Kratom, which has been linked to many deaths in the US, has been grown in Southeast Asia for centuries. There, people drink a tea made from the herb, with no ill effects. Why the difference?
Some supplement products contain substances that are harmful.
Getty Images / David Malan
Americans love their supplements, but some of the products are contaminated with heavy metals, bacteria and toxic fungi. The FDA has little control because of a law passed in 1994.