It seems blood types correlate to pH levels,,, this may help us understand why some can eat things other cannot! This is the only study or statement I have seen that brings these two measurements together, so I have no other references to validate this although I find it very interesting!
Celcius

Blood pH Levels: The A-protein is alkaline as it is made up of more of the alkaline amino acids. The B-protein is acidic with more of the acidic amino acids. When the A and B proteins are present together, as in Type AB blood, the pH of the blood is in a balanced state or approximate pH of 7.0. A balanced pH is also indicative of the nutrient minerals being in balance. Individuals with blood types A and O have a propensity to over-excrete the acidic minerals and/or overload alkaline minerals, while those with blood type B have a propensity to overload some acidic minerals and/or over-excrete alkaline minerals, all cases due to copper deficiency.
With type O blood, the alkaline level is so high that even the normal alkaline A-protein cannot be formed, and thus, is missing. According to numerous references and texts dating a few years back and earlier, the pH range for blood in the US was 7.35 – 7.45, with an average pH of 7.40. Assuming Type B is acidic and Type AB is at or near 7.0, this range apparently included type A’s and O’s, which comprised 86% of the US population. The same dated texts and references document the percentages of type O as 45% and type A as 41%, in the US population. It is interesting to note that a clinic in the US recently measured blood pH samples of 259 clients, from January 2004 to June 2005, and found the average pH to be significantly higher, at a high average of 7.54. Assuming Type A’s and O’s were only recorded in the samples, and O’s are the higher pH, this data indicates that type O blood in the US is currently well above 7.60 pH level. Additionally, many individuals with type A blood may change over to type O blood if the pH has increased to a point or range at which the A protein disappears.


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