In recent years, there has been an onslaught of advertisements trying to convince men to take hormone replacement to treat low levels of testosterone, or “low T.” The ads will ask things like: “Are you suffering from any of the following: , low energy, weight gain, fatigue, low drive?”

“Those symptoms are true of everybody as they age, to a greater or lesser extent,” says Glenn Braunstein, an endocrinologist and vice president of clinical at Cedars-Sinai Medical Center in Los Angeles. He says, "Low T is the latest trend in direct-to-consumer , promoting such products as AndroGel, Testim and Axiron that deliver the male sex hormone through the skin — a more convenient and less painful option than the injections that have been available for decades."

False advertising may suggest that testosterone can alleviate depression, improve mood, boost sexual performance, increase energy, help you lose weight... Although these conditions can all be symptoms of too little testosterone — they can also be treated by a wide range of healthier lifestyle choices. Hormone experts say that using testosterone as a quick fix for aging may be misguided and in some cases unsafe. Any type of hormone replacement therapy is going to have potentially dangerous side effects.

Testosterone’s Dual-Edged Sword

In a paper titled, “Testosterone Inhibits Trust but Promotes Reciprocity” researchers at the Rotterdam School of Management report that testosterone is implicated in behaviors that help to foster and maintain social relationships, indicating that its effects are more nuanced than previously thought. The findings were published in Psychological Science, a journal of the Association for Psychological Science.

Animal studies have shown that testosterone plays a role in dominant social behavior. In humans, previous studies have linked testosterone to dominance and competitive success in when men battle one another for a sexual partner. Interestingly, once the competition for a mate is secure, testosterone seems to flip and boost a fierce need to "tend-and-befriend," much like oxytocin.

In terms of the evolutionary role of a dominant male in a group, Boksem and colleagues reasoned that testosterone in humans would also increase a drive for social status. If you imagine an alpha male in a group of hunters and gatherers, one would expect the role and maintenance of high social status to include both fighting off competition and protecting the group. The same would be true for any person in a corporate management position or family.

"Testosterone may mediate competitive and potentially antisocial behavior when social challenges or threats need to be confronted and handled," explains lead researcher Maarten Boksem of Rotterdam School of Management, Erasmus University (RSM) in the Netherlands. "But it can also induce prosocial behavior in the absence of these threats, when high status and good reputation are best served by positive behavior. But we doubted that this drive would automatically result in aggressive and antisocial behaviors," says Boksem. "We hypothesized that testosterone could perhaps also lead to prosocial behavior if such behavior would be beneficial for maintaining or obtaining social status."

To test this hypothesis, the researchers had 54 female volunteers ingest a liquid solution several hours before participating in an investing game. Some volunteers were given a solution while others received a solution with testosterone.

In the investing game, participants were given about $30 and were instructed that they could keep the amount they wanted and invest whatever remained with a trustee (another participant). The invested portion would be tripled and split by the trustee, who would keep whatever portion she wanted and return the rest to the investor.

If participants were completely trusting, they could invest all $30 and hope that the trustee would split the final $90 equally. If they wanted to play it safe, they could keep the $30 for themselves. Each participant took turns playing both investor and trustee. When they were the trustee, they were always given $90, indicating that the investor had entrusted them with the task of splitting up the whole sum.

As investors, participants who received testosterone were, on average, stingier—they placed less trust in the trustee and kept more of their initial money. Participants who received the placebo, on the other hand, were more trusting investors, choosing to invest about $5 more than those who received testosterone.

Just as the researchers predicted, testosterone seemed to promote antisocial behavior in response to a potential threat—in this case, a threat to financial resources. But the opposite effect emerged when participants played the role of trustee. In this case, participants given testosterone chose to give more money back to the investor than participants who had been given a placebo. The results suggest that the trustees felt a responsibility to literally repay the trust that the investor had placed in them.

Testosterone and the Mating Game

According to Richard Slatcher, Ph.D., assistant professor of psychology in Wayne State University's College of Liberal Arts and Sciences the effects of testosterone on dominance behaviors were especially pronounced among men who reported having a high need for social dominance.

In a 2011 study, "Testosterone and Self-Reported Dominance Interact to Influence Human Mating Behavior," published in the journal, Social Psychological and Science, these men showed a strong positive association between their own testosterone and their own dominance behaviors and, most surprisingly, a strong negative association between their own testosterone and their opponents' dominance behaviors.

Men both high in testosterone and those who reported a high need for social dominance appeared able to beat out their competitors' ability to attract potential mates. However, when men reported a low need for social dominance, they were still able to attract women and there was zero association between testosterone and successful mating behavior.

"We found that testosterone levels influenced men's dominance behaviors during the competitions, how much they derogated (or 'bashed') their competitors afterward, and how much the woman said she 'clicked' with them," said Slatcher. He concludes, “These findings highlight an important difference between humans and animals. In humans-unlike animals-explicit, conscious motives can affect how a hormone such as testosterone shapes behavior."

"Books, film and television often portray men who are bold and self-assured with women as being high in testosterone," Slatcher says. "Our results suggest that there is a kernel of truth to this stereotype, that naturally circulating testosterone indeed is associated with men's behaviors when they try to woo women."

Conclusion: Testosterone magnifies both prosocial and antisocial behavior.

"While we expected the decrease in trust, the increase in reciprocity was surprisingly strong and robust," Boksem concluded. "Testosterone had a more pronounced effect on prosocial behavior than on antisocial behavior."

“The fact that testosterone can promote prosocial behavior, at least in certain contexts, provides a more nuanced account than the traditional view of testosterone as being involved in purely aggressive and antisocial behavior,” says Boksem. The researchers hope to run a similar study in men and they are currently investigating additional types of social behavior under various conditions of social threat.