{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,18]],"date-time":"2025-11-18T16:59:38Z","timestamp":1763485178472,"version":"3.45.0"},"reference-count":45,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2025,11,18]],"date-time":"2025-11-18T00:00:00Z","timestamp":1763424000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Foundation for Science and Technology","doi-asserted-by":"publisher","award":["UID\/06304\/2023","LA\/P\/0050\/2020"],"award-info":[{"award-number":["UID\/06304\/2023","LA\/P\/0050\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"FCT doctoral fellowship","doi-asserted-by":"publisher","award":["2022.12249.BD"],"award-info":[{"award-number":["2022.12249.BD"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background: Iodine is a micronutrient essential for the synthesis of thyroid hormones and crucial throughout life. Milk is potentially one of the major contributors to iodine intake in many countries, including Portugal, due to its consumption patterns. Objectives: This study characterizes iodine content seasonality in milk and plant-based milk alternatives commercially available in Portugal. Results: Milk products representing summer and winter seasonal pastures and plant-based alternatives were obtained from major Portuguese supermarkets. Iodine was quantified by the Sandell\u2013Kolthoff reaction in 146 winter and 142 summer milk products, as well as in 128 plant-based alternatives. Cow\u2019s milk contained relevant iodine levels (Md = 19.9, IQR = 9.9 \u00b5g\/100 mL), with no influence of thermal processing, fat or lactose content, season, or being organic and\/or from pasture. However, regional differences were observed. The iodine concentration in plant-based drinks was residual, except for four fortified products. Conclusions: This study provides evidence that milk is still a relevant source of iodine in Portugal, whereas most plant-based alternatives provide negligible iodine, unless fortified. Given shifts towards plant-based diets, monitoring iodine sources and adjusting health policies to fulfil nutritional requirements are pivotal to ensure iodine adequacy.<\/jats:p>","DOI":"10.3390\/nu17223606","type":"journal-article","created":{"date-parts":[[2025,11,18]],"date-time":"2025-11-18T16:49:51Z","timestamp":1763484591000},"page":"3606","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Mapping Iodine Sources for Human Nutrition in Portugal Considering Geography, Seasonality, and Processing: Milk and Plant-Based Milk Alternatives"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6758-7545","authenticated-orcid":false,"given":"Sarai Isabel","family":"Machado","sequence":"first","affiliation":[{"name":"Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0732-1571","authenticated-orcid":false,"given":"Ana","family":"Machado","sequence":"additional","affiliation":[{"name":"Laboratory of Hydrobiology and Ecology, Institute of Biomedical Sciences (ICBAS-UP), University of Porto, 4050-313 Porto, Portugal"},{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, 4450-208 Matosinhos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9637-6541","authenticated-orcid":false,"given":"Adriano A.","family":"Bordalo","sequence":"additional","affiliation":[{"name":"Laboratory of Hydrobiology and Ecology, Institute of Biomedical Sciences (ICBAS-UP), University of Porto, 4050-313 Porto, Portugal"},{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, 4450-208 Matosinhos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6512-996X","authenticated-orcid":false,"given":"Susana","family":"Roque","sequence":"additional","affiliation":[{"name":"Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6357-0615","authenticated-orcid":false,"given":"Nuno","family":"Borges","sequence":"additional","affiliation":[{"name":"Faculty of Nutrition and Food Sciences, University of Porto, 4150-180 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8866-368X","authenticated-orcid":false,"given":"Joana Almeida","family":"Palha","sequence":"additional","affiliation":[{"name":"Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1251","DOI":"10.1016\/S0140-6736(08)61005-3","article-title":"Iodine-deficiency disorders","volume":"372","author":"Zimmermann","year":"2008","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1017\/S0029665122002762","article-title":"The remarkable impact of iodisation programmes on global public health","volume":"82","author":"Zimmermann","year":"2023","journal-title":"Proc. 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