Nutritional epidemiology studies within the EEB have increasingly relied on biochemical and anthropometric measurements to complement dietary interviews. Several large studies of breast and endometrial cancer are attempting to disentangle the roles of fat, calories, animal products, and other aspects of a Westernized diet. Patterns of weight gain, body fat deposition, physical activity, alcohol consumption, and endogenous hormone levels are being investigated along with diet. The breast cancer studies distinguish between exposures at menarche and during early reproductive life and later exposures. Several methodologic studies have been incorporated into a breast cancer study to assess errors in dietary and anthropometric data. Studies of cervical cancer, in the U.S. and in Latin America, are evaluating the protective role of micronutrients, specifically carotenoids, vitamin A, vitamin C, folate, and selenium, with both dietary and biochemical techniques. The possibility that nutrient status may play a role at a specific stage of cervical carcinogenesis is being examined with prospective and retrospective studies. The reduced lung cancer risk consistently associated with vegetable and fruit intake in white men has been examined in women and blacks. Whether ~-carotene, other carotenoids, or other vegetable and fruit constituents explain this reduction in risk of lung and other squamous tumors is a major research focus. Laboratory techniques appropriate for large-scale epidemiologic studies have been developed for stabilizing and measuring individual carotenoids and vitamin C in serum.
