contributes to 5% of all cancer occurrences and 3% of all cancer-related deaths. However, the proportion of these cancers that occurred in the oral cavity/pharyngeal region was greater than 45% and the proportion that occurred in the laryngeal region was greater than 25%!3 This incredibly high alcohol-induced cancer rate of the oral/pharyngeal/laryngeal region was independent of smoking; if the two risk factors are combined, the percentages are much higher.
The Korean Health Services studied 4.5 million adults for two years, with a 6.5-year follow-up tracking the incidence of cancer.4 Participants were categorized based on alcohol consumption. Fourteen grams of alcohol is about one beer or one glass of wine or a 1.5 oz. shot. Alcohol consumption was categorized as none (0 g/d), mild (<15 g/d), moderate (15–29.9 g/d), and heavy (30 or more g/d). In other words, moderate drinking was one to two drinks per day, and heavy drinking was more than two drinks per day.
The study showed a dose-dependent relationship between the development of all types of cancers and the amount of alcohol consumption:
- Individuals who moderately drank (one to two drinks per day) had a 10% greater chance of developing all types of cancer as compared to those who did not drink.
- Those who drank heavily (more than two drinks per day) had a 34% greater chance of developing all types of cancer as compared to those who did not drink.
According to study author Dr. Neal Freedman, this is one of the first studies to suggest that altering alcohol consumption can have a meaningful change on the risk of developing all types of cancer and in particular, cancers that affect the oral cavity/pharynx, and larynx.
Before we freak out over having a few glasses of wine a night, we must look at the limitations of this study. First, data was collected from a self-reported questionnaire and participants may have underreported how many drinks they had per day. Second, the study was over a short period of time; a much longer time interval is needed to analyze a dose dependency between alcohol and cancer rate. Third, the study did not assess the role of aldehyde dehydrogenase enzyme dysfunction (known to be higher in the Asian community5) among participants as it relates to cancer. Finally, there might have been unmeasured confounders such as stress, mental health factors, lack of physical activity, nonreported smoking, etc., that influenced study outcomes.
With that being said, cessation or cutting down on alcohol use is never a bad idea.
Related reading: Sugar consumption: Damaging more than just teeth
- Bray F, Ferlay J, Soerjomataram I, Siegel RL, Torre LA, Jemal A. Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin. 2018;68(6):394-424. doi:10.3322/caac.21492
- Connor J. Alcohol consumption as a cause of cancer. Addiction. 2017;112(2):222-228. doi:10.1111/add.13477
- Sauer AG, Fedewa SA, Bandi P, et al. Proportion of cancer cases and deaths attributable to alcohol consumption by US state, 2013-2016. Cancer Epidemiol. 2021;71(Pt A):101893. doi:10.1016/j.canep.2021.101893
- Yoo JE, Han K, Shin DW, et al. Association between changes in alcohol consumption and cancer risk. JAMA Netw Open.2022;5(8):e2228544. doi:10.1001/jamanetworkopen.2022.28544
- Matsumura Y, Stiles KM, Reid J, et al. Gene therapy correction of aldehyde dehydrogenase 2 deficiency. Mol Ther Methods Clin Dev. 2019;15:72-82. doi:10.1016/j.omtm.2019.08.004
Editor’s note: This article originally appeared in Perio-Implant Advisory, a chairside resource for dentists and hygienists that focuses on periodontal- and implant-related issues. Read more articles and subscribe to the newsletter.