If a person smokes cannabis occasionally, it doesn't effect the work of his lung as bad as tobacco. This announcement was made by the stuff of University of Alabama and the University Of California. According to ABC News they came to this conclusion after looking at the results of 5000 people who use drugs and smoke cigarettes.
The scientists measured the volume of th elungs of research participants and how easyly they fill with the air. During next 20 years the servey was repeated several times. As it turned out, the condition of cigarettes smokers got worse, while the cannabis smokers didn't (only exception is people who use cannabis on a regular base in big ammounts).
For this reason, Dr Stefen Kertez came to the conclusion that "Moderate consumptionof cannabis is generally harmless". Let's note that the average survey smoked cannabis 2-3 time a month, while the cigarette smokers were doing it up to 8 times a day.
The scientists also found that the avarage man inhale 4 liters of air a second. Those who smokes cannabis occasionally - 4 liters and an extra 50 ml, which shows that th ework of lungs improved.