Man flu is not a myth: Female hormones give women stronger immune systems



Men's ability to turn a sniffle into flu and a headache into a migraine has long been a source of irritation to wives and girlfriends.

But man flu may not be a myth after all thanks to research showing that men really are the weaker sex.

Researchers found that women have a more powerful immune system than men thanks to their hormones.

Weaker sex: Research on mice found females are protected by the hormone oestrogen which boosts the immune system's first line of attack on bacteria

The study showed that the female sex hormone oestrogen boosts the immune system's first line of attack against bacteria and other invaders.

The finding raises the possibility of using oestrogen-based drugs to shore up the male body's defences.

The research focused on an enzyme called caspase-12.

It raises susceptibility to infection by blocking the inflammation the body uses to fight bacteria and other unwanted bugs.

Mice unable to make the enzyme were extremely resistant to infection, the researchers from McGill University in Montreal showed.

They then genetically engineered the mice to make the enzyme. The males became susceptible to infection, as expected, but the females didn't.

Experiments showed that the oestrogen made by the female mice kept immunity high, the journal Proceedings of the National Academy of Sciences reports.

Researcher Maya Saleh said: 'These results demonstrate that women have a more powerful inflammatory response than men.'

She added that while the study was carried out on mice, the finding was likely to apply to people, raising the possibility of immunityboosting drugs.

But Dr Saleh cautioned: 'A question remains. Will men be amenable to the idea of being treated with an exclusively female hormone?' Surveys have shown that up to 30 per cent of men take sick days because of colds and flu, compared with just 22 per cent of women.



Dr Saleh said studies had shown that men are more susceptible than women to infection by bacteria, viruses, fungi and worms.

It is thought the phenomenon has its roots deep in evolution, with healthy female bodies being key to reproduction.

The researcher said: 'We think that nature devised this strategy to protect the reproductive role of

the female body, to keep the human race going. It just dropped the mechanism from the male sex.'

Previous research has revealed why some people can cope with pain, while others turn to the medicine cabinet at the first hint of a headache.

Scientists from Stanford University in California concluded that the difference between them is simply one of mind over matter.

They said pain can be blocked out or reduced by telling yourself it does not exist.

We can train our brains to switch on and off feelings of pain, the researchers believe.

Visualisation techniques, including imagining falling snowflakes easing pain away, can reduce the discomfort of chronic back pain by two-thirds, they added.