Here are two hard truths from Stephen Guyenet, a researcher at the University of Washington.

First, there may be no perfect solution for the obese:

“Obesity is not always going to be 100 percent reversible. I know no one wants to hear that, but I’m not in the business of selling snake oil. Some people can reverse it completely; others won’t lose any fat at all; the majority can probably lose a substantial amount of fat but not all of it. Highly controlled diet studies in rodents show that obesity due to eating highly rewarding/palatable refined food is mostly reversible when they are placed back on low-palatability whole food, but they don’t usually lose all of the excess fat, and the longer they’ve been obese, the less fat they lose (1, 2, 3). The capacity for the fat mass “setpoint” to re-establish at a lower level may diminish over time, varies between individuals, and probably also depends on other factors that no one currently understands. I think it’s important to be kind to yourself, and not set unreasonable expectations.”

– Stephen Guyenet, Food Reward: a Dominant Factor in Obesity, Part VII.

Next, if there is a solution, prepackaged foods are not it:

“If you think you will be able to find a way to lose fat and remain in long-term health while eating mostly commercially processed food (including restaurant food), you are fooling yourself. Processed food is the main problem, and if there is a solution, it is to avoid it. If you aren’t willing or able to eat mostly home cooked food made from basic ingredients, as every healthy culture does, you will have to accept a higher likelihood of fat gain and disease. That is the cold, hard truth.”

– Stephen Guyenet, Simple Food: Thoughts on Practicality.