A guy I know came up to me at an event, reeking of tobacco smoke. Seriously, I had to take a few steps backward because of the odor. Because I am a doctor, he launched into a story about a study he is in at Stanford, where they are testing him for some health factors. I couldn't quite follow what the study was assessing.
What was remarkable was that they said he is so healthy that they told him not to quit smoking because if he quit, his health might go downhill. Yes, he heard them say that being a smoker has helped his health.
It is hard for me to believe the doctors at Stanford advised him to continue chain smoking. He doesn't look particularly healthy, has a smokers voice and unhealthy smokers skin. Of course I do not know his underlying health status.
We can fool ourselves about most anything if we want to. But 10,000 studies don't lie and believe me, smoking is about the worst thing you can do to your body.