by John Hoffman

I was writing about fatherhood when some of the first studies about dads and hormones came out in the late 1990s. Lots of research had been done on mothers and hormones, but not dads. In the last 20+ years quite a bit of research has been done on fathers and hormones. Much has been learned. But for me, all the findings boil down to one key message for dads.

What you do as a father affects your hormones more than your hormones affect what you do as a father. In other words, if you want and need to be a hands-on dad, put in the time and effort. Your hormones will support and reward you.

At risk of lapsing into a nerdy academic reporting of “the research literature,” I want to share a few particularly interesting findings that support my argument.

One hormone that affects parenting is cortisol. Cortisol is an important stress hormone. It helps us be alert and mobilized to face threats and other stresses. So, it won’t surprise anyone to hear that new dads (and moms, of course) often have high cortisol levels. In some ways this probably helps us meet the challenges of new parenthood (but you don’t want to have high levels of cortisol all the time.)

Well, it turns out that while babies contribute to parenting stress, they can also help us recover. One study found that new fathers’ cortisol levels were, in most cases, reduced after they held their newborn babies. So these stressed new dads felt a little better after the nice experience of holding their little bundle. That fits with other things I know from life experience. Being together with your child and interacting in ways you feel good about, helps you feel good about being father. And feeling good about being a dad helps you be a good dad.

Here’s another really interesting finding. Reseachers wanted to find out how oxytocin, often called the “love hormone,” worked in two groups of dads—primary caregivers (gay fathers, in this study) and secondary caregiver dads who were in heterosexual relationships. They measured the men’s oxytocin levels after dad-baby interaction. But, and this is the cool part, they also used brain imaging to see which parts of the brain were active during the interactions and also to see where the oxytocin was going in the brain. Dads who were primary caregivers were using somewhat different brain pathways than secondary caregivers. And the body sent the oxytocin to brain areas involved in the different types of activity the fathers brains were engaged in. Like, the hormone knew where they needed to go to support what each men was trying to do in his role as a father.

Two more findings. Men who slept in the same bed as their babies (and the mom, no doubt), which is very common in many cultures around the world, had lower levels of testosterone than dads who slept separately from their babies. Testosterone tends to support things like competition for a mate or the urge to procreate. Reduced testosterone tends to help fathers be more involved in caregiving.

And lastly, in another study, which was one of the first I heard about, dads with hands-on experience had bigger releases of prolactin in response to hearing a recording of a crying baby. Prolactin is another hormone that supports nurturing behaviour. In other words these guys’ hormone activity changed because of their caregiving experience.

So, as you can see, what you do as a father changes the way your body responds with hormones. And that supports one of the first conclusions I ever drew about involved fatherhood, thirty-odd years ago: involved fathering is a self-fulfilling prophecy. The more you get involved, the more you’ll get good at it and want to keep doing it. And your hormones will help you.