Here’s a weird one. What do you do with a famous advocate for medical marijuana who also thinks that cannabis concentrates should be illegal.

Dr. Rav Ivker has got some pretty real street cred in the medical marijuana field. He published the book Cannabis for Chronic Pain, which is like a real serious book from a major publisher that argues for responsibly using cannabis to treat pain.

And while Ivker is still very gung-ho about MMJ advocacy and recommending marijuana to his Boulder-area patients, he’s taking some possibly controversial opinions with regards to concentrates and cannabis addiction.

“I think they should be illegal,” Ivker told Westword. “In fact, I hope they become illegal. The only thing they’re good for is getting really high. But they’re high-risk, and there’s really no benefit from them.”

So now “getting really high” doesn’t count as a benefit?

To be clear, Ivker is not actually opposed to all concentrates. In fact, he says that he prescribes loads of CBD oil to his patients. CBD is a “ really a remarkable medicine,” he said. “I’ve been a family doctor for 46 years, and I’ve never seen a medicine as effective for pain without any downside.”

Another perk of CBD, according to the good doctor, is that it carries “no addiction problem.” That’s right. Ivker is concerned about cannabis addiction, and he’s not the only one. A study by the National Institute on Drug Abuse says that 9% of marijuana users become dependent, and also says that that number can go as high as 17% for users who start in their teens. As Westword reported, another story broke in the Washington Post lately which indicated that cannabis addiction is on the rise.

The reason for this, according to Ivker, is the recent increase in weed potency. The doctor says that when people were making claims that cannabis wasn’t addictive a decade or two ago, they were talking about a drug that usually contained 5-10% THC. “But today — and we’re talking about just the marijuana flower — the highest sativa strains can contain 25 to 30 percent THC. That’s what most people are smoking. And what they’re dabbing can be two or three times more potent than that.”

Ivker does not, in the Westword article, get into how exactly THC causes addiction, or any study which shows that it does, but he does make some sense when he puts cannabis addiction into a larger context. “Marijuana, like any substance or behavior that affects the reward system of the brain, has the potential for dependence and possible addiction,” he says, “and that includes food, sex and even television.”

But then why isn’t he arguing to make food, sex, and television illegal?