I have a rare blood type—AB+, which only 4 percent of the U.S. has—and secretly, I always thought it made me kind of special, even though I had no basis for that belief. But in Japan, blood type is used to determine one’s personality and temperament. Like astrology, the scientific community often dismisses blood type as an indicator of personality, but that doesn’t stop its popularity in Japanese women’s magazines, where blood type horoscopes are published. In Japanese video games, blood type is commonly a dimension in character creation. In fact, some Japanese might even be shocked if a foreigner didn’t know her blood type.
The history of the theory that blood type determines personality is actually a dark one. In 1900, Austrian scientist Karl Landsteiner discovered the four blood types. Like 19th-century scientists who used brain size (the larger the brain, the more advanced) to propagate theories of racial and gender superiority, many (white) scientists used the blood type theory as a way to push forward their own ideas of racial supremacy. Scientists from the west suggested (falsely, obviously) that Asians were inferior and sub-human since the vast majority of them—like animals—had type B blood. In 1927, Takeji Furukawa, a Japanese professor, introduced the theory to the Japanese public in a paper entitled, “The Study of Temperament Through Blood Type.” Even though he lacked the proper credentials and backed up nothing scientifically, the public embraced the idea of blood type as a determination of personality. The Japanese government even commissioned a study to determine if they could breed better soldiers. In the 1970s, a book by Masahiko Nomi revived the idea, which is still popular with the general Japanese public. In 2008, four books on the topic have hit Japan’s top ten bestseller lists.
Find Out Your Blood Type
One of the easiest ways to find out your blood type is to give blood. Since it has to be matched for donation, they type it anyway, so you can always ask. If you’re pregnant, doctors administer certain blood tests to assess potential genetic problems, so determining the mother’s blood type is standard. You can ask your doctor to perform a test when you get blood drawn, but since it isn’t usually medically relevant, you may have to pay for the test. The easiest way? Ask your parents; they probably know.
