Actually, I believe it's excess calories that makes people fat, not the fat itself.
Otherwise we could all sit around and live off of soda and not get fat, right?
I think the human body is able to function well under many 'diet regimens'. I get so frustrated and confused reading all the different options, I don't know who to believe! LOL
I think we are all wired differently, so different things will work for different people for weight loss/not gaining too much weight. Things like ethnic background, food intolerances(that we should listen to and respect in ourselves) and allergies, all play a role.
We should go with whatever helps us to feel the best in our own body.