10 Reasons Japanese don't have longer intestines
It is commonly thought in Japan, that Japanese have longer intestines than anyone else. Here are ten reasons why I don't think Japanese have longer intestines than everyone else. I'm sure there are more.
1. There is no *single* claim but many, many different claims. There is no consistency between claims regarding length. One claim might be a meter or two, another might say Japanese have double the length of intestines.
2. Nearly all claims are between Japanese and *oubeijin* (Americans/ Europeans). This strikes me as odd. The group of Americans/Europeans is certainly too large to really be lopped together like this.
3. I could never trace the claim to any one study. It was always explained like this. Herbivores have longer intestines, carnivores shorter. Japanese ate lots of rice and fish, and American/Europeans lots of meat. So Japanese have shorter intestines. (There is no discernible source for this claim. It's always taken as common wisdom.)
4. The introduction of lots of meat into the diet is a fairly new phenomena even in Europe, I think. For example, during ancient and medieval times, Europeans mostly subsisted on grains, right? Perhaps even up until modern times.
5. The claim is always made in the context of diet. That is, the claim is made, then it is stated that Japanese should not each too much meat and must eat more rice. (The claim appears in lots of faddish health books in Japan.)
6. The claim is reminiscent of some claims that were circulating in Germany prior to WWII. For example, it was often said that Germans were agriculturalists, while Jews were meat eaters. Various physical and psychological traits were then often derived from this. (For this see _Myth of Japanese Uniqueness_ by Peter Dale)
7. I could find nothing of it in medical journals that I searched. In particular, I paid attention to transit time (the time it take medicine to be ingested) and found that medicine manufactures made no special allowance for the Japanese. Dosages are roughly similar for Japanese if not the same. If there were serious differences in intestinal length, dosages would have to be adjusted, right? Can someone refute this?
8. Karl Van Wolferen in _The Enigma of Japanese Power_, citing an article in the Japan Times as his source, bluntly states the claim is WWII propaganda. The reason was to help people cope with poor food availability during WWII.
9. Crohn's disease (short bowel syndrome) seems to be treated the same in Japan as in the US.
10. If one sticks mostly to standard reference books no special note is made of long Japanese intestines. Reference books in English and Japanese generally stick to the same claim, that the small intestine is about six meters give or take some.
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I just found a funny blog
I just found a funny blog entry on this.
Check it out!
[...] The problem here is
[...] The problem here is with the the word “race” being fairly nebulous. I mean what constitutes race? It’s a pseudo-scientific concept to begin with. Japanese regard themselves as having special long intestines and special brains as well. Often reasons such as upbringing and diet are invoked in cases like this. That is because Japanese have a special diet of rice and fish, they have special long intestines. Speaking the Japanese language from birth actually produces physical changes on the brain (so it’s claimed). I’m sure there’s a sense in which, by being away from Japan for so long, nikkeijin have been physically transformed into gaijin. However, it must be pointed out that nikkeijin are only second tier gaijin, but not “pure” gaijin. [...]
Food Shortage Propaganda
Van Wolferen's claim seems to be accurate, in that I read it in somewhat more detail in another old book, I believe by the prolific Jack Seward, two or three decades ago. In his version, as I remember it, he attributes it to a specific Japanese government official. Japanese in the early part of the 20th century were adopting some Western ways, but during the economic crises caused by Japan's militarization it wasn't possible to meet market demand for meat and the like, so the "intestine theory of food digestion" was cooked up. What I never understood was how *longer* intestines would have made meat digestion harder. Wouldn't it have been the opposite?
I Googled and found this page after a recent bout of colitis took me to my Japanese doctor, who told me that my intestine was shorter than Japanese, therefore stronger, therefore I had been able to put up with bad American style food longer without having any problem. A "week" Japanese would have gotten colitis sooner. This was not one of those old geezer physicians, but a relatively young Japanese doctor. Jeez! This story is really firmly established in Japan.
We all evolved as
We all evolved as hunter-gatherers over millions of years. Agriculture didn't appear until 10-12,000 years ago, a small bump on the road of evolution. For many millions of years, our ancestors ate what meat they could hunt, and what fruits, vegetables, and herbs they could gather. Grains and foods produced from them were not eaten until very recently in the evolutionary lifespan of our species. None of the various human populations in the world are especially suited to eating a large percentage of their diet in grain form. A lot of recent dietary studies have borne out the fact that people are healthier on some type of paleo eating plan, with a larger part of the diet coming from proteins and fats, and carbs taking the fresh fruit and vegetable form, drastically reducing grains.
Oh, I forgot to mention
Oh, I forgot to mention that:
The truth is, Japan was one of the last Eurasian countries to develop an agrarian society. According to Wikipedia, agriculture reached Greece from the Middle-east by 7,000 BC, and it had reached northwestern Europe by ca. 5,000 BC. The Jomon people (until c. 300BC) of Japan were primarily hunters. Farming came to Japan with the Yayoi invaders from Korea from the 3rd century BC, but did not spread to most of Japan (but Hokkaido) until the 1st century AD, at the height of the Roman Empire - and several centuries after the golden age of Ancient Greece.
If agriculture came late to Japan, how is it that the Japanese evolved longer intestines will other peoples didn't? That is, assuming that evolution could act that fast (it typically does not). You won't find many Japanese that know their own history well enough to discuss this, let alone world history.
crohn's disease
crohn's disease
I googled this for the same
I googled this for the same reason everybody does: they've been told by Japanese people that their intestines are longer. I found Todd's comments to be particularly incisive and conclusive.
Apparently there used to be a wikipedia article about this but it was deleted.