Stop smoking. Not that this is news. However, I'm still looking up info on the effect of incense, since most of my readers are Pagan (and some are Catholic, and some are Greek Orthodox, and some are Buddhist, and .....)
Starting with the tar, going on through the particulates, and the assortment of other chemicals naturally in tobacco, let alone in what is added to most cigarettes (and pipe tobacco, and cigars), it's all an insult to your body.
Oh, I also don't know the impact of smoking grass, hash, opium, etc. These are all smoked because getting substances into the body through the lungs is quick and easy. And the toxins in each of them enter the body just as quickly and easily as the psychoactive components.