WALTER WILLETT, MD, DrPH, is a professor of epidemiology and nutrition and chairman of the department of nutrition at Harvard School of Public Health and a professor of medicine at Harvard Medical School. His bestselling book Eat, Drink, and Be Healthy helped change the USDA Food Pyramid. He lives in Cambridge, MA.
MALISSA WOOD, MD, is a clinical cardiologist and staff physician at Massachusetts General Hospital in Boston, codirector of the Corrigan Women's Health Program, assistant professor of clinical medicine at Harvard Medical School, and the lead investigator of the HAPPY Heart trial. She lives in Concord, MA.
DAN CHILDS is the managing editor of medical coverage for ABC News. He lives in New York City.