SEP 11, 2018 8:52 AM PDT

New Evidence Shows Marijuana Smoke is Not the Same as Cigarette Smoke, at Least, in Terms of Lung Disease.

WRITTEN BY: Amy Loriaux

A recent report published in the journal Breathe by scientists in the UK suggests that chronic marijuana smoking may not cause the same deleterious effects on the lungs compared to cigarette smokers. While cigarette smoking has been linked to chronic obstructive pulmonary disease (COPD) and lung cancer, the same cannot be said of marijuana. Specifically, chronic marijuana smokers do not present symptoms of COPD, and there is little evidence to suggest a link to lung cancer.

The report was written by Dr. Luis Ribeiro of Imperial College London and Dr. Philip Ind of Hammersmith Hospital in London. They challenge the assumption that smoking marijuana will lead to the same consequences as cigarettes. They stake their claim on the fact that, while there are few studies out there, those that do exist have found little evidence of a connection. “As healthcare professionals,” they write, “we deal with tobacco all the time, but we also need to know about the respiratory effects of marijuana to be able to advise our patients and colleagues.”

For example, marijuana smokers are less likely to develop COPD than cigarette smokers. To diagnose a patient with COPD, clinicians measure how well your lungs function. According to the authors’ clinical observations, the lungs of chronic marijuana smokers operate normally. This may be due to the respiratory technique many marijuana smokers apply, that is, to breathe in the smoke deeply and hold it longer than cigarette smokers. However, according to the authors, THC has been shown experimentally to cause bronchodilation (opening of the bronchial tubes) whereas cigarettes narrow the bronchial tubes. This bronchoconstriction can contribute to the development of COPD.

The data showing a link between chronic marijuana smoking and lung cancer is more mixed. The authors cite a Swedish study of 50,000 conscripts found a two-fold increase in rates of lung cancer in marijuana smokers than non-smokers forty years later. However, the authors indicate that this study suffered from fundamental flaws, such as only considering smoking history at the time of conscription. On the other hand, a pooled analysis of six studies found no evidence of an increase in the risk of lung cancer. Other studies have found premalignant changes in lung biopsies of marijuana smokers, but this is not enough to conclude that they will develop lung cancer. The authors note THC or other cannabinoids may even prevent lung disease based on marijuana’s reported anti-inflammatory effects.

Despite these differences, there are some shared symptoms between chronic marijuana and cigarette smokers. Both populations can suffer from bouts of coughing, increased sputum production, wheezing, and acute bronchitis. Yet the similarities seem to stop there.

The report concludes that we should not speculate on the health risks of marijuana based on the effects of cigarettes. Nevertheless, the authors warn that the lack of evidence connecting marijuana with lung disease could be due to the low number of studies. More work must be done to state that there is a similarity.

Source: Breathe

About the Author
  • I currently work at a small CRO involved in clinical trial management.
You May Also Like
FEB 19, 2021
Cannabis Sciences
Canadians Use More Cannabis than Other Countries
FEB 19, 2021
Canadians Use More Cannabis than Other Countries
A survey conducted in 2020 by the Commonwealth Fund found that 23.1% of Canadians have used cannabis in the last year, s ...
MAR 05, 2021
Health & Medicine
Vaping Marijuana Worse for Teenagers Than Cigarettes or E-Cigarettes
MAR 05, 2021
Vaping Marijuana Worse for Teenagers Than Cigarettes or E-Cigarettes
Concerns over the potentially harmful effects of vaping have been growing recently and the results of a new study do lit ...
MAR 25, 2021
Health & Medicine
THC Detectable in Mother's Breast Milk for Six Weeks
MAR 25, 2021
THC Detectable in Mother's Breast Milk for Six Weeks
The effect on babies whose mothers consume cannabis while they are in the womb or breastfeeding is inconsistent and not ...
APR 17, 2021
Cannabis Sciences
Psychosis from Cannabis Use Linked to Genes for Schizophrenia
APR 17, 2021
Psychosis from Cannabis Use Linked to Genes for Schizophrenia
For some time now, cannabis users have been known to be at risk of developing psychosis more often than nonusers. Now th ...
MAY 06, 2021
Cannabis Sciences
New CBD Analog Outperforms Regular CBD for Pain Relief
MAY 06, 2021
New CBD Analog Outperforms Regular CBD for Pain Relief
Researchers from Temple University Health System have found that a novel cannabidiol (CBD) analog can reverse pain sensi ...
JUN 08, 2021
Health & Medicine
THC Level in Body Fluids Is Not a Good Marker of Impairment
JUN 08, 2021
THC Level in Body Fluids Is Not a Good Marker of Impairment
It’s not easy to tell how impaired a person will be based on how much THC they have in their body a study has foun ...
Loading Comments...