ABO blood group system During the 1930s, connecting blood groups to personality types became popular in Japan and other areas of the world. Studies of this association have yet to confirm its existence definitively. Other popular but unsupported ideas include the use of a blood type diet, claims that group A causes severe hangovers, group O is associated with perfect teeth, and those with blood group A2 have the highest IQs. Scientific evidence in support of these concepts is nonexistent. ABO blood group system The ABO blood group system is used to denote the presence of one, both, or neither of the A and
Jehovah's Witnesses and blood transfusions of outdated medical beliefs. Dissident Witnesses say the Society's use of Leviticus 17:12 to support its opposition to blood transfusions conflicts with its own teachings that Christians are not under the Mosaic law. Theologian Anthony Hoekema claims the blood prohibited in Levitical laws was not human, but animal. He cites other authors who support his view that the direction at Acts 15 to abstain from blood was intended not as an everlasting covenant but a means of maintaining a peaceful relationship between Jewish and Gentile Christians. He has described as "absurd literalism" the Witnesses' use of a scriptural prohibition on