In addition to the fact that stevia comes from the leaves of a plant rather than a lab, the natural sweetener’s biggest draw is that it’s zero in calories. How does sugar compare? Well, 2 teaspoons have 30 calories and 8 grams of carbohydrates. While this may not sound like a lot, “people often use more than 2 teaspoons of sugar,” Aguirre says, “so the calories can add up quickly.” As she notes, many experts believe that sugar consumption is a major cause of obesity and many chronic diseases, such as diabetes, in the U.S.