Total Body Vitamin A Before and After Vitamin A Supplementation in a Community Where Liver is Frequently Eaten

Study Overview
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Brief Summary
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This study will assess total body vitamin A pool size, as well as liver vitamin A stores, by means of stable isotope dilution in preschool children from a South African community where liver, an exceptionally rich source of vitamin A, is frequently eaten, and the children exposed to vitamin A fortified staple foods, as well as a vitamin A supplementation programme.

Detailed Description
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Serum retinol, the most commonly used indicator to assess vitamin A status, is homeostatically controlled and, although it is able to detect deficiency, it does not necessarily reflect liver stores or measure excessive vitamin A intake. The stable isotope dilution method is able to measure total vitamin A body pool size over the vitamin A status continuum, including the sub-toxic range,and would add valuable information about the vitamin A status in a community where liver (an exceptionally rich source of vitamin A) is frequently eaten, and children also exposed to other vitamin A interventions. Total body vitamin A will be assessed before and 4 weeks after a high dose vitamin A supplement given to the children as part of the national vitamin A supplementation program. The confounding effect of infection/inflammation on the biomarkers of vitamin A status will also be examined, as well as how serum retinol and retinol binding protein relate to each other, and to vitamin A pool size.

Official Title
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Total Body Vitamin A Pool Size in Preschool Children Before and After Vitamin A Supplementation in an Impoverished South African Community Where Liver is Frequently Eaten and Children Exposed to Vitamin A Fortified Staple Foods

Conditions
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Hypervitaminosis A

Intervention / Treatment
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* Dietary Supplement: Vitamin A supplement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Living in the study area; Must not have received a vitamin A supplement in the preceding month Exclusion Criteria: Severe anaemia (haemoglobin < 9 g/dL); Fever (body temperature > 38°C)

Ages Eligible for Study
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Minimum Age: 36 Months
Maximum Age: 60 Months

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Dietary Supplement: Vitamin A supplement|200 000 IU vitamin A (once-off dose), given to participants as part of the national vitamin A supplementation program|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of participants with total body vitamin A stores in the sub-toxic range as measured by stable isotope dilution using 13C-retinol as tracer |  | 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of participants with elevated inflammation markers, as measured by elevated C-reactive protein (CRP) and alpha-1-acid glycoprotein (AGP), and their confounding effect on serum retinol, retinol binding protein, and body vitamin A stores |  | 4 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vitamin A stores, Stable isotope dilution, Multiple vitamin A interventions