Hormones are the signals that orchestrate every aspect of our life: from our linguistic abilities to our aggression levels, and from how we fall in love to how we age. To learn more about how hormones affect us, we spoke with New York-based Psychology Professor and hormone researcher Dr. Adar Eisenbruch who will be doing a talk next Monday on The Chemistry of Chemistry at Subject in the Lower East Side (click here for details).
Dr. Eisenbruch earned his PhD in Psychological and Brain Sciences from the University of California, Santa Barbara, before completing his postdoctoral fellowship in the Evolutionary Psychology Laboratory at Harvard University. He’s currently a Visiting Assistant Professor in the Psychology Department at SUNY Purchase, in upstate New York.
We asked Dr. Eisenbruch about why he thinks testosterone levels in men have been declining, the role of hormones in love, and his thoughts on the benefits and risks of hormone therapy…
Your upcoming talk on “The Chemistry of Chemistry” is all about how hormones impact our decisions. What is the most surprising thing you’ve discovered so far in your research on this topic?
One of my studies found that women’s likelihood of wearing red (which may be a courtship signal) was predicted by their ovarian hormones on that day. Part of what I find really interesting about this is that it shows that hormones are involved not only in the big, obvious stuff — like falling in love — but also in the tiny, quotidian decisions that we barely even notice. Some other studies have found the same effect and others haven’t, so part of the lesson here may also be on how science like this progresses.
Studies have shown that men’s testosterone levels have been declining for decades. There’s no clear-cut answer as to why. Do you have any theories on this? And what, for you, is the most positive and the most negative impact that these declining testosterone levels may have on men and society as a whole?
This is a great, tough question. The short answer is I don’t know. Speculatively, testosterone may be declining because of (among other things) changes in nutrition, environmental conditions, and lifestyle. Physical competition often elicits testosterone increases, so if men are becoming more sedentary (e.g. fewer pick-up basketball games, more sudoku), that could explain some of the decrease. There’s evidence that people are having less sex these days, which could plausibly be both a cause and an effect of declining testosterone. Positive and negative impacts might be in the eye of the beholder; how burly, risk-seeking, and violent do you like your men? One thing to keep in mind is that young men in places like the US have extremely high testosterone compared to young men in subsistence societies, so the decline in testosterone here might be more of a return to normal. The big story might not be why is testosterone going down, but why was it so weirdly high in the first place?
Hormones play a huge role in our mating behavior: “happy hormones” like dopamine help us fall in love, and attachment hormones like oxytocin help us form pair bonds to ensure the survival of our young…but can both hormones be sustained, over time? Can hormones make it possible to maintain those romantic feelings over time, or are we doomed to keep seeking the next dopamine fix?
There’s evidence that hormones can affect memory formation, so the effects of elevated hormones can outlast the hormone elevations themselves. Also keep in mind that these hormones wax and wane constantly. It’s not the case that oxytocin shows up at the formation of a pair bond and is never seen again. There’s lots that people do without even trying that causes increases in oxytocin and dopamine, so I think hormones definitely help with sustaining relationships, not just forming them. Also, I’m not sure it’s so terrible to keep chasing the next dopamine fix. If people get a dopamine surge from seeing their partner succeed or their child graduate from high school, that seems like a good thing.
How big of a role does cortisol – often referred to as the stress hormone – play in determining our well-being and what can we do to decrease it?
Cortisol isn’t really a stress hormone — it’s an arousal hormone. It goes up in response to many stressful situations, but also in response to other situations that people might actually enjoy, like talking to an attractive potential mate. So I don’t think we should focus on decreasing cortisol for its own sake, but we should try to understand what elicits it, what effects it has, when elevated cortisol is useful, and when it may be harmful. People may want to try to reduce their cortisol levels, but the problem isn’t cortisol itself so much as the conditions that cause chronically elevated cortisol.
Hormone therapy is being used to treat all kinds of issues, from menopause to building muscles. What are the biggest promises – and the biggest dangers – of hormone therapy?
I’m not a clinician, but it seems like hormone therapy has a lot of promise for improving people’s lives, and the more we know about how the body adaptively regulates itself and responds to situations, the more we can develop effective, safe interventions. I think there are a couple of big risks here. The first is thinking about hormones as static. Hormones like estradiol and testosterone fluctuate day-to-day, even hour-to-hour. In part, this is because the body produces hormones in response to specific situations. Interventions that give people a relatively fixed hormone concentration might cause them to have too much in one situation, and too little in another.
The second is thinking that we should all have the hormonal profile of a 25-year-old. A lot of hormone therapy seems targeted towards aging, in one way or another. Part of what I’ll talk about on Monday is how hormones track social motivations, and from an evolutionary perspective, it makes sense for people’s priorities to shift over the lifespan. For example, grandparental care was very important to our ancestors; declining sex drive as people age and spend more time caring for grandchildren may be a feature, not a bug. People may have different goals and desires now, but I’m wary of pathologizing normal aging.
Meet Professor Adar Eisenbruch this Monday night (October 21st at Subject in NYC) for a talk on The Chemistry of Chemistry: How Hormones Affect Romance and Relationships. Details here.