Do new fathers have lower testosterone than single men?

Author's Note: Do new fathers have lower testosterone than single men?

Lee T. Gettler's study finding that fathers appear to have lower average testosterone levels than single men was one of the most headline-making scientific discoveries of 2011. International news services and publications interpreted the data at will, typically drawing conclusions that lower testosterone correlated to lackluster sex drives and effeminate fathers without merit. Which is a major reason I was motivated to write this article. Taking time to read the entire study as well as interviews with the lead researcher Gettler quickly revealed massive scientific misinterpretation among the media. The notion that men might possess evolved mechanisms for care-giving, like women, doesn't make them any less male. Rather, it helps explain why fathering has such a salient impact on children.

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