The Zone Diet has been around for a while. It’s known as “a calorie-restricted diet that is protein-adequate, carbohydrate-moderate, and low in fat” (Dr. Sears.com). It won’t cause hunger or fatigue.

How does the diet work? Is it safe? Is it effective? Natalie Allen, a registered dietitian and clinical instructor of biomedical sciences at Missouri State University, answers these questions and more on Openfit.