Barbara Rolls, Ph.D, holds the endowed Guthrie Chair of Nutrition at Penn State, has been president of the North American Association for the Study of Obesity and the Society for the Study of Ingestive Behavior, and has served on the advisory council of the National Institutes of Health's Institute of Diabetes and Digestion and Kidney Diseases. She is the author of three professional books on food and nutrition and more than 170 academic articles.Coauthor Robert A. Barnett is an award-winning journalist who specializes in food and nutrition. He is the author of Tonics (HarperPerennial, 1997), coauthor of The Guilt-Free Comfort Food Cookbook (Thomas Nelson, 1996), and editor of The American… Health Food Book (Dutton, 1991).