The diet wars rage on. Results from a $415 million government-funded study released last week did not conclusively find that a low-fat diet lowered older women’s risk of cancer or heart disease, causing a flurry of concern. Dieters are wondering if they should throw out their scales and give in to fatty foods or switch to a higher-fat low-carbohydrate regime. And the real quandary: Does it pay to eat well? Read on…