Oh man so many things are bad for you in this world. It's like that South Park episode where you had the overweight guy guzzling down burgers and fries and preaching against smoking so religiously. After you do it for a while, it just becomes such a pleasurable habit. The very air we breathe isn't perfect for us either. It's why nutritionists recommend you take in lots of anti-oxidants, because oxidation is what causes you to age and stuff (green tea, anti-aging blah blah). Generalizations, yeah. But our world is naturally poisonous. I take the good in with the bad.
I could spend my whole life trying to be perfect, but realizing I'll never get to that I just try my best in the meantime. You stop trying to live like other people and just live for yourself -- do what makes you happy. But that also doesn't mean you stop trying to better yourself, but don't forget to have some joys. Same argument can be made for liquor, or junk foods. They say jogging shakes up the insides of your body, so too much of that is bad too. If you're gonna smoke, go for American Spirits. Ditch the chemicals of the other brands and smoke pure tobacco. The only reason other companies add them (ammonia, arsenic, methanol) is to make them more addictive, to lessen the harshness of the tobacco taste, and to make the cigarette not last as long so you'll be running for another pack quicker. Really nasty practices, just goes to show you can sell people anything if your marketing is on point..