Products with the hemp derivative are widely available, but health benefits are unproven.

Twice a day, Joe Tanko puts a drop of CBD tincture under his tongue — and waits for the active ingredient to be absorbed. “Golfing makes my back sore,” says Tanko, 62, of Pelham, Alabama. “It's pretty miserable waking up through the night with the pain.” But he says that since he started using CBD this year, his back feels fine and his sleep is undisturbed. “It also helps me to concentrate better,” he notes, which he says has helped improve his golf game. CBD (cannabidiol) is the trendy cannabis compound with a supersized health halo and market presence. While some states still restrict or ban CBD products, and their legal status remains murky and confusing, they are increasingly available at retailers and online.

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