Agreed. My brother went on Jenny Craig and lost A LOT of weight. The only was when he stopped going he put the weight all back on, but that's because he didn't change his lifestyle or eating habits after stopping JC. So he back on it again, and lost all the weight again. Take with you what you learn while you're on it. But bottom line is, yeah, you can do whatever you put your mind to. You've just got to tell your mind who's boss.
Your better off not doing Jenny Craig if your looking for long term weight loss. Diets tend to just be short term and hard to stick with. I'd suggest looking up healthy eating on the internet or feel free to PM me and ill give you some tips, tricks, and info on nutrition and more in depth info about weight loss.
It works but it is costly. I don't recommend it at all. I am actually a lifetime member, but have only used it one time. I did lose alot of weight but had difficulty planning my meals because I was so used to the nuke'n'pukes,aka microwaved meals.
All I do now is watch my portions. That is the key. Everything in moderation.
Check your local hospitals for nutrition classes. I took a nutrition class at a local hospital, it was free. It was six weeks and very informative. Speaking with a nutritionist is great and I continue to consult mine as necessary.