My two cents: Portion control doesn’t always mean don’t eat too much. For me it also means if I don't eat enough, I stop losing weight on F2S. I look at it like the tummy is my fireplace and I need to keep the fires burning. If the fire goes out, I stop losing fat. What's burning ‘in there’ for me is body fat as well as the food I eat; so for me at least, there is a point where too little food, regardless of exercise, will halt the fat burning. I'm not sure if it's the survival mode thing mentioned. I have read different schools of thought on that and so I’m not sure and it’s complicated. But for me, it’s simple, on F2S I need portion food throughout the day so I’m eating enough to keep the fires burning, but also never “too much” of course. My wife is on the diet too and 6 months ago said she stopped losing weight mysteriously. I told her to eat more. She didn’t, got nowhere, saw a nutritionist, and was told “eat more”. She did (all the while staying on F2S) and she started losing weight again. The body is a funny thing. It’s not as simple as fuel in/fuel out, at least not for me.