Liberal Japan

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. Chron’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.