Doctors in Scotland said that smoking marijuana just once or twice a day for a number of years could lead to serious lung disease, Reuters reported March 21.
“It might be that the psychoactive part of cannabis is harmless but the actual process of smoking, whatever you are smoking, can do your lungs harm,” said Dr Martin Johnson of Glasgow Royal Infirmary.
As part of the study, Johnson and fellow scientists studied four men with a type of emphysema. There was no other genetic susceptibility or explanation for the lung disease except that all four men were heavy cannabis smokers.
“When you smoke tobacco cigarettes they normally have a filter and that protects you to a certain extent. But when people smoke marijuana they tend to roll their own or smoke a pipe so they are not protected from some of the noxious substances,” Johnson explained.
He added that smokers of marijuana take much bigger breaths and hold them for much longer, compared to cigarette smokers. “It could be that these two element together might explain this association,” Johnson said.
The study is published in the journal Thorax.