While high levels of testosterone are often associated with aggression and macho posturing, new research has found it also increases honesty among men.
According to new findings from a team of researchers at the University of Bonn, Germany, testosterone improves social behaviour.
Testosterone is present in both men and women, but is much more prevalent in males. It forms sexual characteristics and increases libido and muscle building.
The researchers had male subjects participate in a basic game of dice-rolling, for money. Some had been treated with testosterone, while others had received a placebo.
The two groups were split into separate booths. The higher their scores, the more money they received.
Prof Bernd Weber, a neuroscientist from the Centre for Economics and Neuroscience at the University of Bonn, said: "These experiments were designed such that the test subjects were able to lie. Due to the separate booths, nobody knew whether they were entering their real scores into the computer, or higher ones in order to get more money."
While the scientists did not know who had been given testosterone, they were able to determine who had cheated. "Statistically, the probability for all numbers on the dice to occur is identical," Weber said.
"So, if there are outliers in the higher numbers, this is a clear indication that subjects have been cheating."
After comparing the results, the researchers found those with high levels of testosterone had lied far less than those who had been given the placebo.
Professor Armin Falk, a colleague of Weber, explained that the probable reason for the increased honesty was because testosterone increased pride and the need to develop a positive self-image.
He said: "This result clearly contradicts the one-dimensional approach that testosterone results in anti-social behaviour. A few euros are obviously not a sufficient incentive to jeopardise one's feeling of self-worth."