I had overweight people in mind. For both cases I'd argue that emphasizing the benefits of healty weight and the means of getting to/staying at that weight is the more effective approach, though.
I think it's important to not lose sight of the fact that maintaining a healthy weight is a challenge for nearly everyone and undermine what is currently working for those who are not overweight.
Furthermore, I think obesity has somehow found it's way to be more in line with the LGBT style movements of acceptance/tolerance instead of the changing view of addictions as disease instead of character flaws when it clearly should be much more like the latter.