Smoking is the primary cause of lung cancer. However, among never-smokers light to moderate alcohol consumption seems to lower the risk of lung cancer compared to non-drinking. That is the conclusion of a large international study that was recently published in the scientific journal International Journal of Cancer.

Only never-smokers
Light to moderate alcohol consumption (0-20g/d) appears to lower the risk of lung cancer compared to non-drinking. That appears from a large pooled analysis of 22 studies¹ involving only people who have never smoked. Because alcohol and smoking are strongly related, it is difficult to draw conclusions on the effect of one of them. That is why the researchers from this study only looked at never-smokers. In that way they are able to specifically look at the association between alcohol and lung cancer.

Beer, wine or spirit
When looking at the difference between beer, wine and spirit, the results suggest that the risk of lung cancer is lower with light to moderate wine consumption (0-30g/d) and with light spirit consumption (0-5g/d). The researchers give two possible explanations for these differences between beverage type. Previous studies would have suggested that flavonoids in wine may reduce the risk of some cancers, including lung cancer. Another explanation is that wine drinkers have an overall healthier lifestyle compared to beer drinkers and therefore a lower risk of cancer. The observed association between spirit and lower risk of lung cancer is more difficult to explain.

Amount of alcohol
Alcohol consumption was estimated as lifetime average grams of alcohol per day. Consumption frequency, changes in consumption patterns and beverage-specific alcohol content were taken into account. The researchers indicate that non-drinkers may represent a unique group and that the associations could be confounded by factors related to this group, such as socio-economic status and medical condition despite the fact that this has been adjusted for in the analysis. The researchers also indicate that confounding by other factors cannot be excluded.

Reference:
1. Fehringer, G., Brenner, D. R., et al. (2017) Alcohol and lung cancer risk among never smokers: A pooled analysis from the international lung cancer consortium and the SYNERGY study. International Journal of Cancer, vol. 140, nr. 9, pp. 1976-1984.