Effect of protein level and protein source on zinc absorption in humans.
The effect of increasing levels of various protein sources on zinc absorption from a legume-based meal was studied in humans with the use of a radionuclide technique. The meals were extrinsically labelled with 65Zn and absorption was determined from measurements of the whole-body retention of the isotope. The mean fractional zinc absorption for the 13 meals was 24.7 +/- 6.9% and was only influenced by the protein content of the meal to a limited extent (r = 0.45). However, the amount of zinc absorbed from the meals was strongly correlated with both the protein (r = 0.85) and zinc content (r = 0.86): 5.9 +/- 1.7 mumol of zinc was absorbed from the basal bean meal which had the lowest protein content; the addition of low zinc chicken doubled the protein content and increased zinc absorption to 10.3 +/- 2.0 mumol; the addition of zinc-rich beef also doubled the protein content, however, zinc absorption was increased to 15.9 +/- 4.7 mumol. It is concluded that the zinc content of the main protein source of the diet determines the amount of zinc absorbed to a large extent. However, relatively small amounts of animal protein can significantly improve the value of a legume-based meal as a source of zinc.
Sandström
B
B
Department of Clinical Nutrition, University of Gothenburg, Sweden.
Almgren
A
A
Kivistö
B
B
Cederblad
A
A
D000328:Adult; D004044:Dietary Proteins / Q000378:metabolism / Q000494:pharmacology*; D007887:Fabaceae; D005260:Female; D006801:Humans; D007408:Intestinal Absorption; D008297:Male; D008460:Meat; D010833:Phytic Acid / Q000032:analysis; D014674:Plant Proteins, Dietary / Q000494:pharmacology; D010946:Plants, Medicinal; D014915:Whole-Body Counting; D015032:Zinc / Q000008:administration & dosage / Q000493:pharmacokinetics*
D004044:Dietary Proteins; D014674:Plant Proteins, Dietary; D010833:Phytic Acid; D015032:Zinc