Bioavailability in infants of iron from infant cereals: effect of dephytinization.
Iron bioavailability from an infant cereal made of wheat flour with a low extraction rate (70%) and cow milk was measured in infants by using a stable-isotope technique. A dephytinized infant cereal was prepared by adding commercial phytase during manufacture, resulting in degradation of 88% of the native phytic acid. Paired comparisons were made to evaluate the effect of phytic acid on iron bioavailability. Both infant cereals contained identical amounts of ascorbic acid and had a molar ratio of ascorbic acid to iron of 2:1. Iron was added as ferrous sulfate. No difference in iron bioavailability was observed in this study; the geometric mean was 8.7% (range: 3.8-16.9%) and 8.5% (range: 3.4-21.4%) from the cereal with native phytic acid (0.08% phytic acid) and the dephytinized cereal (0.01% phytic acid), respectively. Dephytinization of infant cereals containing a relatively low native phytic acid content and high amounts of ascorbic acid is thus unnecessary to ensure adequate bioavailability of iron.
Davidsson
L
L
Nestlé Research Center Lausanne, Switzerland. davidsson@ilw.agrl.ethz.ch
Galan
P
P
Cherouvrier
F
F
Kastenmayer
P
P
Juillerat
M A
MA
Hercberg
S
S
Hurrell
R F
RF
D010832:6-Phytase / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000032:analysis / Q000378:metabolism; D001682:Biological Availability; D002118:Calcium / Q000032:analysis / Q000378:metabolism; D004044:Dietary Proteins / Q000032:analysis / Q000378:metabolism; D002523:Edible Grain / Q000737:chemistry / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D005293:Ferritins / Q000097:blood; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D007223:Infant; D007225:Infant Food / Q000032:analysis*; D019266:Iron, Dietary / Q000032:analysis / Q000493:pharmacokinetics*; D008297:Male; D010833:Phytic Acid / Q000032:analysis / Q000378:metabolism*
D004044:Dietary Proteins; D006454:Hemoglobins; D019266:Iron, Dietary; D010833:Phytic Acid; D005293:Ferritins; D010832:6-Phytase; D001205:Ascorbic Acid; D002118:Calcium