Vitamin A deficiency is the leading cause of childhood blindness and a preventable underlying cause for many childhood deaths in low- and middle-income countries (LMICs). Thanks to multiple strategies – supplementation, food fortification and, above all, better diets – substantial progress has been made in the last decades, and vitamin A deficiency is decreasing in several regions. Despite this progress, vitamin A deficiency remains a public health concern in sub-Saharan Africa and South Asia. With increasing access to better diets, the decision to scale back or redesign supplementation programmes has become relevant. Too high intake of vitamin A may cause liver damage and disturb bone mineralisation, so while it is essential to prevent deficiency, overconsumption should also be avoided.
Accurate data on vitamin A status is key to decide when to stop vitamin A supplementation and to which population groups. Conventional methods only measure vitamin A deficiency, but a stable isotope technique can accurately measure vitamin A status, from deficiency to excess. The method is already used for research purposes, and its ability to measure vitamin A status under different circumstances when vitamin A intakes are high was confirmed in a Coordinated Research Project (CRP). The method requires fine tuning to meet its full potential to support decision making in nutrition programmes.
Building on the findings from the recently finalised CRP, IAEA is launching a new five-year CRP on optimising the retinol isotope dilution (RID) technique for use in population surveys. This CRP will support five teams to research aspects that will enable non-experts to use the method in population surveys. Participating teams must have experience with field aspects of the RID technique and assessment of dietary intake of vitamin A.
Overall objective
The overall objective is to provide new knowledge on how to use the RID technique in larger population surveys to assess vitamin A status, from deficiency to excess.
Specific objectives
- To establish cut-off values of the RID outputs to define vitamin A deficiency and excess
- To explore how the RID technique is affected by inflammation at the time of dosing
- To generate coefficients for accurate calculation of vitamin A status in various population groups
- To examine how the existing methodology can be simplified to suit population surveys without loss of accuracy
How to join this CRP
Please submit the Proposal for Research Contract or Agreement form by email to the IAEA’s Research Contracts Administration Section, no later than 1st September 2021. Note that the same template can be used for both research and technical contract.
For further information related to this CRP, potential applicants should use the contact form on the CRP page.
