Stevia
Credit: Photograph by Svend Lindbaek

It may sound like a gimmicky name for an artificial sweetener, but stevia is actually a natural sugar substitute derived from the leaves of the South American stevia plant. "It's one of your best options because it has no calories or carbs, and studies suggest it may help control insulin resistance," says holistic nutritionist Lisa Turner.

Best uses: Flavor oatmeal, yogurt, cereal, and drinks with just a touch – stevia is far sweeter than sugar, and leaves a bitter, licorice-like aftertaste if you overdo it.