Does no sugar added mean the same thing as sugar free?

What’s your guess? Actually, the terms have different meanings. "Sugar free" means that a food contains less than 0.5 grams of regular sugar per serving. This does not apply to sugar substitutes. "No sugar added" means that the processing and packing does not increase the sugar content over the amount naturally found in the ingredients. For example, a fat-free fruit yogurt made with aspartame may claim that it has "no sugar added" because it is sweetened with a sugar substitute in place of regular sucrose. However, it cannot be called "sugar free" because the product still contains sugar - the milk it is made with contains natural sugar lactose and the fruit in it contains the natural sugar fructose.
Excerpt from:
16 Myths of a Diabetic Diet 2nd ed.
Karen Hanson Chalmers, MS, RD, LDN, CDE
Amy Peterson Campbell, MS, RD, LDN, CDE