If you crave fat:
It's well-known that eating sweets and simple carbohydrates can lead to the infamous sugar crash that leaves you craving more. Consuming fat has a similar self-perpetuating effect, says Sarah Leibowitz, Ph.D., an associate professor of neurobiology at Rockefeller University, in New York City. "Eating fatty foods stimulates the brain to produce peptides that make you crave more fat," she says. A recent study at the Scripps Research Institute, in Jupiter, Florida, showed that rats who were fed high-fat foods (bacon, icing) began eating more and more--a hallmark of addictive behavior. (They actually refused nutritious food when it was offered.) Fight the urge for chips by eating plenty of lean protein and low-fat dairy products, which will help you feel more satisfied.