Men may actually have weaker immune responses than women.
If you’ve ever noticed that men seem to whine about being sick far more than women do, you’re not alone. There’s even a word for the male tendency to exaggerate their suffering: “man flu.”
But are men really exaggerating, or might their experience of being sick actually feel worse than it does for women? Dr. Kyle Sue, a family medicine professor at Memorial University of Newfoundland in Canada, wanted to find out, so he pored over as much sex-related flu research as he could find. His review was published Monday in the famously cheeky Christmas issue of the BMJ—and though it doesn’t present any new findings, it’s likely to make men feel pretty smug about feeling sick.
Based on the existing research, Sue concluded that the man flu moniker is “potentially unjust,” citing studies that suggest men are not exaggerating their symptoms, but instead truly have weaker immune responses than women.
A number of studies conducted in mice or human cell samples suggest that differences in male and female sex and stress hormones may affect influenza outcomes, to the benefit of women, Sue writes. However, human studies have been mostly epidemiological: looking at trends and patterns within a population, rather than a controlled experiment within a lab.
Still, these studies and surveys suggest that men with influenza are more likely than women with influenza to die or need hospitalization; that women tend to be more responsive to flu vaccines than men; and that men self-report taking longer to recover from viral respiratory illnesses than women, Sue writes.
Some studies, he adds, have also suggested that testosterone may suppress the immune system, pointing to a potential evolutionary basis for man flu. Strength and virility were once more important than immunity for testosterone-charged men, he writes, who were likely “to die from trauma before an infection kills them.” By that logic, man flu could even be a defense mechanism, keeping weakened men laid up and away from predators and competitors during the recovery process.
There are major limitations to these studies: among them the biases of the author, the low-level quality of some of the evidence and a failure of the review to take into account sex-related behavioral differences. Sue, who acknowledges these barriers, calls for further research to help determine if the phenomenon is truly psychological, or if there’s a physiological basis to man flu.