Tags

Type your tag names separated by a space and hit enter

Total Iron Bioavailability from the US Diet Is Lower Than the Current Estimate.
J Nutr. 2015 Nov; 145(11):2617-21.JN

Abstract

BACKGROUND

Total (heme and nonheme) iron bioavailability from the US diet has been estimated to be 18% based on a single human absorption study. New data, however, suggest that it may be time to revisit this estimate.

OBJECTIVE

We estimated total iron bioavailability from the US diet with the use of our recently reported algorithm that estimates nonheme iron absorption and a conservative value for heme iron absorption.

METHODS

We used dietary intake and biomarker information from the NHANES 2001-2002, MyPyramid Equivalents Database, and Food and Nutrient Database for Dietary Studies. The survey package in R software was used to estimate means and CIs, taking into account the strata, primary sampling units, and appropriate survey weight. We implemented 2 different approaches to estimate total iron absorption. In the first approach, we included all survey participants but adjusted the geometric mean of nonheme iron absorption to 15 μg ferritin/L serum to mimic values of individuals with no iron stores; in the second approach, absorption was estimated for only nonanemic subjects with no iron stores. A total sample size of 6631 was used based on availability of dietary and iron status biomarker data and C-reactive protein concentration ≤ 6 mg/L.

RESULTS

The geometric mean (95% CI) of unadjusted nonheme iron absorption for all subjects was 3.7% (3.6%, 3.8%), higher in female subjects [5.6% (5.4%, 5.7%)] than male subjects [2.6% (2.5%, 2.7%)] (P < 0.0001). Nonheme iron absorption was lower in non-Hispanic whites [3.5% (3.4%, 3.6%)] than Mexican Americans [4.5% (4.2%, 4.8%)] and non-Hispanic blacks [4.4% (4.1%, 4.7%)]. Estimated total iron absorption was 15.5% or 15.1%, depending on which approach was used to carry out the calculations.

CONCLUSION

This study provides useful data for evaluating the current value of iron bioavailability from the US diet.

Links

Publisher Full Text

Authors+Show Affiliations

Armah SM
Department of Food Science and Human Nutrition and.
Carriquiry AL
Department of Statistics, Iowa State University, Ames, IA.
Reddy MB
Department of Food Science and Human Nutrition and mbreddy@iastate.edu.

MeSH

AdolescentAdultAscorbic AcidBiological AvailabilityC-Reactive ProteinCalcium, DietaryChildChild, PreschoolDietEnergy IntakeFemaleFerritinsHumansIntestinal AbsorptionIron, DietaryMaleMiddle AgedNutrition SurveysPhytic AcidPolyphenolsRecommended Dietary AllowancesTeaUnited StatesYoung Adult

Pub Type(s)

Journal Article

Language

eng

PubMed ID

26377760

Citation

Armah, Seth M., et al. "Total Iron Bioavailability From the US Diet Is Lower Than the Current Estimate." The Journal of Nutrition, vol. 145, no. 11, 2015, pp. 2617-21.
Armah SM, Carriquiry AL, Reddy MB. Total Iron Bioavailability from the US Diet Is Lower Than the Current Estimate. J Nutr. 2015;145(11):2617-21.
Armah, S. M., Carriquiry, A. L., & Reddy, M. B. (2015). Total Iron Bioavailability from the US Diet Is Lower Than the Current Estimate. The Journal of Nutrition, 145(11), 2617-21. https://doi.org/10.3945/jn.115.210484
Armah SM, Carriquiry AL, Reddy MB. Total Iron Bioavailability From the US Diet Is Lower Than the Current Estimate. J Nutr. 2015;145(11):2617-21. PubMed PMID: 26377760.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Total Iron Bioavailability from the US Diet Is Lower Than the Current Estimate. AU - Armah,Seth M, AU - Carriquiry,Alicia L, AU - Reddy,Manju B, Y1 - 2015/09/16/ PY - 2015/01/14/received PY - 2015/08/14/accepted PY - 2015/9/18/entrez PY - 2015/9/18/pubmed PY - 2016/2/13/medline KW - US diet KW - bioavailability KW - ethnicity KW - gender KW - nonheme iron SP - 2617 EP - 21 JF - The Journal of nutrition JO - J Nutr VL - 145 IS - 11 N2 - BACKGROUND: Total (heme and nonheme) iron bioavailability from the US diet has been estimated to be 18% based on a single human absorption study. New data, however, suggest that it may be time to revisit this estimate. OBJECTIVE: We estimated total iron bioavailability from the US diet with the use of our recently reported algorithm that estimates nonheme iron absorption and a conservative value for heme iron absorption. METHODS: We used dietary intake and biomarker information from the NHANES 2001-2002, MyPyramid Equivalents Database, and Food and Nutrient Database for Dietary Studies. The survey package in R software was used to estimate means and CIs, taking into account the strata, primary sampling units, and appropriate survey weight. We implemented 2 different approaches to estimate total iron absorption. In the first approach, we included all survey participants but adjusted the geometric mean of nonheme iron absorption to 15 μg ferritin/L serum to mimic values of individuals with no iron stores; in the second approach, absorption was estimated for only nonanemic subjects with no iron stores. A total sample size of 6631 was used based on availability of dietary and iron status biomarker data and C-reactive protein concentration ≤ 6 mg/L. RESULTS: The geometric mean (95% CI) of unadjusted nonheme iron absorption for all subjects was 3.7% (3.6%, 3.8%), higher in female subjects [5.6% (5.4%, 5.7%)] than male subjects [2.6% (2.5%, 2.7%)] (P < 0.0001). Nonheme iron absorption was lower in non-Hispanic whites [3.5% (3.4%, 3.6%)] than Mexican Americans [4.5% (4.2%, 4.8%)] and non-Hispanic blacks [4.4% (4.1%, 4.7%)]. Estimated total iron absorption was 15.5% or 15.1%, depending on which approach was used to carry out the calculations. CONCLUSION: This study provides useful data for evaluating the current value of iron bioavailability from the US diet. SN - 1541-6100 UR - https://www.unboundmedicine.com/medline/citation/26377760/Total_Iron_Bioavailability_from_the_US_Diet_Is_Lower_Than_the_Current_Estimate_ L2 - https://academic.oup.com/jn/article-lookup/doi/10.3945/jn.115.210484 DB - PRIME DP - Unbound Medicine ER -