As more countries relax their cannabis laws, scientists are paying closer attention to its long-term effects on health.
Although many people know that tobacco smoking can seriously damage the lungs, less is known about what happens after years of cannabis use.
A new study suggests that cannabis can also harm the lungs, but in ways that are different from tobacco.
The research was carried out by scientists at the University of Otago in New Zealand and was published in the American Journal of Respiratory and Critical Care Medicine.
One of the lead researchers, Professor Bob Hancox, said the findings provide some of the strongest evidence yet about how long-term cannabis use affects breathing and lung function.
The study used information from the famous Dunedin Multidisciplinary Health and Development Study, which has followed the health of more than 1,000 people born in Dunedin during 1972 and 1973. Researchers tracked the participants from birth until they reached 45 years of age, creating one of the world’s most detailed records of lifetime cannabis use and lung health.
About three-quarters of the participants had tried cannabis at least once during their lives. Because cannabis has been illegal in many countries for decades, long-term studies like this have been rare. This has left many questions about its health effects unanswered until now.
The researchers found that long-term cannabis smoking caused the lungs to become overinflated, meaning they held more air than normal. Cannabis users also had greater resistance to airflow, making it harder for air to move through the lungs. These changes were even more noticeable than those seen in many tobacco smokers.
The study also showed that cannabis reduced the lungs’ ability to transfer oxygen into the bloodstream. Until recently, this problem was thought to be mainly associated with tobacco smoking. The new findings suggest that heavy cannabis use may also interfere with this important job of the lungs.
Doctors have previously described a severe form of emphysema in some heavy cannabis users, often called ‘bong lung.’ The researchers believe the changes seen in this study could represent early warning signs that appear before this serious lung damage develops. Detecting these problems early may help doctors better understand how lung disease progresses.
The findings also confirmed that cannabis and tobacco do not damage the lungs in exactly the same way. This means people who smoke both substances may be exposed to two different types of lung injury at the same time. According to the researchers, this combined effect could place even greater strain on the respiratory system.
Although the study provides valuable evidence, the scientists say more research is still needed to understand why cannabis affects the lungs differently from tobacco. As cannabis becomes more widely available for medical and recreational use in many parts of the world, understanding its long-term health risks has become increasingly important.
The study published in the American Journal of Respiratory and Critical Care Medicine reminds us that smoking any substance is not without risks.
People who are concerned about their lung health should speak with their healthcare provider and consider ways to reduce or avoid smoking to help protect their breathing and overall wellbeing.
If you care about lung, please read studies about a review of COPD-friendly foods for lung health, and can Vitamin C and E help fight lung cancer.
For more health information, please see recent studies about how diet influences lung health, and these vegetables could benefit your lung health.
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