A single cigarette produces enough smoke to alter genes in the lungs according to a study in the American Journal of Respiratory and Critical Care Medicine.  This could have consequences for your vision as well.  We know that smokers are more prone to cataracts and macular degeneration. Considering the amount of people that are exposed to second hand smoke or partake in an occasional cigarette,  some of the increased incidents of vision loss may be preventable.

Avoiding smoky environments may not only be good for your lungs, but your vision as well.