Today I heard a fascinating story on the radio about the medical value (or, writ large, the evolutionary purpose) of intestinal worms. Dr. Joel Weinstock was interviewed on a local Los Angeles food show about his work with patients suffering from inflammatory bowel diseases such as colitis and Crohn's disease. When he gives his patients worms on purpose, they get better. Why?
In our germophobic, antibacterial society, intestinal worms have been nearly eliminated. For the most part, American food is dipped in chemicals, irradiated, sprayed within an inch of its life before getting to the supermarket. So it's highly unlikely that we'll see little critters crawling out of our lettuce (as a child I had this experience, and, horrified, showed my father. He explained that meant we had a delicious head of lettuce).
From a medical point of view, Dr. Weinstock explains that our immune systems have two aspects: one which protects us from bad bacteria, viruses, and whatever else might invade our bodies. The second aspect protects us from the first - it regulates our immune system response so that we don't injure ourselves. People with autoimmune disease such as lupus, Crohn's disease and others have lost that regulatory capacity.
So how do worms help? Through many thousands of years, worms evolved the ability to regulate the immune systems of their hosts. That way the immune system won't kick them out. In effect, the worms are an immunosuppressant. For someone with no regulatory capacity of their own, that can be extremely valuable.
The value of clean food and water can't be denied. No one suffering from bacterial dysentery, as many children do in developing countries, will deny that. I don't suggest rubbing your food in the dirt before eating. As in so many areas, it's about balance. Worms, bacteria, and other creepy-crawlies give our immune systems a chance to grow and develop. As I learned from my martial arts teacher, solo practice is well and good, but partnered practice makes your skills increase faster, and competition will grow your understanding and skills by leaps and bounds. So our immune systems, in a sense, are like the guy who has a black belt in karate but has never been in a real fight.
Asked for his opinion on how to keep immune systems healthy, Dr. Weinstock said
Let your children play in the dirt. They don't have to wash their hands all the time. And get two dogs and a cat.
You listen to the full interview by downloading or streaming the program at KCRW.com/goodfood. Scroll down for the program for August 2nd. Dr. Weinstock's interview is in roughly the middle of the program. You can also read this New York Times article on the same subject.