There's promising new science behind a viral supplement that people are taking for addiction

The Food and Drug Administration calls kratom a dangerous opioid with no medical use, but advocates say it's a life-saving supplement.

What's missing from the debate over whether kratom is miracle or menace, however, is hard science on how it works.

Frequently ground into a fine powder and taken as pills or tea, kratom is a psychoactive drug derived from the leaves of an Asian plant in the coffee family called Mitragyna speciosa. Kratom advocates swear by the stuff, saying it's helped them kick devastating addictions to opioid painkillers.

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