Thanks to Aaron Blaisdell, Alex Chernavsky and Navanit Arakeri.
When I taught Introductory Psychology, I came across a study in which researchers put people in a room with food and watched them. They were looking for cycles in eating and drinking. They noticed that their subjects spent a lot of time touching the face near their mouth — what they called “the snout area”. After I read that, I noticed the same thing countless times. Right now I am at an airport waiting for a flight. Looking around, I see three of about 50 people touching their mouth or nearby.
Why do we do this? I propose an evolutionary explanation: To expose our immune system to all the germs near us in small amounts. Mouth-touching is part of a larger sampling process: 1. We touch many things constantly. In particular, we shake hands, hug, and otherwise touch people near us. Germs that have managed to live in or on other people are the most dangerous. 2. We lick our lips often, moving germs on our lips inside our mouths. 3. When you eat, food transfers bacteria from the inside of your mouth to your tonsils, which circle your throat. Tonsils are full of lymphocytes, the immune-system cells that detect germs. Once we have developed antibodies to a microbe, of course, we are much less vulnerable to it. The whole sampling process is a kind of self-vaccination.
We need conventional vaccination when self-vaccination fails. Polio vaccination was the first big vaccination program, and it worked: polio was nearly wiped out. Before around 1900, polio was not a big problem. It became a big problem at roughly the same time that public health measures and the replacement of horses by cars caused cities to become much cleaner places. Others have theorized that this is why polio became a big problem. As recently as 1951, thousands of children died from polio.
This is related to but different than my ideas about our need for fermented food. (I believe we need to eat plenty of fermented food, day after day, to be healthy.) When we eat fermented food, we ingest large amounts of bacteria that are familiar and safe. The amount is large because the food has been fermented. The bacteria are familiar because we eat the same food repeatedly. They are safe because the insides of our bodies are dramatically different than what we eat (e.g., different temperature). The sampling system I am proposing here exposes us to small amounts of unfamiliar dangerous bacteria. However, this sampling system and the factors that push us to eat fermented food (our liking for complex, sour, and umami flavors) both act to produce the best environment for our immune system. Fermented food resembles exercise and practice; the mouth-touching system resembles information.
A similar sampling system is our love of gossip. We love to hear it, we love to spread it. Gossip spreads information about the dangers around us. Again, forewarned is forearmed.
I am in Tokyo (for a few more minutes), an admirably clean city. Public rest rooms, for example, are convenient, clean, and free. (Unlike New York, Los Angeles, San Francisco, Beijing . . . ) The practical point of this idea isn’t that there is something wrong with public health measures, it is that they can go too far.
Thanks to Robin Barooah and Mike Bowerman.
Dennis Murrell calls himself a “natural beekeeper”. This is one reason he sprayed kombucha on his bees:
In the early spring, I grade my hives strong, average, below average, weak. This year, I sprayed the below average hives with a slightly diluted, about 30%, solution of overly ripe kombucha. It was probably about 3 weeks old. The spraying was done incidentally, without any planning, etc., just to watch the first reaction of the bees. After spraying, the below average hives were left alone, without any more manipulation or observations. . . . Ten weeks later, I popped the covers off the below average hives and found they had a full super of honey, while all the others, even those with larger bee populations had none. I was quite surprised to say the least! And I’d had forgotten about the incidental kombucha spraying until looking at my notes a week later.
Wow. Does this presage a honey surplus? As other beekeepers follow his example? He sprayed kombucha on his bees partly because he himself had found it so beneficial:
I began drinking about a cup a day. . . . I’d been afflicted with a skin aliment since my youth [psoriasis?]. There’s no known cure. Modern medicine can relieve the symptoms. But the drugs used have more long term side effects that are worse than any benefits. Well, within 24 hours [of drinking kombucha], the itching associated with the irritated skin disappeared. Within three days, the slight swelling associated with the irritated skin also disappeared. Within a month, 99% of the irritated areas disappeared. During that time, I lost joint pain that had plagued me for a decade, commercial beekeeping is rough on the back and joints. I regained full movement in my right shoulder. And a sense of wellness replaced whatever biologically stressed out condition I thought was normal. Once you’re over 50, some of the things lost along the way become more apparent. Hair texture, intestinal fortitude, urinary function, energy level, and sexual prowess all decrease. And weight increases. Using kombucha, a probiotic, has reversed my losses to that of a man 10 to 15 years younger. And I’ve lost some weight. Before using it, I felt old. After using it, I feel alive. . . . My wife, a nurse, was more than skeptical, she thought I’d poison myself with that ugly looking concoction. But when she saw my results, she tried it. Within a month, her joint pain completely disappeared, allowing her to get up off her knees without help or pain. And her hair has returned to the luster and thickness it had when she was in her 30′s.
I gained a few pounds when I moved from Berkeley to Beijing in August. Until I read this, it hadn’t occurred to me that it might be due to kombucha deprivation. (It took three weeks to brew kombucha in Beijing. I have not seen it for sale in Beijing even in Western-style health food stores!) To me, the most interesting change he describes is better hair texture. Perhaps it reflects better digestion. I can’t see why better immune function would improve your hair.
Thanks to Steve Hansen.
From the movie Gladiator:
Slave Trader 1 These slaves are rotten.
Slave Trader 2 It all adds to the flavor.
A big reason I believe we need to eat fermented foods to be healthy is that they taste so good.
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