Regular Consumption of High Phytate Reduces Inhibitory Effect of Phytate on Iron Absorption

Not Applicable

Completed

• Conditions: Iron Bioavailability
• Interventions: Other: High phytate intake; Other: Low phytate intake

• Registration Number: NCT02370940
• Lead Sponsor: Iowa State University

Brief Summary

The purpose of this study is to investigate whether regular consumption of phytate dampens its negative effect on nonheme iron absorption.

Detailed Description

Phytate is one of the main inhibitors of nonheme iron absorption. High phytate consumption is of concern in developing countries because of the high prevalence of iron and zinc deficiency in these countries. In this study, we investigated the effect of habitual consumption of a high phytate diet on the inhibitory effect of phytate on nonheme iron absorption. Thirty-two non-anemic female subjects with ferritin ≤ 30µg/L were randomized into two groups, after matching for ferritin concentration. Each group consumed either high or low phytate foods that were provided for 8 wk. Iron bioavailability from a high phytate test meal was measured using area under the curve (AUC) for serum iron at baseline and after the intervention.

Study Timeline

• Study Start: 2013-01
• Primary Completion: 2013-04
• Study Completion: 2013-04
• Status Verified: 2015-02
• Study First Submitted: 2015-02-11
• Study First Submitted QC: 2015-02-19
• Last Update Submitted: 2015-02-19
• Study First Posted: 2015-02-25
• Last Update Posted: 2015-02-25

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 32

Inclusion Criteria

• Marginal iron status (Serum ferritin <30ug/L)
• BMI in the range 18.5-24.9kg/m2
• Willing to modify diet to increase or decrease phytate intake
• Willing to give multiple blood samples at beginning and end of study

Exclusion Criteria

• Pregnant
• Lactating
• Smoker
• Anemic (hemoglobin <120 g/L)
• Has gastro-intestinal disease/condition that can affect absorption

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
High Phytate Diet	High phytate intake	The high phytate diet group was required to consume a high phytate diet for 8 weeks. The high phytate foods were provided for subjects. They received whole grain ready-to-eat cereals, whole wheat pasta/spaghetti, tortillas, bagels, bread and dinner rolls, corn tortillas, brown rice, canned black beans, edamame and tofu, and were encouraged to consume generous amounts of nuts and other legume products high in phytate.
Low Phytate Diet	Low phytate intake	The low phytate diet group was required to consume a low phytate diet for 8 weeks. They received foods similar to those for the high phytate diet group but which were made from refined wheat and white rice, eggs and cheese, and were instructed to avoid high phytate foods.

Primary Outcome Measures

Name	Time	Method
Area under the curve for serum iron for assessing bioavailability	8 weeks