Most people would agree that a healthy amount of skepticism can be useful in all walks of life. Obviously, taking claims at face value and believing them as truth can lead to a lot of problems; people who make claims often have incentive to want to get you to believe those claims.

But one also must remember to keep skepticism in perspective. Take medical marijuana, for example. No one should take claims of what medical cannabis is capable of at face value, but when evaluating those claims we must also keep in mind what those claims are being compared to and how much scientific and anecdotal evidence there is to back up each.

At a recent Forbes Healthcare Summit, the former head of the Centers for Disease Control and Prevention, Tom Frieden, was asked about medical marijuana as a replacement treatment when it comes to pain management for those who rely on opioid pain medications.

“The huge problem with legalization is that in the current legal context of the U.S., if you legalize a product you cannot restrict its market, and what we’re looking at is the prospect of having Big Tobacco paralleled by Big Marijuana actively promoting marijuana use,” Frieden said. “It could be very harmful for some people and some communities. That said, there may be a role for some individuals, and obviously this is a tough issue.”

There are two glaring problems with this. One, opioid painkillers are already doing great harm to “some people and some communities,” with tens of thousands of people dying each year from overdoses; there are zero overdose deaths officially associated with cannabis use. To imply that drugs doing damage to people is taken into consideration when deciding when and where to prescribe them flies in the face of much evidence to the contrary.

The second major problem with the quote above is the notion that “if you legalize a product you cannot restrict its market.” Legalization is actually the only way to “restrict” and regulate a market. There are no restrictions on illegal cannabis sellers. Once they make the decision to sell marijuana illegally, they are beyond any care of restrictions. They have no incentive to check ID or to make sure their product isn’t full of harmful pesticides or to even make sure their product is of any quality to begin with. Sure, there are natural market forces that would provide them with those incentives, but government prohibition helps limit the amount of competitors those illegal dealers will face, limiting their reason to care about quality and safety.

To be skeptical is reasonable, but to act like there is a worry that legal marijuana is in any way more dangerous than prescription opioids is not reasonable in the slightest.