Is there a best blood type? The ups and downs of A, B, AB and O...

According to the American Heart Association (AHA), A, B, and AB blood types are associated with a greater risk of dangerous ...
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Understanding different blood types: A, B, AB, and O

Medically reviewed by Amelia MacIntyre, DO There are different blood types: A, B, AB, and O, with each also being Rh-positive or Rh-negative.Knowing your blood type is important for safe blood ...