If you think you're not as stupid because you smoke hand-rolled cigarettes, the Scientific Committee on Tobacco and Health of the British Government reports:

"Recent studies show that a significant proportion of tar yields from hand-rolled cigarettes can be greater than the current maximum limit of 15 mg per cigarette for commercial cigarettes, although due to the variable nature of the product, measurement of tar yields from hand-rolled cigarettes is not straightforward. A study undertaken by the Laboratory of the Government Chemist showed that few UK hand-rolled cigarette smokers use filters and high-porosity papers, both of which have played an important part in reducing tar yields in commercial products."