The incidence of oral cancer ranges from one to 10 cases per 100,000 people in most countries. The prevalence of oral cancer is relatively higher in men, in older people, and among people of low education and low income. Tobacco and alcohol are major causal factors.
–World Health Organization
Regardless of sex or whether or not the participants smoked or drank alcohol, the researchers pointed out that with each cup of coffee they consumed, their risk of death from this form of cancer dropped.
The study, overseen by the American Cancer Society, began in 1982. None had cancer at the beginning of the research, and during more than 2 decades of follow-up, 868 deaths from oral or throat cancers occurred.
Why coffee? “We really don’t clearly know the mechanism,” Hildebrand says. “But we do know that coffee contains hundreds of biologically active compounds.” Many of them, she continues, are now known to have cancer-fighting properties.
However, her team says their findings need to be verified by further research, and should not be used as a reason to recommend everyone to drink 4 cups of coffee a day.