Blood can be grouped using various systems. Two of the most well known systems are the Rh system and the ABO system. The ABO blood types were found in the beginning of the 20th century by Karl Landsteiner. He learnt that blood transfusions could sometimes result in the death of the recipient and then discovered the cause. He discovered that certain blood types had antigens and antibodies. For example: A type contains antigen A and antibody anti-B, B type has antigen B and antibody anti-A, AB type has both antigens A and B but no antibody, whereas O blood type contains no antigen but has both antibodies anti-A and anti-B. Antigens coat the surface of red blood cells and quite susceptible to rejection from the antibody. If a donor antigen was rejected by the recipient antibody, it would cause agglutination or destruction of the donor red blood cells in the body of the recipient.
A few O blood type facts are that O does not have ABO antigens therefore will not be rejected by other blood types and that it has all ABO antibodies therefore will always reject blood types aside from O. That is why people with type O blood are called “universal donors”. More fun facts of the O blood type are that mosquitoes in general prefer the O type to others (higher risk of contracting malaria) and that type O individuals are more susceptible to cholera and peptic ulcers. By natural selection, O blood type is probably the most common throughout the whole world.
The less scientific facts of the O blood type concern with personalities of type O individuals. Some consider type O people as energetic and social, as well as flexible in the terms of their viewpoint. Others think that type O people are quitters and often give up midway. Although most people agree that they are honest and respectful toward others and have very strong confidence.
As the most well known blood group classification system, the ABO system gives rise to a kind of fad diet called “The Blood Group Diet”. The base of this diet is the existence of antigens that form different blood types. These antigens allegedly react either positively or negatively toward certain kind of food. Based on this diet, type O people are basically carnivores, A are vegetarians, B are omnivores and AB are mixed diet eaters. For type O individuals, practicing this diet might have some pros and cons. The pros: they can eat meat and fish freely as the diet calls for high protein intake, vegetable haters don’t have to eat vegetable too much. The cons: facts stated that type O individuals are already susceptible to various diseases, so practicing this diet will only add a notch in the disease column because it increases the risk of developing heart disease.
