DIET AND NUTRITION IN THE ETIOLOGY OF ORAL-CANCER

Epidemiological studies worldwide have implicated dietary and nutritio nal factors in the development of oral and pharyngeal cancer. Dietary information in these case-control studies generally was collected thro ugh food-frequency questionnaires. Consistently, these studies observe d a protective effect of a diet high in fruit intake, reflected in a 2 0-80% reduction in oral cancer risk. A high intake of foods considered to be dietary staples in particular cultural groups, possibly indicat ing a generally impoverished diet, has been linked to excess risk. Ind igenous dietary practices that in single studies were found to increas e risk include a high intake of chili powder and wood stove cooking. S upplementation with various vitamins has been protective in a few stud ies. Chemoprevention trials generally have found that chemopreventive agents reduce the size of oral leukoplakia lesions or the frequency of second primary oral cancers. The most consistent dietary findings acr oss multiple cultural settings are a protective effect of high fruit c onsumption and the carcinogenic effect of high alcohol intake.