It depends on if you stick to the program and make the lifestyle changes necessary for success. I’ve never tried it, but a good friend of mine has it and has lost weight with it. She tried it once and lost some weight, but then quit and gained back the weight she had lost. Now she’s doing it again and actually sticking to a routine and eating better and has lost weight (and inches) again. Once she finishes it, she will have to continue eating right and continue exercising to keep herself at a healthy weight. If she doesn’t stick to the lifestyle change, it won’t last.