Geographical and seasonal variation in Iodine content of cow’s milk in the UK and consequences for the consumer´s supply

Coneyworth, Lisa J.; Welham, Simon J.M.; Coulthard, Lauren C.H.A.; Bailey, Elizabeth H.; Young, Scott D.; Stubberfield, Jonathan; Parsons, Louise; Saunders, Neil; Watson, Eamon; Homer, Elizabeth M.

Abstract

Background. Dairy products provide a crucial source of dietary iodine for the majority of the UK population, contributing approximately 30-40 % of daily intake. Fluctuations in the iodine content of purchased milk both seasonally and annually implies potential fragility of iodine supply likely through fluctuating supplementation practices in cow herds. We set out to establish the level of national variation in herds and identify factors which might impact milk iodine content.

Methods. Milk samples were obtained from 98 herds across the UK via the National Milk Laboratories in August and December 2016. Iodine concentration of samples was measured using ICP-MS. Milk samples and feed intake data were additionally taken from 22 cows from the University of Nottingham (UON) dairy herd.

Results. There was considerable variation in milk iodine content from < 0.012 (Limit of Detection) to 1558 µg L-1, with a summer median of 197 µg L-1 and winter median 297 µg L-1. Overall, winter values were higher than summer counterparts (P

Citation

Coneyworth, L. J., Welham, S. J., Coulthard, L. C., Bailey, E. H., Young, S. D., Stubberfield, J., …Homer, E. M. (2020). Geographical and seasonal variation in Iodine content of cow’s milk in the UK and consequences for the consumer´s supply. Journal of Trace Elements in Medicine and Biology, 59, Article 126453. https://doi.org/10.1016/j.jtemb.2020.126453

• Journal Article Type: Article
• Acceptance Date: Jan 9, 2020
• Online Publication Date: Jan 10, 2020
• Publication Date: May 1, 2020
• Deposit Date: Jan 10, 2020
• Publicly Available Date: Jan 11, 2021
• Journal: Journal of Trace Elements in Medicine and Biology
• Print ISSN: 0946-672X
• Electronic ISSN: 1878-3252
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 59
• Article Number: 126453
• DOI: https://doi.org/10.1016/j.jtemb.2020.126453
• Keywords: Inorganic Chemistry; Molecular Medicine; Biochemistry
• Public URL: https://nottingham-repository.worktribe.com/output/3701989
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0946672X18307466