I feel the same way. I suffered when I was overweight and I see diet- and lifestyle-related suffering in everyone around me. But hardly anyone is open to the idea that you're better off not relying on any substance like alcohol or tobacco or pot to make yourself feel better, when all you need is to eat naturally and be active. People equate exercise with being tired, sore, sweaty and miserable. And just about everyone is an honest-to-god sugar addict. Reason and logic don't work when you talk to addicts.
Anyway, before I go off on too much of a tangent, I used to talk about it freely when the subject of health and fitness came up, but now I try to keep my mouth shut unless the other people seem open to new (old?) ideas.
You lousy kids! Get off my savannah!