A Cambridge academic, trying to analyse economic decisions made by stock market traders, claims that testosterone and cortisol associated with high stress levels clouded the judgment of men on big-money deals.
Research by John Coates, a Wall Street trader turned neuroscientist, suggested that stocks dealing could be more successful if there were more women on the trading floors.
He claims the root of the global financial crisis, US sub-prime mortgages given to people who could not afford to repay them, might not have been so widespread had there been more women holding top positions in world banking.
Coates told media the traders he tested were caught in "feedback loops" where levels of the chemicals, along with confidence and appetite for risk, rose so high they affected their judgment.
Saliva swabs taken from traders showed that at some point the levels reached a point where men became over-confident and took bad risks.
"If it is true that this testosterone feedback loop is exaggerating bubbles then it is possible that bubbles are a male phenomenon. Women have only 10 per cent of the testosterone men have and older men have less than younger men. The trading world is 95 per cent young males.
If there were more women and older men there might be more stability," Coates was quoted as saying by media.
Trying to understand people's economic decisions, Coates compared it to bulls, animals which lend their name to fast-growing markets, and enjoy runs of growing confidence as they beat off rivals. Each time they win a fight, he said, they get more aggressive, taking bigger risks until they lose.