Elimination, and Transport of Copper

The average North American diet contains 3-5 mg copper per day. Because of the ubiquitous presence of copper in food constituents and even in drinking water, it is difficult to devise a balanced diet composed of natural foods that contains less than 1 mg copper per day. The daily minimal requirement of copper for the adult man is stated to be 2 mg per day (C5). Infants require 0.05 mg/kg body weight per day (Nl). These figures are only approximate and most probably far too high, since copper deficiency has not been produced with much lower intakes of copper (W3). 

Naturally occurring copper deficiency has not been proven to occur in man, most probably because of minimal requirements and plentiful supply in the diet. The copper deficiency, suspected on the basis of low serum copper levels in infants with various types of protein-losing enteropathy (S48, Z3), is of doubtful pathognomonic significance. 

Copper deficiency occurs naturally and can be produced experimentally in a number of animal species. The chapter on copper in Underwood s Trace Elements in Human and Animal Nutrition is an excellent source of information pertaining to this subject (U2). 

Radioactive copper given by mouth to human subjects appears very rapibly in the blood (B9, C5, Jl), which indicates rapid absorption, probably from the upper parts of the small intestine and stomach. 

While absorption of the copper contained in foods of plant origin is seemingly efficient, it has been reported that rats fed on raw meat developed copper deficiency. This suggests that the copper present in raw meat is not avaliable for absorption. Experience in this direction is well summarized and the pertinent literature quoted in a recent article by Moore et al. (M29). Guggenheim (G16), on the other hand, presents recent evidence to the effect that the meat anemia in mice is due to the high zinc content of meat in the presence of low but, by itself, adequate amounts of copper, and that a concomitant lack of calcium further aggravates the situation. One must wait to see whether this applies to the raw meat copper deficiency of 

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