Man flu: man-made or real illness?
Sex-linked hormones, such as estrogen, might be associated with changes in immune response.
The concept of “man flu” may be viewed from a new perspective, as men may actually have weaker immunity to certain illnesses than women, according to a feature in the BMJ.
Kyle Sue, MS, a clinical assistant professor in family medicine at the Health Sciences Centre, Memorial University of Newfoundland in Canada, wanted to uncover the truth about “man flu” and its relation to the male immune system.
Mr Sue researched several gender-related immunologic studies to determine if there were any similarities between sex and immune response. In one study, researchers observed that female mice had higher immune responses compared with their male counterparts.
This inspired the author to question if sex-linked hormones may be directly involved with immune response. Two hormones, estradiol and corticosterone, were noted in the studies to be associated with an increase in immunity in the female mice.
In another study, nasal epithelial cell cultures were extracted from men and women and infected in vitro with a seasonal influenza A virus while exposed to estradiol or select estrogen receptor modulators. The epithelial cells from female donors ended up with lower viral concentrations than male donor cells.
A separate study used a rhinovirus inoculation on mononuclear cells from men and women of the same age groups. Of the subjects in the study, cells from pre-menopausal women had a more robust immune response, while men and post-menopausal women had weaker immunity.
According to Mr Sue, studies have labeled estradiol as immunoprotective and testosterone as immunosuppressive, but not much other research has been conducted on other aspects of health between genders. For instance, on a global level, men have higher smoking rates, while women are more likely to seek assistance when ill. Environmental conditions, secondary sexual characteristics, and other variables have still not yet been studied at a more complex level.
“The concept of man flu, as commonly defined, is potentially unjust,” stated Mr Sue. “Further higher quality research is needed to clarify other aspects of man flu.”
- Kyle S. The science behind “man flu.” BMJ. 2017 Dec 11. doi: 10.1136/bmj.j5560