Whenever you see the word “low” on the label, that should be your clue to keep looking a little further. One important number that people forget to look at is the serving size and total calories on the Nutrition Facts label. Low-fat foods (especially fat-free foods) may have the same amount of calories as regular versions of those foods. The reason for this is that when fat is removed flavor is diminished. As a result, manufacturers will many times add sugar to make the food taste better. The addition of sugar adds calories. The bottom line is that low fat or fat-free foods don’t give you the license to eat all you want.

Additional Resources:
http://www.cspinet.org/reports/dinersgu.html