Micronutrient Bioavailability From Wheat

Not Applicable

• Conditions: Healthy

• Registration Number: NCT05536947
• Lead Sponsor: King's College London

Brief Summary

The purpose of this study is to determine if physical disruption of wheat aleurone cell walls (micro-milling) increases micronutrient availability.

Detailed Description

This research project is a short-term dietary intervention study to investigate the bio-availability of iron and zinc from wheat. Approximately 50% of iron and 30% of zinc in the United Kingdom diet is provided by cereals and cereal products (e.g. bread and breakfast cereals). The localisation of both iron and zinc metals in wheat is largely confined to the aleurone layer, a single layer of cells located between the centre (endosperm) and outer layers (testa and pericarp). The aleurone layer is removed during the production of white flour. For this reason, since 1953 it has been mandatory to add iron to flours at the mill to restore iron to levels present in wholegrain flour (The Bread and Flour Regulations, 1998).

The investigators have shown that aleurone cells are resistant to physical disruption and digestion as they pass along the gastrointestinal tract and are excreted intact in faeces. The investigators believe that disruption of wheat aleurone cell walls prior to food manufacturing would therefore increase iron and zinc availability. Using wholegrain flour and purified wheat aleurone flour the investigators have shown that micro-milling, a process which reduces particle size of flour from approximately 100μm to 10μm, ruptures the aleurone cell walls, and increases iron availability, i.e. the amount absorbed by intestinal cells, compared with flour produced using standard milling techniques (which does not break down the aleurone layer).

Based on these initial findings, the current study therefore has 2 main aims:

(i) to determine whether physical disruption of the aleurone (by micro-milling) in wholegrain flour increases iron and zinc availability from wholegrain bread.

(ii) to determine whether addition of micro-milled aleurone flour to white flour increases iron availability from white bread.

Study Timeline

• Status Verified: 2021-11
• Study Start: 2021-11-26
• Study First Submitted: 2021-12-14
• Study First Submitted QC: 2022-09-07
• Last Update Submitted: 2022-09-07
• Study First Posted: 2022-09-13
• Last Update Posted: 2022-09-13
• Primary Completion: 2022-12
• Study Completion: 2022-12

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: Female
• Target Recruitment: 25

Inclusion Criteria

• Healthy pre-menopausal women
• Serum ferritin below 30 μg/L
• Plasma zinc below 13.8 μmol/L.

Exclusion Criteria

• Allergic to gluten or wheat
• Pregnant
• Post-menopausal women
• History of alcohol or substance abuse
• History of Cardiovascular Disease, diabetes, cancer, kidney, liver or intestinal disease, gastrointestinal disorder or use of drugs likely to alter gastrointestinal function.
• Donated blood recently (within 3 months prior to screening visit)
• Volunteers planning to take any mineral or vitamin supplements during the course of the study.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Primary Outcome Measures

Name	Time	Method
Analysis of 57-Fe incorporation into erythrocytes	Through study completion, an average of 1 year	Determines Fe incorporation from test meal into Red Blood Cells
Urinary excretion of Zinc	Through study completion, an average of 1 year	Determine excretion of Zinc in urine samples to assess Zinc bioavailability

Secondary Outcome Measures

Name	Time	Method
Analysis of iron status biomarkers from blood samples	Through study completion, an average of 1 year	Determine Hepcidin concentration from sample

Trial Locations

Locations (1)

King's College London; 🇬🇧 London, United Kingdom