Professor of psychiatry at University of Colorado Anschutz Medical Campus, Christian Hopfer, says that today’s marijuana is 5-times stronger than marijuana from the 1970s and 1980s. He’s one of the leading authors on a $5.5 million marijuana study that is expected to be the longest “analysis of cannabis to date.”
For research purposes, Hopfer visited Colorado Business Insider reports.and found strains boasting 25% THC,
Since 1995, THC content in marijuana has tripled. Samples seized by the DEA reveal that in 1995, marijuana averaged 4% THC, and samples from 2014 indicate 12% THC on average.
Hopfer said, “It used to be 2 – 5%, so this stuff is potent.”
Research also indicates that the CBD percentage in marijuana has decreased from 1:14 CBD/THC ratio in 1995 to 1:80 ratio in 2014. Although, data will vary due to strain and growing techniques. Furthermore, THC degrades over time, so if a sample sits a while, the THC percentage indicated may be incorrect.
In 2014, a study published in the journal Addiction, indicated that marijuana users adjust their dosing based upon potency. They’ll use less when the strain is stronger.
Hopfer says that dosing needs to be addressed. He said, “I think we’ve dealt with marijuana historically from a criminal justice perspective, but if you switch to an environment where it’s legal, you switch to a public health perspective. And to do that right, we need more scientific research.”