The results of a clinical trial reported in yesterday’s Annals of Internal Medicine showed that low-carb diets helped people lose weight better than low fat diets. A report in today’s Journal of the American Medical Association tells a somewhat different story. A review of 48 head-to-head diet trails showed that average weight loss on either a low-carb or low-fat diet for 12 months was the same, about 16 pounds. And when the researchers compared named diets, which ranged from the low-carb Atkins and South Beach diets to moderates like Weight Watchers and Jenny Craig and low-fat approaches like the Ornish diet, all yielded similar weight loss. The main message from careful comparisons of different diets is that there’s no single diet that’s right for everyone. Any healthy diet can help people lose weight. And there’s more to a diet than weight loss. What’s needed for long-term health is an eating plan that can be followed day in and day out that is good for the heart, bones, brain, and every other part of the body. One eating strategy that can provide all that is the so-called Mediterranean diet.