A disadvantage of any food with a reputation for being healthy is that you may use it as an excuse to overindulge, particularly in the case of convenient snacks like sweetened yogurt. While even the less healthy varieties of yogurt make for a nutritionally better snack than ice cream or baked goods like doughnuts, you'll cancel that out if you eat several cups of yogurt a day. The U.S. Department of Agriculture recommends limiting your overall dairy servings to 3 cups per day. That includes not just yogurt but any milk, cheese or other dairy products.