In the aisles of the grocery store, the menus of chain restaurants, even in one's own refrigerator, confusion about how to eat right reigns- Is low-carb good or is carbo-loading the better way to go? Fat-free or sugar-free? And when did those dreaded eggs become a health food? Americans are hungrier than ever for clear-cut answers to their most perplexing food questions, but a private nutritionist or a membership in a diet club are expensive luxuries...