Real frozen yogurt cannot be completely sugar free. Traditionally, yogurts are made from milk, which contains natural sugars, including lactose. However, no-sugar added varieties of frozen yogurt exist. Slightly lower in calories, they often contain artificial sweeteners in place of added refined sugar.
One cup of nonfat frozen yogurt typically contains about 160 to 200 calories, depending upon the specific flavor. Homemade varieties made with plain yogurt, fresh fruit, sweetened condensed milk and plain milk contain about 260 calories per cup. While homemade recipes may not add white refined sugar directly, some of the ingredients used to make them already contain added refined sugar, such as the sweetened condensed milk.
No-sugar added frozen yogurts in commercial establishments typically sweeten their products with sugar substitutes, such as sorbitol or sucralose. Your body does not recognize sucralose. The compound passes through the body without being broken down for energy. Sorbitol may cause excess gas and/or diarrhea when consumed in excess.
Many yogurt manufacturers post the calories of their product on a per ounce basis or per half-cup. However, the serving sizes offered contain significantly more than half a cup. A typical small frozen yogurt contains 1.5 servings, a large contains 3.5 servings and an extra-large contains six or more servings. For a no-sugar added frozen yogurt containing about 100 calories per serving, an extra-large portion provides more than 600 calories.