A blood type towel: not as gross as it sounds.

Sometimes, it’s the small cultural differences you notice more than the big ones. For me, one of the most interesting things about Japanese culture is the fascination with blood types. It’s a pretty small aspect of Japanese culture, but it’s so different from what I’m used to in the United States that it really catches my attention. So what does Japan think about different blood types?

In Japan, blood types are linked with personality. Somebody with Type O blood is supposed to have a completely different personality than somebody with Type A blood.

You can think of blood types in Japan much like astrology. Instead of trying to pick up somebody with a cheesy “Hey baby, what’s your sign?,” you might ask your potential mate-to-be “Hey baby, what’s your blood type?”

This blood type craze all started in the 1970s when an author named Masahiko Nomi published a book called Understanding Affinity by Blood Type. The book was an instant best-seller and led to lots more books on the subject.

The Four Different Blood Types

Blood types are a pretty recent discovery. It wasn’t until 1900 that an Austrian scientist discovered the existence of different blood types, a discovery that earned him a Nobel Prize. Since that discovery, scientists have gone on to figure out that different types of blood have different types of antibodies and antigens. I’d be lying if I pretended to have any sort of understanding of what this means in medical or scientific terms, but the most important thing is that immune systems react differently to different kinds of blood types.

There are four different blood types: A, B, O, and AB. I could bore you with the “science” about how each blood type is different, but why do that when I can tell you all the completely unscientific stereotypes for each blood type?

Type A

People with Type A blood are said to be timid, mild-mannered, and pretty earnest. A Type A person might be like that bookworm sitting in the corner of the library. However, Type A people are also known to be stubborn and anxious.

Type B

Type B is particularly important to me, because my blood type is B+! People with Type B are like Miley Cyrus: they can’t be tamed. They’re supposed to be wild, creative free-thinkers. But Type B people are also supposedly erratic and selfish.

Type O

Type O blood is pretty unique. People with Type O blood are known as “universal donors,” because Type O blood can be used in any type of blood transfusion.

If people with Type A blood are Clark Kent, Type O people are Superman. People with Type O blood types are said to be outgoing, confident and passionate with very dominant personalities. It’s said that public figures are often Type O, like politicians and baseball players.

Type AB

Those with Type AB blood are supposed to be somewhere in between Type A and Type B blood. They’re supposed to be social people who are at the same time very calm and in control. But Type AB people can also be very aloof and irresponsible.

Bath salts for people of different blood types, not a bath made of blood.

An astonishing 90% of Japanese know their blood type, which is pretty surprising. It’s my impression that most people in the United States have no idea what their blood type is, unless they have some medical reason for knowing.

How do you find out your blood type? There’s no easy, do-it-yourself way, but you can find out through your medical records or by donating blood. I probably wouldn’t have known my blood type had I not donated blood a few years back and the Red Cross let me know.

Japanese people have used blood types for tons of different things. Compatibility in relationships is sometimes predicted by blood types, and sometimes blood type can be a deal breaker before a potential couple even meets. People will throw parties for people of a certain blood type. Baseball cards will have the player’s blood type listed right along with his batting average.

And of course, as you see in the pictures in this post, there are different products marketed to people with different blood types. Are Type B bath salts really that different from Type A bath salts? Probably not, but that doesn’t stop people from buying them up.

“Hey kids, I’m the father of western medicine! Don’t do drugs!”

Of course, linking blood type to personality is pseudo-science at best. While blood type can tell you certain things about a person (such as what their ancestry might be), no scientist out there will tell you that there’s a tie between personality and blood type.

People justify their fascination with blood type by saying that ancient medicinal figures such as Hippocrates (of the Hippocratic Oath) thought that something in the blood influenced people’s personality. But then again, those Greek dudes had pretty strange (and wrong) ideas about human physiology. If we still listened to the Greeks, we’d be covered in leeches every time we were sick.

There’s also a darker side to blood types in Japanese culture. Some have argued that the Japanese fascination with blood types leads to unfair stereotyping. Blood type has been used for justifying schoolyard bullying (but then again, what hasn’t?). There’s even a term in Japanese for discrimination based on blood type: bura-hara, a combination of the words “blood” and “harassment.”

So what do you guys think? Is there some truth in the stereotypes about blood types? Let me know in the comments!

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