When 70%+ are overweight, 40%+ are obese, even in age 20 to 30, and 20%+ are obese in age 12 to 19, I think it is reasonable to make statements referring to the population at large needing lifestyle changes.
Applying broad population-level statistics over the individual patient is inappropriate medicine. An obese person who is losing a medically significant amount weight without going on a diet should be a serious sign for cancer screening, not a "well, good for you" and having the obese person's concerns totally ignored. An obese person who is gaining medically significant amounts of weight without lifestyle changes should be a serious sign for fluid retention issues, kidney failure, etc., not a "eat less" and having the person's concerns totally ignored.
That's what I mean. I meant it in the least judgmental way possible (fat lotta good that did, eh?). I feel that "we" Americans keep looking for "quick fix" cures, and people are more than willing to sell them to us, but the classics never go out of style.