Fat consumption and breast cancer: preliminary results from the E3N-Epic cohort

Recent reviews have concluded that a high consumption of total, saturated o r animal fat could possibly increase the risk of breast cancer. However the se results are highly dependent on the type of study; indeed, most of the p rospective studies do not support this association. In this paper, we inves tigated the relationship between fat consumption and breast cancer risk in the E3N-Epic cohort, the French component of the European Prospective Inves tigation into Cancer and Nutrition. Assessment of fat consumption was based on daily intakes of food items and nutrients using a food frequency questi onnaire. Relative risk (RR) estimates were calculated using Cox's proportio nal hazards model. After an average of 3.4 years of follow-up, 838 cases of incident breast cancer were recorded in a study population of GS 879 women . The mean caloric intake was 2,073 kcal (SD 540), with 37% of calories com ing from fat intake. Milk products and vegetable oils were the main sources of fat in the diet. We found a small positive association between fat inta ke and breast cancer risk. Compared with the lowest, women in the highest q uartile of fat intake had a 37% higher risk of breast cancer (RR 1.37, CI95 % = 0.99-1.89. There was no detectable association between fatty acids or f ood items contributing to fat intake and breast cancer risk. These analyses suggest there is a need for longer follow-up time to increase statistical power and confirm these tendencies.