It's s all about patterns not individual cases. Go to a McDonald's and you will understand, or a vape meet...
Everyone knows people who have smoked their whole lives and died old. Does that mean smoking is safe?
Obviously I have been in a McDonalds. If its the only place I can find to eat on the rare occasion I'm traveling I may even order something besides coffee, like a horrifying grilled chicken sandwich. I don't see the place filled with obese people though to my recollection. No more so than anywhere else I go.
I've never been to a vape meet. So more obese people vape than don't?