Women less trusting when taking testosterone

May 25, 2010 by Lin Edwards report

(PhysOrg.com) -- New research suggests women become less trusting, less open, more vigilant, and more skeptical and cynical if they are given the male hormone testosterone. This may reflect the survival value for women of being sociable and co-operative, whereas males have historically needed to fight competitors for resources if they were to survive.

The hormone makes men stronger, larger, and more aggressive, and the new research suggests it also makes them less open and more distrustful, “watching their backs” for dangers. While testosterone is often called the male sex hormone, it is also present in women, but in smaller amounts.

Psychologist Dr Jack van Honk gave either a or the to a group of 24 women with an average age of 20, and then switched pills, so all the women were given both the testosterone and the placebo. The women were asked to rate 150 photographs of strangers’ faces for , using a scale of +100 (most trustworthy) to -100 (least trustworthy) when they were taking the placebo, and when they were given the hormone.

The research found that women who were most trusting on the placebo rated faces as around 5 percent less trustworthy while taking the hormone pills. Women who were least trusting on the placebo did not appear to be affected, and van Honk speculated this might be because in less trusting individuals the hormone could make them paranoid and socially disabled.

The results also showed the natural level of testosterone in the women had no effect, and their mood also had no effect. The researchers said there was no evidence the knew when they were taking testosterone.

The authors of the paper, published in the journal , say the research shows how testosterone regulates human sociability because it “down-regulates interpersonal trust in an adaptive manner.”

Dr van Honk said you have to be “socially sharp” to be successful in competition, and it is not socially sharp to trust people you do not know. He also said testosterone may increase the production of the hormone vasopressin, which has been shown to increase territorial behavior and aggression in animals, although he said social dominance in humans is not about aggression. It could also oppose the hormone oxytocin, which has been implicated in trust and social bonding.

Dr van Honk said being wary of strangers or competitors is an important part of “rising through the ranks” in humans, and being less trusting could also give economic benefits. He said he could also see applications of testosterone in treating psychiatric disorders such as social anxiety disorder.

Explore further: Early exposure to antidepressants affects adult anxiety and serotonin transmission

More information: Testosterone decreases trust in socially naďve humans, PNAS, Published online before print May 24, 2010, doi: 10.1073/pnas.0911700107

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User comments : 5

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tkjtkj
not rated yet May 25, 2010
He said he could also see applications of testosterone in treating psychiatric disorders such as social anxiety disorder.

Now, forgive me , but that makes no sense at all! How do you expect people who are already 'anxious' to respond to being given a substance that DEcreases 'sociability???

LKD
not rated yet May 25, 2010
I can see this helping people who are too trusting, but the effect seems marginal at best. I am certain that the side effects of testosterone far exceeds the benefit of this study.
Skeptic_Heretic
5 / 5 (1) May 25, 2010
Now, forgive me , but that makes no sense at all! How do you expect people who are already 'anxious' to respond to being given a substance that DEcreases 'sociability???
Testosterone doesn't decrease sociability. I'm not sure where that statement came from.

Minor doses of testosterone, typically used to bring people to relatively normal levels when compared to baseline exhibit stronger social independence, stemming anxiety in most cases. I do agree with you and LKD that it's too early to suggest any form of regime or treatment scope to hormone therapy involving testosterone outside of hypogonadism in men.
mysticshakra
not rated yet May 25, 2010
Wow, another studying confirming what we already knew.
Amy2010
not rated yet May 26, 2010
My question is why would a woman want testosterone when we can see what it does to the males and also given the fact that we castrate bulls, dogs and hogs and other male animals to keep their aggression down.

On top of that I have heard about testosterone poisoning but I have never heard about women being poisoned by our hormones. Just some more of the many advantages of being a woman and not a male.

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