Retailers across Canada are struggling with a shortage of all cannabis, but there's one product they're especially desperate to keep on shelves: cannabidiol or CBD, a non-intoxicating extract vaunted for its purported health benefits. The extract, most commonly sold as oil, has been promoted as a natural cure for pain, anxiety and insomnia, despite limited medical research. Many customers are coming in asking for it, especially first-time and older users, store owners say. "I don't...
