Even very low daily alcohol consumption—around nine grams, equivalent to one standard drink—is associated with a sharp increase in the risk of cancer of the buccal and lip mucosa in India.

This conclusion was reached by the authors of a large comparative study published in BMJ Global Health. According to their estimates, the risk of developing the disease increases by about 50%, with the greatest danger associated with the consumption of locally produced, home-made alcoholic beverages.

Oral cancer is the second most common cancer in India. Each year, more than 140,000 new cases and about 80,000 deaths are recorded nationwide. Incidence continues to rise, especially among men. The predominant form of the disease in India affects the mucosal lining of the inner cheeks and lips, and fewer than half of patients survive longer than five years after diagnosis.

Because alcohol consumption is often combined with chewing tobacco, the researchers sought to disentangle the contribution of each factor individually as well as their combined effect. To do so, they compared data from nearly 1,800 patients with confirmed cancer of the buccal mucosa and almost 2,000 individuals without the disease, recruited from five regions of India between 2010 and 2021. Participants provided detailed information on the type, amount, and duration of consumption of both commercially produced alcohol and more than 30 types of local alcoholic beverages, as well as on the forms and duration of tobacco use.

The results showed that even minimal amounts of alcohol were associated with an increased cancer risk. Among people who consumed alcohol, the risk was nearly 70% higher than among non-drinkers, while among those who preferred local beverages it rose by almost 90%. Combined use of alcohol and chewing tobacco increased the risk more than fourfold. According to the authors’ estimates, about 62% of all cases of this type of cancer in India are attributable to this combination.

The scientists suggest that ethanol increases the permeability of the oral mucosa, making it more vulnerable to carcinogens present in tobacco. Toxic impurities such as methanol and acetaldehyde, which are often found in unregulated local alcohol, may also play a role. The authors emphasize that there is no safe level of alcohol consumption in the context of this type of cancer, and that measures to reduce alcohol and tobacco use could substantially lower the disease burden in the country.