Nutrition and Cancer
Current research
After lung cancer, the most common cancers in Britain are cancers of the breast, bowel and prostate. We are studying the epidemiology of these cancers with the aim of identifying risk factors which can be modified to reduce the incidence of disease. We have shown that the concentration in the blood of oestradiol, the principal female sex hormone, is directly related to a woman's risk for developing breast cancer. Lifetime exposure to oestradiol may explain much of the epidemiology of breast cancer, including the increase in risk with obesity and a component of the variation in rates between countries. Prostate cancer risk is related to blood levels of certain growth factors. We are now looking for determinants of blood concentrations of oestradiol, testosterone and growth factors. In particular we are studying the relationship of dietary composition with hormone levels, to establish whether endogenous hormone concentrations are affected by dietary protein, dietary fibre and phytooestrogens and by polymorphisms of hormone metabolising enzymes. We are also studying the direct relationship of food and nutrient intake with the risk for developing cancers of the breast, prostate and large bowel.
Future projects
Molecular epidemiology will be used to study the interaction of nutritional and hormonal factors with genetic polymorphisms in the aetiology of common cancers. The European Prospective Investigation into Cancer and Nutrition (EPIC) is the largest study of diet and cancer ever undertaken. Dietary questionnaires, serum and DNA samples have been collected from 500,000 men and women in ten European countries. By using optimal methods for measuring diet and by including people with a wide range of dietary patterns, EPIC will produce substantially more accurate information than previous studies on the relationship of diet with the risk for developing cancer. The blood samples will be used to measure exposure to certain micronutrients and endogenous hormones, and to conduct genetic analyses to look for interactions between genotype and dietary and hormonal exposures.
