Brains, Bodies, and Symbiosis

Brains, Bodies, and Symbiosis

Until quite recently, I've always been Hygeia's darling, particularly when it comes to digestive health. The usual problems of that kind were things I merely heard about in other people's lives. Unfortunately, it seems I have now developed an auto-immune disorder associated with digestive difficulties, which luckily is well-controlled with not-outrageously-priced medication. The whole experience has piqued my interest in what all those gazillions of gut flora are up to in there.

The most recent article to catch my eye was on my newly discovered favorite site, Not Exactly Rocket Science. People are publishing interesting articles about the role of gut flora not only in digestion but in the immune response and even mood. One study found that

mice, after regularly eating Lactobacillus, were more likely to spend time in the exposed parts of a maze (a common test for anxiety symptoms) than those who ate bacteria-free meals. They were also less likely to drift motionlessly when plopped into water (a common test for depressive symptoms).

I'm eating a lot of yogurt myself now, and am wondering whether I would behave differently if plopped down into the middle of a maze, or a deep body of water. Speaking of which, does it seem like a good idea to send National Guardsmen into deep water if they can't swim? I thought at first it was a matter of heavy clothing and boots, but this fellow's companion swam after him like a champ once he started going down. That looked dicey.



Back to gut flora and mood: evidently it's the vagus nerve, connecting the gut to the brain, that transmits the influence. Sever the vagus nerve in mice, and their guts no longer affect their behavior.

Some speculate that we eventually will learn how to treat mood disorders with probiotics. All I know is that they seem to work well on my gut. Some combination of the medication I'm now on, and the probiotics, certainly have eliminated the chronic fatigue that dogged me all last spring: gone like flipping a light switch. Of course, it may just be that the intestinal inflammation is controlled and I'm absorbing nutrients better. Still, even my somewhat skeptical gastroenterologist believes there's some good clinical evidence implicating gut flora imbalances in flare-ups of this condition. I guess I'll take my chances with the probiotics for the time being, especially since it's pretty clear they can't hurt me.

So my small passengers and I seem to do each other considerable good, and we do well to keep each other in a happy mood.