the spiritual dangers of smoking
Please explain.
Do we need to explain the spiritual dangers of suicide? U’shmartem is just as much a mitzva as any other, if not more (as it is Doche most other mitzvos). Furthermore, secondhand smoke kills as well, so there is Retzicha involved.
Seriously, if someone had to choose between a ham sandwich & their first smoke (not skipping a single smoke, as that would be a different question), hypothetically (and I am not a Rabbi!) I would imagine halacha would say they should eat the ham.