Typecast? Check out the least and most common blood types

Blood – everyone’s got it. In fact, an adult who weighs between 150 and 180 pounds has around 1.2 to 1.5 gallons of blood in their body. This makes up approximately 10% of an adult’s weight. ⬤ Blood type is determined by “the presence or absence of certain antigens – substances that can trigger an immune response if they are foreign to the body,” according to American Red Cross. ⬤ There are eight common blood types: A positive, A negative, B positive, B negative, O positive, O negative, AB positive and AB negative. But which is the rarest? Here’s what to know.

What is the rarest blood type?

Based on statistics, the rarest blood type is AB negative. According to the American Red Cross, AB negative blood type occurs in “1% of Caucasian, 0.3% of African American, 0.1% of Asian and 0.2% of Latino American” populations.

There are more than 600 other known antigens, and the absence or presence of them creates “rare blood types.” Someone’s blood type is considered rare if they lack “antigens that 99% of the people are positive for.” If you lack an antigen 99.9% of people have, your blood type is “extremely rare.”

The blood type of B negative also is uncommon, occurring in “2% of Caucasian, 1% of African American, 0.4% of Asian and 1% of Latino American” populations, according to the American Red Cross.

What is the most common blood type?

The most common blood type is O positive, which 37% of the U.S. population

has, the American Red Cross says.

To break down further, O positive occurs in “37% of Caucasian, 47% of African American, 39% of Asian and 53% of Latino American,” populations, according to the American Red Cross. O positive is in high demand since it is “the most frequently occurring blood type.”

The second most common blood type is A positive, which occurs in “33% of Caucasian, 24% of African American, 27% of Asian and 29% of Latino American” populations.

What type is the universal donor?

The universal donor is O negative. People with this blood type are considered universal donors since O negative can be used in emergency situations for transfusions on any blood type.

However, O negative is not an extremely common – only 7% of the U.S. population has O negative blood, the American Red Cross says. This blood type is found in “8% of Caucasian, 4% of African American, 1% of Asian and 4% of Latino American” populations.