This is probably one of those "how long is a piece of string" things, but... How long do you consider "long term" weight loss, or "keeping the weight off"?
I have read about so many diets that claim long-term weight loss, or "lose the weight and keep it off" but they never seem to be able to demonstrate results longer than just to the time it takes the subject to get to their target weight, or maybe a year at most.
I was very interested in a feature in a newspaper last year that was all about "losing the weight & keeping it off" but they didn't do any 1, 2 year followup on the subjects. They just followed them for a couple of months.
What is your definition of "long-term" weight loss? For me it's 5 years+, but maybe I'm expecting too much?