Teen Marijuana Use Associated with Higher Depression Risk
In an investigation, published in the journal JAMA Psychiatry on 2/13/2019, researchers at Oxford and McGill Universities went over 11 studies, covering just over 23,000 teens under the age of 18.
They concluded that even though individual-level risks remain moderate to low and their results should be further studied in a more adequately powered prospective, there could be a high (37%) increase in the risk that depression will be developed in young adulthood, up to 32 years of age. This also could cause a greater risk of suicide, even considering the persons existing mental health, but it has no significant link between marijuana use and future anxiety issues.
The 11 studies analyzed did not display any information on how much marijuana the teens smoked, or what the potency was. The subjects were teens decades ago so cannabis was a lot less potent than it is now and could greatly skew results.
The results of this study should be interpreted with caution, even though the implications are very strong, as it has been based on only a small number of published studies. With around 20% of seniors in high school using marijuana at least once a month, more studies need to be done.
As with any drug, this is an important public health concern, which should be properly addressed, especially as laws start to be placed.
On the other hand, we could look at the already legal drug, alcohol, and see the same similarities, if not worse. There have been many studies over the years and the American Addiction Centers state, "The connection between alcohol and depression is undeniable". Although depression can cause alcohol addiction, it is even more common for alcohol to cause depression. There has also been a correlation to anxiety.
It could also be possible that depression has caused marijuana use but there just hasn't been enough research. The main difference between the two is that we know what alcohol does, we have the research and the studies. Now we need that for marijuana, especially when it is being used recreationally.