Walter C. Willett, MD, DrPH

Dr. Willett's research in the coming year will extend his investigation of the relationship between early life diet, adult diet, adiposity, hormonal influences and breast cancer risk. In their previous analyses he and his colleagues have found that intake of high-fat dairy products were associated with risk of pre-menopausal breast cancer, possibly due to the hormone content of these foods.

In new projects, with support from BCRF they will: Continue the analyses of nutritional factors and breast cancer from the large international cohorts; examine the effects of milk intake in Mongolian girls on blood levels of growth hormones; and continue their follow-up of a unique group of adolescent girls who have provided detailed information on diet and lifestyle that will be related to growth rates and, ultimately, breast cancer.

Over the past year, Dr. Willett and his team examined associations between carotenoid and vitamin intakes and risk of breast cancer in the Pooling Project of Prospective Studies of Diet and Cancer, an international consortium of multiple cohort studies. These analyses supported by BCRF (which are different from those supported by NCI) are in process and will include data from 19 prospective cohort studies that met pre-specified inclusion criteria for the Pooling Project. To date, the researchers have received the breast cancer outcome data from 13 studies and have subsequently checked their data for accuracy and formatted their data for inclusion in the Pooling Project database.

In the current dataset of 13 studies with over 954,000 women, more than 31,500 (3,721 ER-negative) breast cancer cases were identified during follow-up. By pooling data from multiple prospective studies of diet and cancer, the researchers can conduct uniform analyses across studies with much greater power than the individual studies possess and provide the most reliable information on these associations.

Over time, Dr. Willett's research and the research of others has shown that diet in early adult life and adolescence predicts risk of pre-menopausal breast cancer and other hormone-dependent cancers.

Mid-Year Progress Report:
Dr. Willett reports that his team is continuing the analyses of the relationship between nutritional factors, body size and breast cancer risk from pooled data coming from 23 large international cohort studies of women. They are in preparation stages for another study examining the effect of milk intake in Mongolian girls on blood levels of growth hormones. These early hormone levels are likely related to breast cancer risk in later life. Finally, the researchers continue their follow-up of a unique group of adolescent girls who have provided detailed information on diet and lifestyle that will be related to growth rates and, ultimately, breast cancer. These analyses draw on existing studies; thus, they efficiently provide new information that can potentially identify strategies for reducing risk for all women.

Bio:
Dr. Walter Willett is Professor of Epidemiology and Nutrition and Chairman of the Department of Nutrition at Harvard School of Public Health and Professor of Medicine at Harvard Medical School. He grew up in Madison, Wisconsin, studied food science at Michigan State University, and graduated from the University of Michigan Medical School before obtaining a Doctorate in Public Health from Harvard School of Public Health.

Dr. Willett has focused much of his work over the last 25 years on the development of methods, using both questionnaire and biochemical approaches, to study the effects of diet on the occurrence of major diseases. He has applied these methods starting in 1980 in the Nurses' Health Studies I and II and the Health Professionals Follow-up Study. Together, these cohorts that include nearly 300,000 men and women with repeated dietary assessments are providing the most detailed information on the long-term health consequences of food choices.

Dr. Willett has published over 1,000 articles, primarily on lifestyle risk factors for heart disease and cancer, and has written the textbook, Nutritional Epidemiology, published by Oxford University Press. His book for the general public, Eat, Drink and Be Healthy: The Harvard Medical School Guide to Healthy Eating, has appeared on most major bestseller lists, and he has recently published a second book, co-authored with Mollie Katzen, for a general audience, Eat, Drink, and Weigh Less. Dr. Willett is the most cited nutritionist internationally, and is among the five most cited persons in all fields of clinical science. He is a member of the Institute of Medicine of the National Academy of Sciences and the recipient of many national and international awards for his research.