Want a diet that you can stick to for the long term

The glycemic index diet is not a true low-carbohydrate diet because you don't have to count carbohydrates (carbs). Nor is it a low-fat diet. It also doesn't require you to reduce portion sizes or count calories. But the glycemic index diet does steer you toward certain types of carbs.

One study showed that participants following the Zone diet maintained a weight loss of about 7 pounds (3.2 kilograms) after one year — about the same amount of weight lost as in the three other diets in the study.

There have been few studies about the impact of the glycemic index diet on weight loss after a year or more. But some evidence suggests that a diet higher in protein and lower on the glycemic index may lead to sustained weight loss.

Some evidence also suggests that you may lose weight on a glycemic index diet simply because you choose more fiber and protein, which helps you reduce portion sizes and eat less.