Because it was in the 1950's or so, maybe the late 1940's, that people started to discover lithium, even though it had no natural function, it did do something in our bodies.

因为在二十世纪五十年代左右，可能是四十年代末期，人们开始发现锂，尽管不参与人体的正常生理活动，但是它确实会对我们的身体产生影响。

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But people died typically of either infectious diseases or they died during childbirth, or they might have died at old age which would have been 50 or so at that time.

那时的人要么死于传染病,要么在分娩的过程中死去,或者在他们大约五十岁左右的时候,死于衰老

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