Tuesday, May 19, 2009

photoperiod + swine flu.

I get a nasty cold/flu EVERY year about this time. Which is weird, because I hardly ever get sick in the winter. Since I've been banished from work today (one benefit of working in health care is that they take sick days seriously) I decided to do a little research on the subject.

So I googled this phrase " seasonal immune comprimise" and came up with a bunch of journal articles.

Apparently I am close to my mammilian predecessor the hampster because several studies have shown that hampsters and rats have decreased immune function in the summer(http://icb.oxfordjournals.org/cgi/reprint/38/1/226.pdf).

In brief:
Winters are super stressful for animals. They've got to try to stay warm while surviving on the little bits of food that are left over from the fall. Because they have a minimum amount of food, animals have to maximize their use of energy. Apparantly the sun controls which body functions still get used in the winter and which ones get shut off.
Once the days start getting shorter (less sun), the body starts producing more of the hormone melatonin, which in turn increases the bodies immune function and decreases the production of sex hormones! So that is why most animals don't mate in the winter..........and this must also be why I never get sick in the winter!

When spring rolls around, the animals change gears. There is plenty of food around and they don't have to spend as much energy staying warm - the longer days decrease the amount of melatonin made in the body which in turn decreases immune function and increases sex hormones. Sooooo when the days get longer, animals stop working on immunity and start working on creating posterity..........

I'm pretty sure this research is limited to hampster and rat subjects. But I think that my immune function is affected by the photoperiod (change in day length). Maybe most people aren't affected by this because they usually aren't awake when the sun rises. Or maybe most people aren't affected becuase their bodies carry more than enough energy stores to run all body functions at the same time........who knows................. At any rate, I'm going to take a nap now - take that melatonin.


Jessica and Bronson said...

This is pretty awesome information! Thanks for sharing. It answered a lot of my questions. Bronson has the same problem. :)

Sherpa said...

So many things to tease you about....

But, since I like you--I'll tell you about guinea pigs and hamsters. Mom refused for us to get a hamster when we were little or ever because she had to feed, take care of, and then dissect a guinea pig one semester--and she said hamsters remind her of that guinea pig. That and they look like little rats. She can tell you the whole story, I'm sure. :)

Get feeling better, being sick is no fun.

Richard and Nicole said...

jessica: yeah - i think it affects people that wake up really early

Sherpa: thanks for being nice. i know im a nerd. and i have heard the guinea pig story.........its a good excuse not to have nasty pets.....im with your mom on that one.

Isaac said...

Hmmm, interesting stuff. I wonder if they have any studies about hamsters getting sick right before finals?
No, really, ever since I started school (college) I've pretty got sick in November and then stay quasi sick until May. I must be allergic to melatonin.