Men
who become fathers have lower testosterone levels, researchers find.
But that appears to be beneficial in helping to raise children. Having
more testosterone may help men find mates, but fathering children makes
their testosterone levels decrease rapidly – by as much as 25%.
Researchers at Northwestern University and the Philippines studied 624
single men in the Philippines beginning in 2005. Over time, 162 of them
entered into stable relationships and had children. Tests showed that
the fathers’ testosterone levels decreased by an average of 26% during
the day and 34% at night compared to single men. Experts say the study
suggests that men’s bodies evolved hormonal systems that helped them
commit to their families once children were born. It also suggests that
men’s behavior can affect hormonal signals their bodies send, not just
that hormones influence behavior. And it underscores that mothers were
meant to have child care help.
