Often, fat-free yogurt is actually worse for you. As fat is removed from the yogurt, something needs to be added to make it taste good again. Enter, sugar. Typically, about 1 gram of sugar is added for every 1 to 2 grams of fat removed. For example, Yoplait's Original Strawberry packs 26 grams of sugar per 6-ounce container, despite being 99 percent fat free.