But first, why does smoking make you hungry?
"There are neurons in your brain that suppress hunger after you've eaten. When coming into contact with marijuana, the cannabinoids make these neurons flip, they switch over, ending up causing hunger, rather than eliminating it," Dr. Horvath said.
"Say you eat an entire Thanksgiving dinner, then come into contact with marijuana, and come back 45 minutes later ready to eat again -- this is not normal, from a systemic standpoint," he said. "But the reason is quite simple, really." Simple for a professor of comparative medicine and neurobiology at Yale University School of Medicine, maybe.