Why men are more predisposed to infections
A group of American scientists from the Howard Hughes Medical Institute in the United States, headed by Mark Davis, has found out that men are suffering from infectious diseases, such as the flu, much more often than women and the reason of this phenomenon lies in the testosterone hormone.
Testosterone is the primary male sex hormone, androgen. This hormone is secreted by Leydig cells of the testes in men, and (in small quantities) by the ovaries in women, as well as the adrenal cortex in both sexes. It takes part in development of male reproductive organs, secondary sexual structures, and regulates spermatogenesis, also influences nitrogenous and phosphorous metabolism. The more testosterone the man or woman has, the more masculine appearance he or she has.
The study was carried out in 2008-2009, it included 53 female and 34 male participants; there were representatives of age groups of 20-30 years and 60-89 years. In the course of the study the researchers found dependence between the speed of immune response to vaccination and amount of the testosterone.
Immune response is the protective mechanism enabled by our immune system that helps to prevent introduction of foreign harmful macromolecules. It means reaction of the body to such intervention, and the speed of immune response is how quickly the immune resistance system can eliminate the presence of foreign elements in the blood. Suppression, i.e. deceleration or even disabling, of the immune response affects the resistance of the human body to infectious diseases.
Scientists have found out that testosterone suppresses immune response to the flu, which is the reason why men with higher levels of this hormone are much more likely to catch the virus and fall ill than women.
Scientists have also found out that prior to vaccination in men with poor immune response to the infection, high levels of testosterone were observed, and vice versa – men with high immune response to the infection had lower levels of the testosterone hormone.
The results of the study were published in the PNAS periodical. Since the publication a huge amount of work has been done, and the next stage of the medical research will be aimed at how to influence and control the ability of testosterone hormone to suppress the immune response, and, maybe, compensate this phenomenon.