Why Are the Japanese Obsessed with Blood Type?

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There are numerous aspects of every culture that many of us would consider fascinating, but few are more intriguing than Japan’s obsession with blood type.

This element of biological variation or your ‘ketsuekigata’ (血液型) means a lot more than simply the compatibility for organ donation in the Land of the Rising Sun.

Why Are the Japanese Obsessed with Blood Type?
Japanese blood type obsession

Here, we will explore this blood type monomania and how the Japanese believe that compatibility can be found in terms of personality, relationships and more.

When did Japan’s obsession with blood groups begin?

Not as ancient as the Mesopotamian zodiac, this preoccupation was established in the early years of the twentieth century.

It began as a theory posited by Japanese psychologist and Professor at Tokyo Women’s School, Takeji Furukawa and has persisted to this day.

Obsession with blood groups in Japan
Obsession with blood groups

Publishing his thesis as a paper in 1927: The Study of Temperament Through Blood Type, led the way for this to become an established idea.

Although, it is worth noting that his data sample was small and consisted of eleven members of his own family. Nevertheless, it gained popularity a little later that century.

There are claims that this was also military practice around the same time as the paper was published, used to assess soldiers’ abilities, and root out their shortcomings.  

When did the theory become popular?

The notion that blood type equates to personality was revived and arguably solidified in the 1970s by journalist and sumo essayist, Masahiko Nomi.

Writing a series of works in the field of ‘Blood Type Humanics’, he published a number of popular texts on the subject.

The torch was then carried on by his son following his death in the 1980s, just a decade after his initial publication became a best seller: Understanding Affinity by Blood Type.

Key Fact – Blood Type Humanics was a branch of scientific inquiry in Germany in the 1930s.

What does blood type say about a person’s character?

Which traits are ascribed to the A blood type?
Personality and blood type

With an array of visual aids in the form of varying types of graphics available online, there are multiple charts which are designed to guide you in determining the best romantic match or next compatible job.

From A to O, there are specifically defining characteristics attributed to each blood type.

  • If you’re an A, then you’ll be more compatible with an O.
  • Should you fall into the AB category, you’d be better sticking with those of your like.
  • B’s are more compatible with A’s and O’s.

Whatever your compatibility, each type has its own list of both positive and negative traits which differs slightly from source to source. Let’s see what your blood type might say about you!

Which traits are ascribed to the A blood type?

If your blood type is A, then you are considered to be a meticulous and organised individual who pays strict attention to detail, while being both amicable and approachable.

An A-personality is one which is apparently emotionally sensitive. Sometimes preferring to spend time alone, it takes them time to settle into groups.

What can we expect from a B-type personality?

Outgoing, open, and honest, these are but a few believed traits attributed to those with the B blood type.

B-type blood type personality
B-type personality

Opinionated and optimistic, these individuals are often understood to be a little self-involved, but they are also supposedly driven, motivated, and ambitious people who often adopt a one track-mindedness towards their own achievements.

What type of personality is linked with blood type AB?

A rare blood type makes for an even rarer set of personality traits.

The eccentric of the group, AB types are presumably those of us who walk a tightrope between fantasy and reality, juggling various tasks and activities in the pursuit of dreams.

A mixed-up concoction of two blood types, AB-type personalities can purportedly require some patience.

‘O’ What a blood type can say about you?

Considered to be visionaries, people with O-type blood are reportedly the problem solvers of us. Calm in the face of calamity, O-types are leaders and conduct themselves and their affairs constructively.

Having a positive effect on those around them, they are linked with being the more sociable and entertaining of the blood types.

And though their confidence is mistaken for arrogance, their fear of rejection assumes a balance.

Interesting Note – According to some sources, many Japanese Prime Ministers have been in the O blood group.

How commonplace is it in Japan?

Not only appearing as a question on a medical form; it is as normalised as providing your name when you meet someone in Japan.

Asking someone’s blood type is also something you might find on everything from a job application to a Japanese dating profile.

It is very common. In fact, people recommend that if you plan to spend any lengthy time there, you should get to know your own blood type and the traits believed to be associated with it, as well as those of others.

It helps to determine people’s career choices in Japan, it guides them in their love lives, and generally throughout their life journeys.  

Is blood type used to discriminate in Japan?

What does blood type say about a person’s character?
Facts about discrimination

Wherever you may find difference in this world, you are sure to find discrimination.

Sure enough, even at the roots, the theory has precarious links with German scientists in World War 2, and its use in the justification for the protection of German blood by one Adolf Hitler.

B-type blood (purportedly dominant in Asia) was viewed negatively.

Today, prejudice and discrimination rear their heads as “blood-type harassment” which is, although unique to Japan, a real and significant matter in Japanese society. The irony, I’m sure, is not lost.

Final Thoughts

Interwoven within Japanese culture, blood type is something that is part of the fabric. In video games, anime, movies, music, and pretty much all aspects of popular culture in Japan, you will find reference after reference to it and its importance.

And, although many have contested and apparently debunked this theory, it remains prominent to this day.

To answer the original question: why are the Japanese obsessed with blood type? The answer could be extremely complicated but there is one thing we can surely infer: many Japanese people find belief in the theory itself.

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