![]() |
|
|
Institute of Food Science ETHZ, Laboratory of Human Nutrition, CH-8803 Rüschlikon, Switzerland
2To whom correspondence should be addressed. E-mail: hurrell{at}ilw.agrl.ethz.ch.
Vegetable protein sources are often mixed with cereals for complementary feeding. Both contain high levels of phytic acid, which can inhibit trace element and mineral absorption. In adults, phytic acid has been reported to inhibit the absorption of iron, zinc, calcium and manganese but not copper. There are far fewer studies in infants. Phytic acid is a strong inhibitor of iron absorption in both infants and adults, but its influence on zinc absorption in infants seems to be modest and perhaps most important in children recovering from infection. The influence of phytic acid on calcium and magnesium absorption would seem of minor importance. Because iron and zinc deficiencies are widespread in infants and young children in developing countries, the bioavailability of iron and zinc from complementary food is a major concern. Iron absorption may be as low as 23% from porridge based on whole-grain cereals and legumes (phytic acid
1 g/100 g) even in iron-deficient subjects. Decreasing phytic acid by 90% (
100 mg/100 g dried product) would be expected to increase absorption about twofold and complete degradation perhaps fivefold or more. More modest reductions in phytic acid content may not usefully improve iron absorption. Complete enzymatic degradation of phytic acid is recommended. If this is not possible, it is recommended that the molar ratio of phytic acid to iron in an iron-fortified food be <1, preferably <0.5. At these low levels of phytic acid (2030 mg/100 g dried product), zinc absorption should be satisfactory.
KEY WORDS: complementary food phytic acid iron zinc bioavailability
This article has been cited by other articles:
![]() |
T. D. Thacher, O. Aliu, I. J. Griffin, S. D. Pam, K. O. O'Brien, G. E. Imade, and S. A. Abrams Meals and Dephytinization Affect Calcium and Zinc Absorption in Nigerian Children with Rickets J. Nutr., May 1, 2009; 139(5): 926 - 932. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. H. Paul, K. L. Dickin, N. S. Ali, E. C. Monterrosa, and R. J. Stoltzfus Soy- and Rice-Based Processed Complementary Food Increases Nutrient Intakes in Infants and Is Equally Acceptable with or without Added Milk Powder J. Nutr., October 1, 2008; 138(10): 1963 - 1968. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Mostyn, S. Sebert, J. C Litten, K. S Perkins, J. Laws, M. E Symonds, and L. Clarke Influence of porcine genotype on the abundance of thyroid hormones and leptin in sow milk and its impact on growth, metabolism and expression of key adipose tissue genes in offspring. J. Endocrinol., September 1, 2006; 190(3): 631 - 639. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. K. Lutter and K. G. Dewey Proposed Nutrient Composition for Fortified Complementary Foods J. Nutr., September 1, 2003; 133(9): 3011S - 3020. [Abstract] [Full Text] [PDF] |
||||