Cannabis vs Tobacco Smoking

The Old Toker, recently sent me a MedPage Today article on the age-old argument of Cannabis vs Tobacco.  Scanning the article, I learned that MedPage Today was presenting age-old information. The article quotes a 2007 study out of Ottawa that has long been refuted.  Is Cannabis smoking less or more harmful than Tobacco smoking?  Once again, let’s look at the evidence.  MedPage Today, you owe me.  
 
Despite a lack of updated information, Dr. Donald Tashkin, M.D., after a 30-year career as a UCLA Pulmonologist, has the definitive answer for the Tobacco vs. Cannabis question.  He is well known for his studies on Cannabis smoking, emphysema, and lung cancers.  In his long career, Dr. Tashkin received several grants from the NIH, specifically from NIDA, to study the effects of smoking Cannabis on lungs.  In his 2013 publication titled,  Effects of Marijuana Smoking on the Lungs, he concludes  "...the accumulated weight of evidence implies far lower risks for pulmonary complications of even regular heavy use of marijuana compared with the grave pulmonary consequences of tobacco.”  One Tashkin study even found a Cannabis using cohort had significantly less lung cancer than the Control cohort. His comment refutes the conclusion of earlier studies, including his own, and stands as the definitive response to the Cannabis vs Tobacco smoking question.   
 
That being said...Smoking anything is not a medically recommended habit.  The ash debris from inhaled smoke is a lung irritant.  The heat of the smoke contributes to lung tissue damage. If you can avoid the habit, I recommend it.  A correlation with Cannabis smoke and chronic or recurrent bronchitis, notes Dr. Tashkin, is the only significant long-term effect to date.
 
Many people smoke Cannabis for its acute effects.  Physiologic muscle relaxation settles the body.  In mere minutes cannabinoids pass through the lungs, enter the bloodstream, and rush to the brain. The immediate stress and anxiety relief after inhaling Cannabis is a welcome outcome.  Molecular models explain how cannabinoids attach to receptors in the central nervous system and at the nerve-muscle junction causing these relaxing effects.  Tobacco, paradoxically, produces similar results. The difference is that Tobacco works by activating the sympathetic “fight or flight” system whereas Cannabis affects the parasympathetic “rest and digest” system. The sympathetic nervous system acts in defense to danger whereas the parasympathetic nervous system repairs or heals.  Is this is why Cannabis smoke is associated with a better outcome than Tobacco smoke?

In regard to the dangers of smoking, the evidence continues to pile on.  Results from a prospective longitudinal lung study were recently published in Respiratory Medicine, a peer reviewed science journal  The study followed a group of people from birth, testing the lung function of Cannabis and Tobacco smokers at age 21 and 30.  The results align with Dr. Tashkin’s conclusion.  Tobacco smoking (with or without Cannabis) restricts lung function.  However, Cannabis smoking alone does not consistently affect lung function. 
 
Does this put the question to rest?  Not really.  In science, there is always the pursuit of more evidence.  At least MedPage Today can now report evidence that is relevant. 
 
Smoking is the most popular method of Cannabis use. However, there are other means of inhaling.  Vaporizing machines can be used to inhale Cannabis flower vapor produced at lower temperatures.  Vape carts or vape pens do the same but use Cannabis oils with higher potencies.  There isn’t much evidence on the long-term effect from inhaling oil vapors. Vape pen users beware.  In 2019, some manufacturers of Vape Pens added Vitamin E oil in their products which resulted in illness and even death.  EVALI is a serious condition in which a person’s lungs become damaged from substances contained in e-cigarettes or vaping products. It’s appropriate to note that no deaths have been reported that directly result from inhaling the smoke of Cannabis flowers.  Maybe, in this case, the old way is the best way.