I do believe there is some truth to the "one shot" theory. At least in my situation. I started lowcarbing the Atkin's way almost 4 years ago. I lost all the weight that I needed to (about 30 pounds at the time) REALLY QUICK and I kept it off for several years. It was like a miracle!!! I couldn't believe I was eating bacon, fat, cream, butter, etc. etc and still losing. It literally melted right off my body the first time around on Atkin's. Well although I did a good job keeping the weight off for several years, I did eventually slip back into eating bad. I SWORE that I never would but I became very depressed and turned to cookies, cake, chips, pizza, bread, pasta, ice cream, doughnuts, etc. etc. to comfort me. Well needless to say, I put on about 30 pounds again in a year!!!!! Well I decided to try Atkin's again and to my suprise it didn't work near as well as the first time around!!! I lost a few pounds but nothing significant. Don't get me wrong...........I WAS STILL LOSING, but not very much and it was very slow!!!! The first time I dropped all the weight in about 2 months but the second time around it took 6 months to lose half of what I did the first time!!! So I finally gave up on Atkin's and switched over to Stillman's which is a VERY lowcarb diet. I lost the final pounds doing it that way and it only took a couple of weeks!!! Now I'm back on Atkin's and maintaining. I WILL NEVER STRAY FROM LOW-CARB WOL AGAIN!!! I do not want to have to work ten times harder the next time around. Good luck and hang in there! I hope it's not hard for you to lose the 2nd time around like it was for me. Everyone is different and this was just my scenerio.