Skip to main content

Verified by Psychology Today

Marijuana Is All Natural, So What’s the Problem?

Marijuana is not the harmless, safe substance many claim it to be.

In my psychiatric practice, I see a lot of adolescents and young adults, many of whom smoke marijuana. Many will tell me that marijuana is harmless and hasn’t caused any problems in their life. To bolster their claim, they will often add that if marijuana were harmful, why have two states legalized it and another handful of states made it legal to use medicinally? And they will add the clincher: “Besides, marijuana is all natural.”

Before I go on, I will offer two caveats to try to ensure that people don’t misinterpret what follows. First, despite being legal, I believe that alcohol is moderately to much worse than marijuana in most respects. And second, I think our country’s war on drugs is largely misguided and a waste of resources.

With those disclaimers out of the way, I now want to state unequivocally that marijuana is not the harmless, safe substance many might like to think, especially for those under age 30. Why? Because neuroscience has now shown us that the brain continues to develop until the late 20s, and using drugs while the brain is still developing can influence how it develops and result in moderate to potentially significant downstream problematic effects.

When adolescents use marijuana, for example, the white matter of their brains can undergo changes that are similar to the brains of individuals with schizophrenia. Perhaps it’s not surprising, then, that marijuana smoking in adolescence significantly increases the risk for eventually becoming psychotic and/or developing schizophrenia. This risk is even greater for people who had psychiatric symptoms before their first experience with marijuana and those with schizophrenia in their families.

And furthermore, more and more data are confirming the fact that marijuana users are also at increased risk for developing anxiety and depression later in their lives, as well as having memory deficits.

Suppose someone wants to comfort himself by saying that he only smokes once in a while—in what I might call the “almost addicted” range—and that therefore he is not at any increased risk for developing psychiatric issues as a result of marijuana use? Data show that even using marijuana occasionally can carry with it an increased risk of psychiatric disorders. For example, a Swedish study found a 70-percent increased risk of becoming schizophrenic for those who’d used marijuana just five to 10 times over their lifetime. These same researchers found that those who’d used marijuana more than 50 times in their life had amore than 600-percent increased risk of schizophrenia.

And it is not just psychiatric problems that can result from marijuana use. The vast majority of young marijuana users I have seen—and I grant that I might see a skewed sample in my medical practice—have seen their academic performance drop concomitantly with their marijuana use, their athletic prowess diminish, and difficulties within their families rise.

Marijuana is also potentially addictive. For more on this, see here. But even for those who do not progress to become addicted to marijuana, there is a realm between the casual user and the full-on addict that I label "almost addicted"—folks who don't meet anyone's definition of addiction but who might be having difficulties in their life as a result of their drug use nonetheless. For more on this in-between condition feel free to go here.

There is much more that I might write—and will in following posts—but suffice it to say that being “all-natural” does not mean that marijuana is safe and harmless. After all, the two biggest killers in our midst—namely tobacco and alcohol—are in and of themselves all-natural substances.

More from Psychology Today

More from J. Wesley Boyd M.D., Ph.D.

More from Psychology Today