Lithium is a potent drug used to treat bipolar disorder, but it’s also the third element in the periodic table, and you can find tiny amounts in most drinking water. Scientists have discovered something remarkable: In areas where the tap water has more lithium, fewer people seem to die by suicide. That raises a big question: Should we put small amounts of lithium in the drinking water? Can we afford not to? ––– Further reading: Anna Fels’s op-ed “Should We All Take a Bit of Lithium?” in the New York Times Nassir Ghaemi and colleagues review the evidence on trace lithium and suicide, homicide, crime, and dementia A recent study casting doubt on the trace lithium/suicide prevention link Jesse Hicks explains the fluoride controversy for the Science History Institute Jesse Hicks explains trace lithium, for Vice More of Vox’s effective altruism coverage ––– Discover more podcasts from Vox here.  Learn more about your ad choices. Visit podcastchoices.com/adchoices