Add Yahoo as a preferred source to see more of our stories on Google. A person's blood type is determined by "the presence or absence of certain antigens – substances that can trigger an immune ...

Most people don’t spare a thought for their blood type unless they’re in need of a transfusion — but could yours hold secrets to your health? And is one better than the others? There are four main ...

O- blood is the universal donor type because it can be used for anyone. AB+ blood can receive any type of blood, making it the universal recipient. Blood types need to match, or the immune system will ...