As more states legalize marijuana, there’s growing interest in a cannabis extract — cannabidiol, also known as CBD.

It’s marketed as a compound that can help relieve anxiety — and, perhaps, help ease aches and pains, too.

Part of the appeal, at least for people who don’t want to get high, is that CBD doesn’t have the same mind-altering effects as marijuana, since it does not contain THC, the psychoactive component of the plant.

“My customers are buying CBD [for] stress relief,” says Richard Ferry, the retail manager of Home Grown Apothecary in Portland, Ore., where recreational marijuana use is legal under state law, with some restrictions.

Another rationale Ferry’s heard from clients about their CBD use: “Their mother-in-law is in town, and they just want to chill out!”

“CBD has gotten a lot of buzz,” Ferry says, as he displays an array of CBD products, including capsules and bottles of liquid CBD oil that users dispense under the tongue with a dropper.

By one estimate, the CBD industry has doubled in size over the last two years, and is now worth $200 million. But with this popularity the hype may have gotten ahead of the science.

“There’s a lot of confusion about how it [CBD] works and what it does exactly,” Ferry says.

Researchers now are trying to nail down CBD’s effects.

“I think there’s good evidence to suggest that CBD could be an effective treatment of anxiety and addiction” and other disorders, says Dr. Esther Blessing, a psychiatrist and researcher at New York University. “But we need clinical trials to find out.”

So far, evidence of the substance’s anti-anxiety effect comes from animal research and from very small, short-term human studies that suggest CBD exhibits anti-inflammatory and anti-anxiety properties. To red more from Allison Aubrey, click here.