http://edition.cnn.com/2012/06/05/he...t2fit-lessons/
There's a professional in the field, a personal trainer, who wasn't very successful in what he was doing, because he thought like so many ignorant people in this thread do; that it's just as easy as "eat less, move more", and that people just use excuses a lot, and that it isn't hard.
He decided to gain 70 pounds, and then drop it all. If you read the article, the experience opened his eyes to the fact that it isn't quite as simple as people, who have never been in that situation, and who absolutely have no idea what the hell they're talking about, think.