Salivary iodide status as a measure of whole body iodine homeostasis?

Alsaeedi, Eatedal Eenizan ; Rose, Peter; Welham, Simon J.M.

Abstract

Iodine is a trace element required to produce the thyroid hormones, which are critical for development, growth and metabolism. To ensure appropriate population iodine nutrition, convenient and accurate methods of monitoring are necessary. Current methods for determining iodine status either involve a significant participant burden or are subject to considerable intra-individual variation. The continuous secretion of iodide in saliva potentially permits its use as a convenient, non-invasive assessment of status in populations. To assess its likely effectiveness, we reviewed studies analysing the association between salivary iodide concentration (SIC) and dietary iodine intake, urinary iodide concentration (UIC) and/or 24-h urinary iodide excretion (UIE). Eight studies conducted in different countries met the inclusion criteria, including data for 921 subjects: 702 healthy participants and 219 with health conditions. SIC correlated positively with UIC and/or UIE in four studies, with the strength of relationship ranging from r = 0·19 to r = 0·90 depending on sampling protocol, age, and if salivary values were corrected for protein concentration. Additionally, SIC positively correlated with dietary intake, being strongest when saliva was collected after dinner. SIC varied with external factors, including thyroid function, use of some medications, smoking and overall health status. Evidence provided here supports the use of SIC as a viable, low-burden method for determining iodine status in populations. However, small sample sizes and high variability indicates the need for more extensive analyses across age groups, ethnicities, disease states and dietary groups to clarify the relative accuracy and reliability in each case and standardise procedure.

Citation

Alsaeedi, E. E., Rose, P., & Welham, S. J. (2024). Salivary iodide status as a measure of whole body iodine homeostasis?. British Journal of Nutrition, 131(10), 1740-1753. https://doi.org/10.1017/S000711452400031X

• Journal Article Type: Article
• Acceptance Date: Jan 23, 2024
• Online Publication Date: Jan 30, 2024
• Publication Date: May 28, 2024
• Deposit Date: Jan 29, 2025
• Publicly Available Date: Jan 29, 2025
• Journal: British Journal of Nutrition
• Print ISSN: 0007-1145
• Electronic ISSN: 1475-2662
• Publisher: Cambridge University Press
• Peer Reviewed: Peer Reviewed
• Volume: 131
• Issue: 10
• Pages: 1740-1753
• DOI: https://doi.org/10.1017/S000711452400031X
• Public URL: https://nottingham-repository.worktribe.com/output/30665342
• Publisher URL: https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/salivary-iodide-status-as-a-measure-of-whole-body-iodine-homoeostasis/7130AA34A25EBEF6239FDE309571F047
• Additional Information: Copyright: © The Author(s), 2024. Published by Cambridge University Press on behalf of The Nutrition Society; License: This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.; Free to read: This content has been made available to all.