London: For years, women have cried “man flu” when men make a fuss over a few sniffles.
But a new study suggests that men actually suffer more when they are struck down with flu because high levels of testosterone can weaken their immune response.
The study, by Stanford University School of Medicine, examined the reactions of men and women to vaccination against flu. It found that women generally had a stronger antibody response to the jab than men, giving them better protection against the virus.
Men with lower testosterone levels also had a better immune response, more or less equivalent to that of women. It has long been suggested that men might be more susceptible to bacterial, viral, fungal and parasitic infection than women are.
The study, published in the Proceedings of the National Academy of Sciences, found that women had higher blood levels of signalling proteins that immune cells pass back and forth when the body is under threat.
Anti-inflammatory properties
Previous research has found that testosterone has anti-inflammatory properties, suggesting a possible interaction between the male sex hormone and immune response.
Mark Davis, a professor of microbiology and immunology, said: “This is the first study to show an explicit correlation between testosterone levels, gene expression and immune responsiveness in humans. It could be food for thought to all testosterone-supplement takers.”
Scientists said they were perplexed as to why evolution would design a hormone that enhances classic male sexual characteristics — such as muscle strength, beard growth and risk-taking propensity — yet left them with a weaker immune system.
Previous studies have found that, while women may accuse men of exaggerating when they have flu, females are more likely to admit to having sniffles and sneezes.
