Coffee knocks out women's pain

However, the caffeine jolt does nothing to help men, according to their research.

It has long been suggested that women are the harder sex when it comes to dealing with pain, with their ability to cope with childbirth cited as principal evidence for this.

That, however, could be a myth, suggest the researchers, at Goldsmiths College.

Men were, on the whole, better able to withstand pain than women.

Icy ordeal

The experiment used 50 men and women, who were asked to plunge their arms into buckets of ice-cold water and keep them there for as long as they could.

On the whole, men could keep their arms submerged for longer than women.

Psychological studies have suggested that men tend to focus on their senses during pain, while women have a far more emotional response, making it harder for them to cope.

However, when the women were given 250mg of caffeine - equivalent to a double espresso, their tolerance improved.

Afterwards, they were able to keep their arms in the bucket for significantly longer.

Ed Keogh, who led the study, said that increased blood pressure, a side-effect of consuming caffeine, might be behind the improvement.

But there was no explanation as to why men fared no better after their caffeine fix.

He told the London Evening Standard: "The effect may not last for very long, but a quick double espresso probably would make the pain of something like leg-waxing more bearable.

"We need a lot more research into the differences between the genders when it comes to pain.

"It may be that painkillers need to be tailored differently to the sexes to ensure they are as effective as possible."

Caffeine is already included as an ingredient in some painkilling tablets - but only in relatively small doses.