When you hear the word "testosterone", you probably picture a strong, tough, manly man, right? But in the fight against the flu, it turns out the hormone actually makes men weaker.
Researchers at Stanford University analyzed blood samples from nearly 90 adults who had just received the seasonal flu shot. What they found would make men all over the world want to quarantine themselves until the end of flu season. It turns out that men, specifically those with the highest testosterone levels, had a weaker response to the flu vaccine than women. Men with low testosterone levels, on the other hand, had an antibody response similar to that of women. The study was published in the Proceedings of the National Academy of Sciences.
Why Testosterone Hinders the Flu Shot
Researchers founds that testosterone -- the hormone that fuels men’s sex drive, beard growth and muscle development -- causes genes in the immune system to produce fewer antibodies in response to the flu shot. And the higher testosterone a guy has, the lower his antibodies (and immune protection) are. That makes the vaccine less effective, thus increasing a guy’s chance of coming down with the flu.
And it gets worse, fellas: It’s known that men also don’t respond as well as women to several other vaccines, such as hepatitis and measles, and their overall weaker immune systems make them more susceptible to all types of infections.
How to Stay Flu-Free
Experts are divided about what the findings mean for your annual flu shot. It’s possible that men could receive a higher dosage in the future. To make sure you beat the flu this season, don’t skip the shot—it’s still your best defense—and follow these stay-healthy tips: