A study by Memorial University of Newfoundland in Canada was conducted to determine whether men really do experience flu worse than women or whether it is just a myth.
Dr Kyle Sue, a clinical assistant professor at the university, suggested men may not be exaggerating symptoms but have weaker immune responses to viral respiratory viruses.
Dr Sue analysed relevant research and found evidence that adult men have a higher risk of hospital admission and higher rates of deaths associated with flu compared with women, regardless of underlying disease.
Men are also more susceptible to complications and higher mortality from many acute respiratory diseases.
Some evidence supported men suffering more from viral respiratory illness than women because they have a less robust immune system.
Writing in the British Medical Journal, Dr Sue argued the concept of "man flu" is potentially unjust and further research is needed.
"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 writes.
He said a less robust immune system might actually have an evolutionary benefit, as it has allowed men to invest their energy in other biological processes, "such as growth, secondary sex characteristics and reproduction".
"There are benefits to energy conservation when ill," says Dr Sue.
He added: "Lying on the couch, not getting out of bed, or receiving assistance with activities of daily living could also be evolutionary behaviours that protect against predators.
"Perhaps now is the time for male friendly spaces, equipped with enormous televisions and reclining chairs, to be set up where men can recover from the debilitating effects of man flu in safety and comfort."