I did Medifast three years ago and lost weight. I did it again in September and have lost weight. I followed the plan 100% exactly and was very successful. However, you can still do very well on the program by tinkering with it. I have known people who have lost weight on Medifast by NOT following the program to a tee. Their weight loss is slower, but they still lost weight. I agree with above poster...calories are calories...it's the nutrition that's different. But, don't be fooled, you cannot sustain 800-1000 calories a day normally. My advice is to do Medifast the way it is, 100% until you lose an amount of weight you are happy with and then continue on your own. Otherwise, you are better off just doing it on your own without Medifast products. IMHO, they are too expensive to waste on not following the plan 100%. KWIM? right now, I am trying to figure out a way to do T&M without the use of Medifast products and gently increase my calorie count.