Flu Vaccine Less Effective on Men With High Testosterone Levels

There might actually be some good news about women's health: research shows that flu shots may be more effective in women than in men. But, it also shows that the flu vaccine may be less effective on men with high testosterone. One study (which, granted, only had 87 participants) showed that the response to the vaccine was weaker in men. In theory this means that women are better protected after getting the shot than the other half of the species. And while this is nothing to celebrate, it's always nice when healthcare practices don't actively work against women.

The difference in responses seems to be related to hormones. Apparently the higher the testosterone levels, the lower the numbers of antibodies produced after receiving the shot. The researchers linked the differences in immune response to a set of genes controlled by testosterone, and speculated that the difference might be evolutionary. The theory goes that males are more likely to experience traumatic injury, so their lowered immune response is a way to protect against sepsis, a potentially fatal over-response of the immune system.

Whatever the underlying reasons, though, one of the study's authors stated that the results demonstrate that there are "major differences" between the male and female immune systems, a difference that hasn't been fully explored by science yet. Well, get on it researchers. Jeez, always falling down on the job.

In all seriousness, though, it is about time that science delve into things like this. I'm the last person to ever support the whole "biological determinism" nonsense, but if different human bodies do things differently, then the more science understands the discrepancies, the better. Because historically, I think we all know who's gotten the short end of the stick in those situations.

If women really are better protected by the flu vaccine, that's awesome for selfish reasons, but the bigger point is that a difference in immune response is kind of a big deal. You know, on account of the immune system being the body's defense system against the millions of bacteria and viruses swirling around out there just waiting to kill us. So hopefully we'll be getting more research on this soon. But in the meantime, you can appreciate your shot even more.

Image: Wikimedia Commons