It's a long-running trope, cannabis opponents cite the higher strength of marijuana today versus what hippies were smoking back in the '60s to argue against legalization. The argument goes that stronger weed causes bigger problems. At least this is what US surgeon general Dr. Jerome Adams thinks.
"The marijuana of even 10 years ago was less than 5 percent THC, which is the product that causes you to get high, which can cause addiction, which can cause problems," Adams told The Hill.
He went on to say that not only is today's weed stronger, but modern consumption methods like dabbing and vaping mean consumers are getting more THC out of even low-strength cannabis then ever before.
"The new strains that are professionally grown are 10, 15, 20 percent THC, and then when you vape them or dab them through these new devices, folks are getting 50, 60, 70 percent THC delivered," he said.
And while Adams isn't wrong to suggest that there has been past research linking high amounts of THC to potential cognitive issues, that's not the whole story. Much of this research has been conducted on THC which has been isolated from the rest of the plant's more than 110 other compounds called cannabinoids. THC may be harmful when taken by itself, but many researchers believe that when consumed together with the other cannabinoids the risk is significantly lowered.
Additionally, some studies have shown that many of the negative effects of excessive cannabis use can be mitigated by simply abstaining from use for a period.
There is one of Adams' cannabis warning that we can get behind, and that's the potential risks associated of consuming while pregnant.
"That's particularly harmful to the developing brain all the way down to the fetus," explained Adams. "We've heard of communities where up to one in five women report using marijuana during pregnancy. That's very, very concerning to me."
Most expecting parents know that smoking cigarettes and drinking alcohol while pregnant is a bad idea and doctors may even suggest avoiding certain prescription drugs during this time. Cannabis should probably be treated in the same way.
While it's still unclear exactly how cannabis consumption affects fetuses, much of the research we do have doesn't paint a good picture.