When I am at a gathering and it is known that I am an addiction specialist, dinner-party conversation always seems to veer towards my views on marijuana use, particularly in teens. It is clear that people feel strongly about the subject. However, often the evidence for what they are saying is poor or nonexistent.
To begin, we need to separate the legalization question from the medical question of whether the benefits of its use outweighs the risks. As far as legalization is concerned you may be surprised to know that I favor making marijuana legal for a number of reasons. First, I do not believe in a nanny state. Second, I believe the law should be consistent. If the government is to dictate our behavior, than all dangerous behaviors and substances should be made illegal. Alcohol would have to come off the shelves along with cigarettes, sodas and candy. Moreover, as the era of prohibition proved quite clearly, making a substance illegal may affect total consumption of a product, but does not affect the rate of addiction to that product. This makes sense, of course, because addiction, by definition, involves the loss of the effect of the negative consequences (such as getting arrested) of a given behavior upon the use of the drug.
That being said, there is a body of emerging scientific evidence implicating marijuana in negative behaviors and health outcomes.
Here is some data that I find pretty interesting.Early marijuana use (before the age of 21) appears to be more dangerous than use after that time. This makes sense given the fact that the prefrontal cortex is still developing in one’s late teens and early twenties.
For more information look here: https://www.sciencedaily.com/releases/2017/03/170328105901.htm
What is also becoming clear is the adverse effect of marijuana on school performance. This has been seen anecdotally for years but it is good to see some objective data on student grade point averages to support the claim.
For more information look here: https://www.sciencedaily.com/releases/2017/03/170308144728.htm
Then there is the issue of whether marijuana may actually cause or be associated with physical problems such as osteoporosis. This is of particular concern in heavy users.
For more information look here: https://www.sciencedaily.com/releases/2016/10/161012132657.htm
And now there is evidence from rat studies indicating that marijuana use can affect not only cognition, but the willingness to tackle cognitively difficult tasks.
For more information look here: https://www.sciencedaily.com/releases/2016/08/160824144033.htm
To be clear, I don’t think it very productive to debate whether marijuana is good or bad. There are studies showing its benefits and we hear about them every day. However, now it is becoming clear through objective studies that there are some very real risks here as well.