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Thirty U.S. states have enacted medical cannabis laws, and all but one of them include cancer in the list of conditions allowed. Such laws give cancer patients across the country access to a substance that remains illegal under federal law. Anecdotal reports suggest it’s helpful in managing symptoms of chemotherapy, like pain and nausea.

Shortly after toking up, a lot of marijuana users find that there's one burning question on their minds: "Why am I so hungry?" Researchers have been probing different parts of the brain looking for the root cause of the marijuana munchies for years. Now, a team of neuroscientists report that they have stumbled onto a major clue buried in a cluster of neurons they thought was responsible for making you feel full.