Host Jonathan Bastian talks with ethnobotanist Dr. Cassandra Quave about the amazing medicinal potential of plants and her global search for natural compounds — long known to traditional healers — that could help save us from the looming crisis of untreatable superbugs. We also hear from Dr. Marion Nestle, New York University professor emeritus of nutrition, food studies, and public health, on the health benefits — both real and fictitious — of nutritional supplements. From probiotics to vitamins, why do we take supplements without any scientific evidence that they do any good?