I watched the +The Biggest Loser the first season it was on and knew that not one of those contestants would keep their weight off after they resumed their real lives. Any idiot can lose weight by exercising eight hours a day and eating specially prepared food that you didn't have to cook yourself.
Nobody WANTS to eat box of donuts or fried chicken. They would rather NOT WANT to eat those things but whatever forces are lurking inside won't let them.
So since people who have to lose 100 plus pounds have BIGGER issues than not realizing they should exercise every day or should only eat one bagel instead of three, it's the exact same thing as being an alcoholic or smoking cigarettes. Until the reason they overeat is uncovered and acknowledged, nothing will ever permanently change.
New York Times Biggest Loser article
"I just like food!" No, sorry. People who LIKE FOOD, savor and enjoy it. They shop for and prepare quality meals. They are thrilled to get a tiny plate of carefully and expertly prepared food instead of going to an all-you-can-eat buffet.
Look at super-rich Oprah Winfrey selling +Weight Watchers. How many times does this accomplished lady have to lose weight, gain weight, lose weight, gain weight.... she has access to personal chefs and trainers, the best gym equipment. If SHE can't permanently lose weight, NO ONE can. And Weight Watchers is a very smart and sensible program, but people still 'quit' and go back year after year after year.
Sadly, the majority of overweight people end up staying overweight their entire lives, despite spending years tormenting themselves, like a permanent birthmark.