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Blood Type Illustration
“What’s your blood type?”
When asked by a stranger in America, this is a weird—and depending on the context, slightly frightening—question. But for some countries, it’s just like asking for your zodiac sign.
In the distant year of 2019, I was in the midst of finishing up my time as an assistant language teacher in Japan, a country where 99% of people know their blood type. In comparison, just over half of Americans know theirs. According to Japanese Blood Type Personality Theory, the types of cells floating in your veins can tell you about what traits you have, how you work in a professional setting, and your best dating prospects.
I found out about this after seeing adorable little starter planters in a Japanese gift shop. Instead of being labeled with the type of flowers you’d grow, it was labeled with blood type. I wanted to pick one up, but wasn’t sure what my blood type was, and even had to send a LINE message to my mom to find out.
Unfortunately, I killed my plant before I found out what B type flowers are. But, B types are said to be irresponsible, so I’m telling myself this was a case of amazing marketing over bad gardening.
With recent reports of blood type having an effect on the severity of COVID-19 effects, more and more people are also likely texting their parents to see if they know their blood type. We spoke with Mark Reding, MD, a hematologist at M Health Fairview, to see how important it is to know our blood type, and about the link between COVID-19 and blood type.
Why do so many Americans not know their blood type? Is it weird I don’t know mine?
“It's really not surprising that many people do not know their blood type,” says Dr. Reding. “This is not something that is tested as part of a routine visit to your doctor. The usual reasons why we would test to determine someone's blood type is if they were in need of a transfusion, or preparing for a major surgery in which a transfusion might be necessary. This is also something that is typically done as part of routine obstetrical care for women.”
What are the benefits of knowing your blood type?
“It's difficult to say there really are any practical benefits of knowing your blood type,” says Dr. Reding. “Even if you knew your blood type in advance, it would always be retested prior to a transfusion, as part of the process to determine compatibility of the blood to be administered. In an emergency situation, where there is not time to figure out a person's blood type, we transfuse type ‘O negative’ blood, as this can be safely given to anyone, regardless of the recipient's blood type.”
What do you think of the link between blood type and COVID-19 severity? Is there any new evidence?
“Since the early days of the COVID-19 pandemic, there has been speculation about whether blood type may play a role in susceptibility to infection or severity of infection,” says Dr. Reding. “Some of the early reports were conflicting, but recently two studies published in October 2020 have suggested pretty convincingly that people with type O blood may have a lower risk of infection with the virus, and a reduced chance of severe complications if they do become infected.”