Lifestyle changes are essentially standard medical advice. There is nothing wrong with proposing diet and exercise.
It's just that you should probably suggest other treatments in addition to the lifestyle changes that have relatively low long term efficacy.
Of course, that assumes your goal is to actually help the fatties instead of judging them.
> Of course, that assumes your goal is to actually help the fatties
I don't believe that's possible. They have to choose a healthier lifestyle by themselves.
It's not that people are fat because no one told them to eat healthy and exercise sometimes. They're fat because they have ignored that advice for a long time.
They aren't missing information about diet and exercise, they're missing diet and exercise.
You don't believe it's possible? Obviously it's possible! Look around, we have what are essentially miracle drugs available, and you are still pushing ideas that have mostly failed for the last 50 years!