I think it would be hard to measure the "benefit" of cigarette. Nicotine addiction is more serious than heroin as an addiction. So, if someone who smokes goes some time without their fix, then when they do light up, they satisfy the craving - which will have a kind of "relaxing" effect. So, it would be easy for the smoker to confuse this relazing feeling as a result of feeding the habit with feeling better. Yes they feel better temporarily, but only because they've fed the craving - in my opinion. If there are at all any benefits to cigarette smoking, I'd say the same as chemotherapy or something to that effect - poisons the body at the same time.

I have suffered anxiety probelms all my life due to OCD (from the fillings), but have never resorted to either smoking or alcohol to "relieve" the symptoms - it's a dangerous road, in my opinion. Both smoking and alcoholism have devastating effects not only on the body, but the local environment and the lives of families and community.