PURPOSE: The trace element iodine is a vital constituent of thyroid hormones. Iodine requirements increase during pregnancy, when even mild deficiency may affect the neurocognitive development of the offspring. Urinary iodine concentration (UIC) is the means of assessing iodine status in population surveys; a median UIC of 100-199 µg/L is deemed sufficient in a non-pregnant population. Milk is the main dietary source of iodine in the UK and Ireland. METHODS: We surveyed the iodine status of 903 girls aged 14-15 years in seven sites across the island of Ireland. Urine iodine concentration was measured in spot-urine samples collected between March 2014 and October 2015. Food group intake was estimated from iodine-specific food-frequency questionnaire. Milk-iodine concentration was measured at each site in summer and winter. RESULTS: The median UIC overall was 111 µg/L. Galway was the only site in the deficient range (median UIC 98 µg/L). All five of the Republic of Ireland sites had UIC ≤ 105 µg/L. In the two sites surveyed twice, UIC was lower in summer vs winter months [117 µg/L (IQR 76-165) vs 130 µg/L (IQR 91-194) (p < 0.01)]. Milk samples collected from Galway and Roscommon had a lower mean iodine concentration than those from Derry/Londonderry (p < 0.05). Milk intake was positively associated with UIC (p < 0.001). CONCLUSIONS: This is the largest survey of its kind on the island of Ireland, which currently has no iodine-fortification programme. Overall, the results suggest that this young female population sits at the low end of sufficiency, which has implications if, in future, they enter pregnancy with borderline status.
PURPOSE: The trace element iodine is a vital constituent of thyroid hormones. Iodine requirements increase during pregnancy, when even mild deficiency may affect the neurocognitive development of the offspring. Urinary iodine concentration (UIC) is the means of assessing iodine status in population surveys; a median UIC of 100-199 µg/L is deemed sufficient in a non-pregnant population. Milk is the main dietary source of iodine in the UK and Ireland. METHODS: We surveyed the iodine status of 903 girls aged 14-15 years in seven sites across the island of Ireland. Urine iodine concentration was measured in spot-urine samples collected between March 2014 and October 2015. Food group intake was estimated from iodine-specific food-frequency questionnaire. Milk-iodine concentration was measured at each site in summer and winter. RESULTS: The median UIC overall was 111 µg/L. Galway was the only site in the deficient range (median UIC 98 µg/L). All five of the Republic of Ireland sites had UIC ≤ 105 µg/L. In the two sites surveyed twice, UIC was lower in summer vs winter months [117 µg/L (IQR 76-165) vs 130 µg/L (IQR 91-194) (p < 0.01)]. Milk samples collected from Galway and Roscommon had a lower mean iodine concentration than those from Derry/Londonderry (p < 0.05). Milk intake was positively associated with UIC (p < 0.001). CONCLUSIONS: This is the largest survey of its kind on the island of Ireland, which currently has no iodine-fortification programme. Overall, the results suggest that this young female population sits at the low end of sufficiency, which has implications if, in future, they enter pregnancy with borderline status.
Authors: Oliver C Witard; Sarah C Bath; Mariana Dineva; Laury Sellem; Ana-Isabel Mulet-Cabero; Laura H van Dongen; Ju-Sheng Zheng; Carina Valenzuela; Benoit Smeuninx Journal: Front Nutr Date: 2022-02-10
Authors: Line Tang Møllehave; Marie Holm Eliasen; Ieva Strēle; Allan Linneberg; Rodrigo Moreno-Reyes; Ludmila B Ivanova; Zvonko Kusić; Iris Erlund; Till Ittermann; Endre V Nagy; Ingibjorg Gunnarsdottir; Jonathan Eli Arbelle; Aaron Milton Troen; Valdis Pīrāgs; Lisbeth Dahl; Alicja Hubalewska-Dydejczyk; Malgorzata Trofimiuk-Müldner; João Jacome de Castro; Mafalda Marcelino; Simona Gaberšček; Katja Zaltel; Manuel Puig-Domingo; Lluis Vila; Sofia Manousou; Helena Filipsson Nyström; Michael Bruce Zimmermann; Karen R Mullan; Jayne Valerie Woodside; Henry Völzke; Betina Heinsbæk Thuesen Journal: Endocr Connect Date: 2022-03-10 Impact factor: 3.335