'Man flu' – the much-debated phenomenon where a man suffering from cold, flu or other minor ailment is regarded as exaggerating his symptoms – may actually have some basis in fact, according to a new study published in the BMJ.

Despite the ubiquity of viral respiratory illnesses, no scientific study has looked into whether the term 'man flu' is appropriate or accurate.

So, in an attempt to shed more light on the topic, Kyle Sue, a clinical assistant professor at Memorial University of Newfoundland in Canada, investigated whether men do indeed experience worse symptoms than women and if this has an evolutionary or biological basis.

Sue reviewed research in the field and found that adult men have a higher rate of hospital admission as well as higher rates of influenza associated deaths compared with women of similar ages, regardless of underlying diseases.

Males are also more susceptible to many acute respiratory diseases and exhibit a higher mortality. Furthermore, there is evidence to suggest that men suffer from more respiratory illnesses than women because they have less robust immune systems.

In light of these findings, Sue thinks the concept of man flu, may be unfair. "Men may not be exaggerating symptoms but have weaker immune responses to viral respiratory viruses, leading to greater morbidity and mortality than seen in women," he said.

And although it may seem counter-intuitive, there may actually be an evolutionary benefit to having a less robust immune system, Sue explained, as it has enabled men to invest more energy in other biological processes such as growth and reproduction.

In addition, conserving energy when ill may have also been beneficial at one time in our evolutionary history. "Lying on the couch, not getting out of bed, or receiving assistance with activities of daily living could also be evolutionary behaviours that once protected against predators," Sue explained.

However, he thinks more research is needed into the phenomenon of man flu because "it remains uncertain whether viral quantities, immune response, symptoms, and recovery time can be affected by environmental conditions".