Frozen yogurts are a healthier alternative to ice cream. Most are fat free, but high in sugar, so always in moderation. While most frozen yogurt is nonfat or very low in fat the calories still add up. Most nonfat “original” or “plain” (typically the lowest-calorie flavor at most frozen yogurt shops) is about 30-35 calories per ounce with about 20g of sugar—meaning that a large 16-ounce cup weighs in at 380 calories and 76g of sugar before adding any toppings.