Studies have shown that any of the most widely used weight-loss diets can help you lose weight if it causes you to eat fewer calories. For example, weight-loss experts have found that diet plans that emphasize certain foods or food combinations actually succeed by making you more aware of what you eat and, as a result, leading you to limit your calories. That includes the famous Atkins diet as well as other high-protein, low-carbohydrate diets. No study has shown that any diet that restricts or advocates a particular type of food helps you lose weight without calorie reduction.
Very simply, to lose weight, you have to limit total calories and be active enough to burn those calories on a daily, ongoing basis. So choose a diet plan that you can stick with, and calorie reduction will likely result. Harvard nutrition researchers do not endorse any single diet plan, but they do recommend a three-pronged strategy for losing weight.