Passing up foods such as white rice and bagels for choices like lentils and grapefruit could help you slim down. In a Cochrane Library research review, dieters who focused on eating low on the glycemic index shed more pounds than participants on other diets.

The glycemic index, or GI, ranks carbohydrate-rich foods according to their impact on blood sugar levels: High GI foods are associated with a speedy rise and fall in blood sugar, while low-GI foods are said to keep blood sugar steady. You can look up GI values at websites such as glycemicindex.com. Or simply stick to the basics of a low-GI diet, suggests Rosanna Gibbons, R.D., consultant dietitian for the University of Maryland Center for Integrative Medicine. "It's about eating more complex carbohydrates, boosting your fiber intake, and choosing whole foods over refined foods," she says. "Those principles all dovetail with many of the nutrition goals we already advise." Combined with exercise and limiting calories, says Gibbons, following the fundamentals of a low-GI diet should lead to weight loss and better overall health.

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