A study has found that smoking a single cannabis joint is as harmful to a person's lungs as having up to five tobacco cigarettes.
In a study published Tuesday, in the British journal Thorax, experts at the Medical Research Institute of New Zealand showed that cannabis use stopped the lungs from working properly. The damage rose in proportion to the number of joints smoked.
Researchers tested 339 volunteers, divided into cannabis smokers, tobacco smokers, smokers of both, and non-smokers. Cannabis smokers complained of wheezing, coughing, and chest tightness, which researchers attributed to damage in the lungs' small airways that transport oxygen.
However, the study concluded that only tobacco use caused emphysema, a crippling lung disease.
Some information for this report was provided by AFP and Reuters.