Occasional marijuana use doesn't harm lungs, study finds

January 12, 2012 By Shari Roan, Los Angeles Times

Smoking marijuana on an occasional basis does not appear to significantly damage the lungs, according to a new study.

The paper, published Tuesday in the , adds to some previous research that has also failed to find a link between low or moderate exposure to marijuana smoke and . The issue has gained some importance in recent years, however, as marijuana usage rates rise and as states considered legalization of marijuana for medical or even recreational purposes.

Even a low level of has been linked to a higher risk of respiratory problems, pulmonary disease and lung cancer - as has exposure to secondhand tobacco smoke. Thus, the idea that marijuana smoke may also be harmful is reasonable. Marijuana contains many of the same chemicals as tobacco smoke.

Researchers led by Mark Pletcher at the University of California, San Francisco, studied 5,115 men and women in four U.S. cities regarding their current and to tobacco smoke and marijuana smoke and their . The exposure to marijuana smoke was expressed by joint years, with smoking 365 joints or filled pipe bowls being equal to one "joint year."

The study showed that lung function declined with increased exposure to tobacco smoke. However, that same pattern was not seen with . There was no evidence of lung function damage with seven joint years (or smoking one joint a day for seven years.) After 10 years, there was some decline in lung function as measured by the speed at which a person can blow out air.

The study should reassure people that medical uses of marijuana, such as for pain control, will not be offset by lung damage, the authors pointed out. But, they said, the study did not evaluate the effects of heavy marijuana smoking on the lungs.

"Our findings suggest that occasional use of marijuana for (medical) purposes may not be associated with adverse consequences on pulmonary function," Pletcher said in a news release. "On the other hand, our findings do suggest an accelerated decline in pulmonary function with heavier use - either very frequent use or frequent use over many years - and a resulting need for caution and moderation when marijuana use is considered."

Explore further: Marijuana smoke not as damaging to lungs as cigarette smoke

Related Stories

Marijuana smoke not as damaging to lungs as cigarette smoke

January 10, 2012

Using marijuana carries legal risks, but a new study shows that the consequences of occasionally lighting up do not include long-term loss of lung function, according to a new study by University of Alabama at Birmingham ...

Recommended for you

Losing sleep over climate change

May 26, 2017

Climate change may keep you awake—and not just metaphorically. Nights that are warmer than normal can harm human sleep, researchers show in a new paper, with the poor and elderly most affected. According to their findings, ...

Vitamin D supplements could help pain management

May 23, 2017

Vitamin D supplementation combined with good sleeping habits may help manage pain-related diseases. This paper published in the Journal of Endocrinology, reviews published research on the relationship between vitamin D levels, ...

Recommended daily protein intake too low for the elderly

May 23, 2017

You can find the recommended dietary allowance (RDA) on the nutrition labels of all your processed food. Food manufacturers are obliged to list the nutritional value of their products, and therefore must mention the percent ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.