The participants who were regular coffee drinkers, that is, those who drank an estimated four or more cups a day, compared with those who were non-drinkers, had a 39 percent decreased risk of oral cavity and pharynx cancers combined.
Data on decaffeinated coffee was too sparse for detailed analysis, but indicated no increased risk. Tea intake was not associated with head and neck cancer risk.
The association is more reliable among those who are frequent, regular coffee drinkers, consuming more than four cups of coffee a day.
"Since coffee is so widely used and there is a relatively high incidence and low survival rate of these forms of cancers, our results have important public health implications that need to be further addressed," said lead researcher Mia Hashibe, assistant professor in the department of family and preventive medicine at the University of Utah, Salt Lake City, and a Huntsman Cancer Institute investigator.
"What makes our results so unique is that we had a very large sample size, and since we combined data across many studies, we had more statistical power to detect associations between cancer and coffee," Hashibe added.
Cancer Epidemiology, Biomarkers and Prevention editorial board member Johanna W. Lampe believes this current analysis by Hashibe and colleagues provides strong, additional evidence for an association between caffeinated coffee drinking and cancer risk.
"The fact that this was seen for oral and pharyngeal cancers, but not laryngeal cancers, provides some evidence as to a possible specificity of effect," said Lampe.
"These findings provide further impetus to pursue research to understand the role of coffee in head and neck cancer prevention," she added.
The results have been published online in Cancer Epidemiology, Biomarkers and Prevention, a journal of the American Association for Cancer Research.