It reminds me of the part in Der Untergang where everyone lights up the moment Hitler is dead (you can find it at 1.15 on the video link).
https://www.youtube.com/watch?v=QLmnTOQ2YpM
It's always struck me as a bit of a no-brainer. As a reformed heavy smoker (in my twenties I thought nothing of getting through fifty a day) you have to have world class self-denial to avoid the fact that it is doing you terrible harm. The coughing and wheezing first thing in the morning, the breathlessness after any physical activity, the chronic listlessness that heavy smoking brings.
I sometimes wonder what humankind could have achieved if we'd never smoked. A lot of very great men and women were only working at about 80% capacity.
To get back to the OP, if the Nazis had run a genuine scientific study comparing the physical, intellectual and psychological condition of a group of smokers and non-smokers, they would have undoubtedly found that the smokers scored lower, if only due to the decreased oxygen to the brain (as an aside, I once started smoking again in the middle of a chess game against my computer. We were fairly well matched at level 50 or so until I lit up and suddenly the computer started thrashing me. I had to drop it down to level 36 to get a decent game).
The Allies looked very closely at Nazi scientific research to do with hypothermia, anoxia, depressurisation etc. If there had been a proper scientific study of the effects of tobacco smoke it may have kick started research which led to the first proven link with fatal diseases a decade earlier than OTL.
A couple of other pictures to illustrate the debate. The first is a Nazi anti smoking poster talking about the financial penalties of the hideous habit.
"Two million Strength Through Joy Cars missed!"
And my personal favourite, The Chainsmoker: He doesn't consume it, it consumes him!"