Swearing can relieve pain - but only if you don't curse regularly in everyday life, claim psychologists.
Previous studies have shown that letting fly with a few choice expletives can ease pain.
But the bad news is that the pain relief quickly wears off for habitual swearers, according to Keele University researchers.
Dr Richard Stephens and Claudia Umland asked 71 volunteers aged 18 to 46 to assess how frequently they swore, ranging from hardly ever to 40 times a day or more.
They then had to keep their hands in icy water for as long as possible to test their pain tolerance.
Those who seldom swore were able to stand the icy water for 45 seconds longer when they were swearing than when they were not swearing. But those who often swore gained
only ten extra seconds.
The experiment showed the more often people swear in daily life, the less extra time they could stand the pain.
Dr Stephens said that swearing appeared to induce a 'fight or flight' response that acted as a stress-induced painkiller for those who did not swear regularly.
He said: 'Many people think swearing is only for those with a low IQ or a poor vocabulary but that's far from the case. People have a need to swear, it's a human emotion that can
serve a purpose in life or death situations - if you don't do it too often.'