Well, I’ve been looking for medical proof the past 8 years that smoking really is that bad for you, but have never been able to find it – all I’ve found is conjecture, sensationalism and bad quotes by reverends and law professors. Statistical studies containing only 8 or 12 subjects are bad science, so I’ve looked long and hard for hard science on the matter containing (and I’ve frequently stated I’ll reject many scientific requirements) at least N > 100!
Now you’d think with the witch hunt going on against smoking and everybody just knowing that it’s bad for you (just like we knew the world was flat, yeah?) there’d be plenty on the matter all over the web. I’ve defied plenty of people to find it for me, and after 8 (!!!!!) years someone has found something for me:

http://bmj.bmjjournals.com/cgi/content/full/309/6959/901
(Mortality in relation to smoking: 40 years’ observations on male British doctors
R Doll, R Peto, K Wheatley, R Gray, I Sutherland)

Looking at this study, I found this quite
interesting:

In table I the first 2 columns indicate that he had about twice as
many smokers as non-smokers in the study in 1951. Which is,
coincidentally, about the same ratio of non smoker to smoker deaths by cancers etc
in the table III! Egads – this result is neatly replicated in table
IV.

They then make some pretty pictures, which actually make it look like
there might not be so much difference between smokers / stopped
smokers / non smokers.

The appendix table is interesting, as it shows what a load of bollocks
statistics are:
non smokers seem to almost never die of lung cancer, BUT (especially
considering the ratio of 1:2) they seem to die a lot more than smokers
of ‘other cancers’ at all ages as well as having higher probabilities
of vascular diseases, cirrhosis, ‘other medical’, non-medical deaths.
Finally, it looks like in ‘all causes’ non-smokers (still considering
the 1:2 ratio of the study) die more at all ages, except at 70-74 and
especially at 65-69 (just after they’ve retired!).

So there we go – smoking is actually quite good for you 🙂