Myth that low-fat or fat-free means no calories..,is that true?

Fact:
A low-fat or fat-free food is often lower in calories than the same size portion of the full-fat product. But many processed low-fat or fat-free foods have just as many calories as the full-fat version of the same food or even more calories. They may contain added sugar, flour, or starch thickeners to improve flavor and texture after fat is removed. These ingredients add calories.
Tip:
Read the Nutrition Facts on a food package to find out how many calories are in a serving. Check the serving size too—it may be less than you are used to eating.

Source:
U.S. Department of Health and Human Services
NATIONAL INSTITUTES OF HEALTH
NATIONAL INSTITUTE OF DIABETES AND DIGESTIVE AND KIDNEY DISEASE (NIDDK)
Weight-control Information Network (WIN)