Low-fat and fat-free have become popular and profitable labels on hundreds of new products on grocery-store shelves, yet Americans are more obese than ever. Lulled by the promises of "guilt-free" cookies, ice creams, chips and other nutritionally empty foods, many people have unwittingly increased their carbohydrate intake by consuming these lower-fat products, and researchers suspect that it's making people fatter.

Some of the nutrition researchers from the United States, Europe and Australia will convene this month at UT Southwestern to debate the optimum ratio of fats and carbohydrates in the diet.While there are no specific Recommended Dietary Allowances for carbohydrates or fats, the American Heart Association and the National Cholesterol Education Program recommend that 30 percent or less of total calories come from fat, 50 percent to 60 percent from carbohydrates and 10 percent to 20 percent from protein.

Would less fat be better? What happens when fat intake goes down to, say, 15 percent and carbohydrate intake goes up to 75 percent? An increased carbohydrate intake may raise blood triglyceride and glucose levels and insulin requirements. Or what happens if fat intake increases 10 percent, but the increase is from helpful monounsaturated fat, and carbohydrate intake declines to 40 percent? Would that be a better diet for a diabetic?

It's questions like these that the world's experts will explore at the Second International Conference on Fats and Oil Consumption in Health and Disease: "How We Can Optimize Dietary Composition to Combat Metabolic Complications and Decrease Obesity" April 22-23 on UT Southwestern's North Campus. Dr. Scott Grundy, director of the Center for Human Nutrition, will co-chair the conference with Dr. Martijn Katan of the Agricultural University.