Publications by authors named "Inger Aakre"

29 Publications

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Iodine Nutrition and Iodine Supplement Initiation in Association with Thyroid Function in Mildly-to-Moderately Iodine-Deficient Pregnant and Postpartum Women.

J Nutr 2021 Oct;151(10):3187-3196

Seafood, Nutrition and Environmental State, Institute of Marine Research, Bergen, Norway.

Background: Whereas the adverse effects of severe iodine deficiency during pregnancy are well documented, the effects of mild-to-moderate deficiency are not well established.

Objectives: We aimed to explore whether iodine nutrition and timing of iodine supplement initiation are associated with thyroid function in pregnant and postpartum women.

Methods: In this cohort study, 137 pregnant women were enrolled and followed up at gestational weeks (GWs) 18 and 36, and 3 and 6 mo postpartum. Thyroid function tests [thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), and free thyroxine (fT4)], urinary iodine and creatinine concentration (UIC:Cr), and iodine intake (including iodine supplement use) were measured at each time point. The associations between thyroid hormone concentrations and UIC:Cr, iodine intakes, and iodine supplement use were estimated using multiple generalized estimating equation models.

Results: The median UIC at GW18 was 94 μg/L, indicating mild-to-moderate iodine deficiency. UIC:Cr (β; 95% CI) per 100 μg/g was negatively associated with fT3 (-0.191; -0.331, -0.051) and fT4 (-0.756; -1.372, -0.141) concentrations. Iodine intake (β; 95% CI) per 100 μg/d was positively associated with TSH (0.099; 0.022, 0.177), and negatively associated with fT3 (-0.084; -0.0141, -0.027) and fT4 (-0.390; -0.599, -0.182) concentrations. Compared with no use of supplement, those initiating an iodine-containing supplement prepregnancy and continuing through pregnancy had lower TSH (estimated means) (1.35 compared with 1.68 mIU/L, P = 0.021), and higher fT3 (4.48 compared with 4.28 pmol/L, P = 0.035) and fT4 (15.2 compared with 14.4 pmol/L, P = 0.024) concentrations.

Conclusions: Lower iodine availability during pregnancy and postpartum was associated with lower TSH, and higher fT3 and fT4 concentrations. The use of an iodine-containing supplement that was initiated prepregnancy and continuing through pregnancy was associated with lower TSH, and higher fT3 and fT4 concentrations, which may suggest improved thyroid function. These findings support the notion that optimization of iodine intake should start before pregnancy.This trial was registered at clinicaltrials.gov as NCT02610959.
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http://dx.doi.org/10.1093/jn/nxab224DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8485914PMC
October 2021

Metal Contents in Fish from the Bay of Bengal and Potential Consumer Exposure-The EAF-Nansen Programme.

Foods 2021 May 20;10(5). Epub 2021 May 20.

Seafood, Nutrition and Environmental State, Institute of Marine Research, P.O. Box 2029 Nordnes, 5817 Bergen, Norway.

Fish represent an important part of the Sri Lankan and Bangladeshi diet. However, fish is also a source of contaminants that may constitute a health risk to consumers. The aim of this study was to analyse the contents of arsenic, cadmium, mercury, and lead in 24 commonly consumed marine fish species from the Bay of Bengal and to assess the potential health risk associated with their consumption. Mercury and lead contents did not exceed the maximum limits for any of the sampled species, and consumer exposure from estimated daily consumption was assessed to be minimal for adults and children. Numerous samples exceeded the maximum limit for cadmium (58%), particularly those of small size (≤25 cm). However, consumer exposure was insignificant, and health assessment showed no risk connected to consumption. These data represent an important contribution to future risk/benefit assessments related to the consumption of fish.
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http://dx.doi.org/10.3390/foods10051147DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8160839PMC
May 2021

Commercially available kelp and seaweed products - valuable iodine source or risk of excess intake?

Food Nutr Res 2021 30;65. Epub 2021 Mar 30.

Department of Seafood and Nutrition, Institute of Marine Research, NO-5817 Bergen, Norway.

Background: Seaweeds and kelps, also known as macroalgae, have long been common in the East-Asian diet. During recent years, macroalgae have entered the global food market, and a variety of macroalgae products are now available for consumers. Some macroalgae species are known to be particularly rich in iodine, but little data regarding the iodine content of macroalgae-containing foods exists.

Objective: The aim of this research study was to analyse the iodine content in a large variety of commercially available macroalgae-containing foods and supplements and to evaluate whether such products are sources of adequate dietary iodine.

Design: Ninety-six different products were collected after surveying the Norwegian market for commercially available macroalgae products, collected from three categories: 1) wholefood macroalgae products ( = 43), 2) macroalgae-containing foods ( = 39), and 3) dietary supplements containing macroalgae ( = 14). All products were analysed for iodine content by inductively coupled plasma-mass spectrometry (ICP-MS).

Results: The iodine content in one portion of wholefood macroalgae products ranged from 128 to 62,400 μg. In macroalgae-containing foods, the iodine content ranged from 30 to 25,300 μg per portion, and in supplements it ranged from 5 to 5,600 μg per daily dose. The species with the highest analysed iodine content were oarweed, sugarkelp and kombu, with mean iodine levels of 7,800, 4,469 and 2,276 μg/g, respectively. For 54 products, the intake of one portion or dose would exceed the tolerable upper intake level (UL) for iodine.

Discussion And Conclusion: The iodine content in the included products was variable and for most products high, exceeding the tolerable upper intake level (UL) if consumed as a serving or portion size. The labelling of macroalgae species included, and declaration of iodine content, were inadequate or inaccurate for several products. As macroalgae-containing products are unreliable iodine sources, inclusion of such products in the diet may pose a risk of consuming excessive amounts of iodine.
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http://dx.doi.org/10.29219/fnr.v65.7584DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8035890PMC
March 2021

Vegans, Vegetarians and Pescatarians Are at Risk of Iodine Deficiency in Norway.

Nutrients 2020 Nov 20;12(11). Epub 2020 Nov 20.

Department of Nursing and Health Promotion, Faculty of Health Science, Oslo Metropolitan University, 0130 Oslo, Norway.

Low iodine intakes have been documented in different population groups in Norway. We aimed to assess iodine status, dietary intake, supplement and macroalgae use, and iodine knowledge in vegans, vegetarians and pescatarians. In this study, 115 vegans, 55 vegetarians and 35 pescatarians from the Oslo region of Norway, aged 18-60 years, participated. A spot urine sample was collected along with a dietary assessment of iodine intake, supplement and macroalgae use. The median urinary iodine concentration (MUIC) in vegans was 43 µg/L (moderate iodine deficiency), in vegetarians 67 µg/L and in pescatarians 96 µg/L (mild iodine deficiency). In multiple linear regression analysis, use of iodine supplements was one of the strongest predictors of UIC. About half of the participants had median 24-h iodine intakes below estimated average requirement (EAR) of 100 µg/day. Fifty percent had low knowledge score, while 27% had very low knowledge score. Vegans, vegetarians and possibly pescatarians in Norway, are unable to reach the recommended iodine intake merely from food and are dependent on iodine supplements. There is an urgent need for dietary guidance targeting vegans, vegetarians and pescatarians to avoid inadequate iodine intake in non-supplement users, as well as avoiding excess iodine intake in macroalgae users.
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http://dx.doi.org/10.3390/nu12113555DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7699510PMC
November 2020

Iodine Status and Thyroid Function in a Group of Seaweed Consumers in Norway.

Nutrients 2020 Nov 13;12(11). Epub 2020 Nov 13.

Department of Seafood and Nutrition, Institute of Marine Research, NO-5817 Bergen, Norway.

Seaweeds, or macroalgae, may be a good dietary iodine source but also a source of excessive iodine intake. The main aim in this study was to describe the iodine status and thyroid function in a group of macroalgae consumers. Two urine samples were collected from each participant ( = 44) to measure urinary iodine concentration (UIC) after habitual consumption of seaweed. Serum thyroid stimulating hormone (TSH), free thyroxine (fT), free triiodothyronine (fT), and peroxidase autoantibody (TPOAb), were measured in a subgroup ( = 19). A food frequency questionnaire and an iodine-specific 24 h recall were used to assess iodine intake and macroalgae consumption. The median (p25-p75) UIC was 1200 (370-2850) μg/L. Median (p25-p75) estimated dietary iodine intake, excluding macroalgae, was 110 (78-680) μg/day, indicating that seaweed was the major contributor to the iodine intake. TSH levels were within the reference values, but higher than in other comparable population groups. One third of the participants used seaweeds daily, and sugar kelp, winged kelp, dulse and laver were the most common species. Labelling of iodine content was lacking for a large share of the products consumed. This study found excessive iodine status in macroalgae consumers after intake of dietary seaweeds. Including macroalgae in the diet may give excessive iodine exposure, and consumers should be made aware of the risk associated with inclusion of macroalgae in their diet.
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http://dx.doi.org/10.3390/nu12113483DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7697291PMC
November 2020

Composition of nutrients, heavy metals, polycyclic aromatic hydrocarbons and microbiological quality in processed small indigenous fish species from Ghana: Implications for food security.

PLoS One 2020 12;15(11):e0242086. Epub 2020 Nov 12.

Institute of Marine Research, Bergen, Norway.

The triple burden of malnutrition is an incessant issue in low- and middle-income countries, and fish has the potential to mitigate this burden. In Ghana fish is a central part of the diet, but data on nutrients and contaminants in processed indigenous fish species, that are often eaten whole, are missing. Samples of smoked, dried or salted Engraulis encrasicolus (European anchovy), Brachydeuterus auritus (bigeye grunt), Sardinella aurita (round sardinella), Selene dorsalis (African moonfish), Sierrathrissa leonensis (West African (WA) pygmy herring) and Tilapia spp. (tilapia) were collected from five different regions in Ghana. Samples were analyzed for nutrients (crude protein, fat, fatty acids, several vitamins, minerals, and trace elements), microbiological quality (microbial loads of total colony counts, E. coli, coliforms, and Salmonella), and contaminants (PAH4 and heavy metals). Except for tilapia, the processed small fish species had the potential to significantly contribute to the nutrient intakes of vitamins, minerals, and essential fatty acids. High levels of iron, mercury and lead were detected in certain fish samples, which calls for further research and identification of anthropogenic sources along the value chains. The total cell counts in all samples were acceptable; Salmonella was not detected in any sample and E. coli only in one sample. However, high numbers of coliform bacteria were found. PAH4 in smoked samples reached high concentrations up to 1,300 μg/kg, but in contrast salted tilapia samples had a range of PAH4 concentration of 1 μg/kg to 24 μg/kg. This endpoint oriented study provides data for the nutritional value of small processed fish as food in Ghana and also provides information about potential food safety hazards. Future research is needed to determine potential sources of contamination along the value chains in different regions, identify critical points, and develop applicable mitigation strategies to improve the quality and safety of processed small fish in Ghana.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0242086PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7660496PMC
January 2021

Variation in Nutrient Composition of Seafood from North West Africa: Implications for Food and Nutrition Security.

Foods 2020 Oct 21;9(10). Epub 2020 Oct 21.

Institute of Marine Research, 5817 Bergen, Norway.

Fish and seafood may play an important role for nutrition and food security as they contain essential vitamins, minerals, and essential fatty acids. The aim of this study was to describe the nutrient composition, including fatty acids, amino acids, vitamins, and minerals, in commonly consumed fish species (fillet- and whole fish samples) sampled off the Northwest African coast. Furthermore, we assessed the species' contributions to the recommended nutrient intake (RNI) values from the World Health Organization (WHO). Samples of commercially important fish species () were collected using trawling on the R/V Dr. Fridtjof Nansen in May 2017 and analyzed for nutrients at the Institute of Marine Research as individual and composite samples. All the analyzed fish species were good dietary sources of several vitamins and minerals and whole fish were substantially more nutrient dense than fillet samples, especially with regard to vitamin A, iodine, zinc, calcium, and iron. Including 100 g of sardine or anchovy (whole fish) in the diet, would contribute substantially to the RNI for vitamin B, vitamin D and vitamin A, EPA and DHA as well as the minerals iodine, zinc, and calcium. This study shows that fish consumed with skin, bone, and viscera may be very nutrient dense and important for local food and nutrition security.
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http://dx.doi.org/10.3390/foods9101516DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7590009PMC
October 2020

Sampling protocol for the determination of nutrients and contaminants in fish and other seafood - The EAF-Nansen Programme.

MethodsX 2020 12;7:101063. Epub 2020 Sep 12.

Institute of Marine Research, P.O. Box 2029 Nordnes, 5817 Bergen, Norway.

Seafood plays a central role in global food and nutrition security. However, there is a lack of data on the concentration of nutrients and contaminants in fish and other seafood, especially in low- and middle-income countries. In order to assess the potential risks and benefits associated with seafood intake, reliable and up-to-date food composition data is crucial. The quality of food composition data is affected by several factors, such as sampling protocols and the suitability and quality of the methods applied for sample preparation and analysis. In this paper, we describe the sampling methodology and protocols related to the sampling of fish and other seafood and the corresponding analytical methods used to analyse the nutrient and contaminant content of such species. For nutrients, the determination of protein, fat, ash, energy, fatty acids, cholesterol, and amino acids is described, in addition to analyses for determination of the vitamin and mineral content in fish and other seafood. For contaminants, analyses for the determination of organic pollutants and microplastics are described. The methodology described in this paper is used for sampling data through scientific surveys in low- and middle-income countries with research vessel under the EAF-Nansen Programme. The Programme aims to improve knowledge on the nutritional composition of fish and ensure the fish is safe to consume.•In this paper, we describe the sampling protocols used for sampling fish and other seafood during scientific surveys under the EAF-Nansen Programme.•This paper describes the methodology and quality control for analysing nutrients and contaminants in fish and other seafood.
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http://dx.doi.org/10.1016/j.mex.2020.101063DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7502570PMC
September 2020

Fatty Acid Reference Intervals in Red Blood Cells among Pregnant Women in Norway-Cross Sectional Data from the 'Little in Norway' Cohort.

Nutrients 2020 Sep 25;12(10). Epub 2020 Sep 25.

Institute of Marine Research, 1870 Nordnes, N-5817 Bergen, Norway.

There is a growing interest in determining fatty acid reference intervals from pregnancy cohort, especially considering the lack of reference values for pregnant women in the literature and the generalized misconception of equating reference intervals for nonpregnant women as equivalent to pregnant women. Seafood and supplements are important dietary sources for the omega-3 long-chain polyunsaturated fatty acids (ω-3 LCPUFA), such as eicosapentaenoic acid (EPA, 20:5ω-3), docosapentaenoic acid (DPA, 22:55ω-3), and docosahexaenoic acid (DHA, 22:6ω-3). Sufficient intake of EPA and DHA is vital during pregnancy for the development of the fetus, as well as for maintaining adequate levels for the mother. This study describes the fatty acid status and suggests reference values and cut-offs for fatty acids in red blood cells (RBC) from pregnant women ( = 247). An electronic food frequency questionnaire (e-FFQ) mapped the dietary habits of the participants, and gas chromatography was used to determine the fatty acid levels in RBC. The association between e-FFQ variables and fatty acid concentrations was established using a principal component analysis (PCA). Twenty-nine-point-one percent (29.1%) of the participants reported eating seafood as dinner according to the Norwegian recommendations, and they added in their diet as well a high percentage (76.9%) intake of ω-3 supplements. The concentration levels of fatty acids in RBC were in agreement with those reported in similar populations from different countries. The reference interval 2.5/97.5 percentiles for EPA, DPA, DHA were 0.23/2.12, 0.56/2.80, 3.76/10.12 in relative concentration units (%), and 5.99/51.25, 11.08/61.97, 64.25/218.08 in absolute concentration units (µg/g), respectively. The number of participants and their selection from all over Norway vouch for the representativeness of the study and the validity of the proposed reference values, and therefore, the study may be a useful tool when studying associations between fatty acid status and health outcome in future studies. To the best of our knowledge, this is the first PCA study reporting a direct association between ω-3 LCPUFA and intake of seafood and ω-3 supplements in a pregnancy cohort.
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http://dx.doi.org/10.3390/nu12102950DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7601079PMC
September 2020

Effects of Two Weekly Servings of Cod for 16 Weeks in Pregnancy on Maternal Iodine Status and Infant Neurodevelopment: Mommy's Food, a Randomized-Controlled Trial.

Thyroid 2021 02 8;31(2):288-298. Epub 2020 Sep 8.

Seafood, Nutrition and Environmental State, Institute of Marine Research, Bergen, Norway.

Mild-to-moderate iodine deficiency is still present in many countries, particularly in pregnant women. Observational studies suggest that mild-to-moderate iodine deficiency during pregnancy may be associated with impaired thyroid function and child neurodevelopment. Randomized-controlled food trials to increase iodine status are scarce. We assessed the impact of an increased intake of cod during pregnancy on maternal iodine status and infant neurodevelopment. In this randomized-controlled trial, pregnant women in Bergen, Norway, recruited through Haukeland University Hospital, were randomly assigned (1:1) to an intervention of 200 g of cod twice a week for 16 weeks (gestational week 20-36) or to continue with their standard diet (control group). Randomization was done by lottery. Primary outcome was urinary iodine concentration (UIC) (spot samples from six consecutive days) measured postintervention. Secondary outcome was infant neurodevelopment assessed by the cognitive, language, and motor scales of the third edition (Bayley-III) at 11 months of age. In addition, maternal thyroid function was measured (thyrotropin [TSH], free triiodothyronine [fT3], free thyroxine [fT4]) at baseline and postintervention. Between January 2016 until February 2017, 137 women were recruited. Postintervention UIC was higher in the intervention group ( = 61) [median (interquartile range, IQR) 98 (64-145) μg/L], compared with control ( = 61) [median (IQR) 73 (52-120) μg/L] ( = 0.028), also after adjusting for baseline UIC ( = 0.048). Infants of mothers in the intervention group had a lower cognitive composite score on the Bayley-III compared with the control group ( = 0.045). There were no group differences in the Bayley III language- or motor composite scores. Maternal thyroid hormones (TSH, fT3, fT4) did not differ between the groups postintervention. Increased cod intake during pregnancy improved the iodine status in women with mild-to-moderate iodine deficiency, however, did not affect thyroid function. The negative effect on cognition should be followed up to assess whether this is a stable effect over time. More studies are warranted to enable good health advice on iodine nutrition in pregnancy. ClinicalTrials.gov NCT02610959. Registered November 20, 2015.
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http://dx.doi.org/10.1089/thy.2020.0115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7891220PMC
February 2021

Iodine status during pregnancy and at 6 weeks, 6, 12 and 18 months post-partum.

Matern Child Nutr 2021 01 29;17(1):e13050. Epub 2020 Jun 29.

Department of Seafood, Nutrition and Environmental State, Institute of Marine Research, Bergen, Norway.

Iodine deficiency during pregnancy and in the post-partum period may lead to impaired child development. Our aim is to describe iodine status longitudinally in women from pregnancy until 18 months post-partum. Furthermore, we explore whether iodine status is associated with dietary intake, iodine-containing supplement use and breastfeeding status from pregnancy until 18 months post-partum. We also assess the correlation between maternal iodine status 18 months post-partum and child iodine status at 18 months of age. Iodine status was measured by urinary iodine concentration (UIC) during pregnancy (n = 1,004), 6 weeks post-partum (n = 915), 6 months post-partum (n = 849), 12 months post-partum (n = 733) and 18 months post-partum (n = 714). The toddlers' UIC was assessed at 18 months of age (n = 416). Demographic variables and dietary data (food frequency questionnaire) were collected during pregnancy, and dietary data and breastfeeding practices were collected at all time points post-partum. We found that iodine status was insufficient in both pregnant and post-partum women. The UIC was at its lowermost 6 weeks post-partum and gradually improved with increasing time post-partum. Intake of milk and use of iodine-containing supplements significantly increased the odds of having a UIC above 100 μg/L. Neither the mothers' UIC, vegetarian practice, nor exclusion of milk and dairy products were associated with the toddlers UIC 18 months post-partum. Women who exclude milk and dairy products from their diets and/or do not use iodine-containing supplements may be at risk of iodine deficiency. The women possibly also have an increased risk of thyroid dysfunction and for conceiving children with nonoptimal developmental status.
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http://dx.doi.org/10.1111/mcn.13050DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7729798PMC
January 2021

Nutrient Composition of Demersal, Pelagic, and Mesopelagic Fish Species Sampled Off the Coast of Bangladesh and Their Potential Contribution to Food and Nutrition Security-The EAF-Nansen Programme.

Foods 2020 Jun 3;9(6). Epub 2020 Jun 3.

Institute of Marine Research, P.O. Box 2029 Nordnes, 5817 Bergen, Norway.

Fish is a major part of the Bangladeshi diet, but data on the nutrient composition of marine fish species are sparse. Mesopelagic fish may be a new potential resource of food and nutrients; however, nutrient composition data are lacking. The aim of this study was to provide nutrient composition data of fish species sampled off the coast of Bangladesh and determine their potential contribution to recommended nutrient intakes (RNI). Seven species from the pelagic, mesopelagic, and demersal zones were sampled from the coast of Bangladesh with Dr. Fridtjof Nansen in 2018. Three pooled samples containing 15-840 individuals from each species were analysed at the Institute of Marine Research, Norway. The demersal species contained substantially lower concentrations of nearly all nutrients, whereas the mesopelagic species generally were more nutrient dense. All species, except for the demersal species Bombay duck (9% dry matter), were found to contribute ≥100% to the RNI of vitamin B, eicosapentaenoic acid, docosahexaenoic acid, and selenium. All species, except for the demersal fish species, contributed ≥25% to the RNI of six or more nutrients. The data presented in this paper are an important contribution to the Bangladeshi food composition table and contribute to the understanding of fish as an important source of micronutrients.
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http://dx.doi.org/10.3390/foods9060730DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7353586PMC
June 2020

Mercury, lead, arsenic, and cadmium in Norwegian seafood products and consumer exposure.

Food Addit Contam Part B Surveill 2020 Jun 24;13(2):99-106. Epub 2020 Mar 24.

Seafood, Nutrition and Environmental State, Institute of Marine Research , Bergen, Norway.

Seafood can be a source of contaminants, which may raise health concerns. The aim of this study was to analyse the levels of inorganic contaminants in commercially available seafood products and assess consumer exposure. Commercially available samples were collected from 2015-2018 and analysed as composite samples for mercury, lead, arsenic, and cadmium, using accredited methods. Levels of cadmium, lead, and arsenic were low and human exposure of these metals would be minimal from consumption of the analysed seafood products. Mercury levels were well below the EU maximum limit for mercury in fish. However, children, who are high consumers, might be at risk of exceeding the tolerable weekly intake for methyl mercury, when eating products with the highest mercury levels. The collected data can be used for future risk-benefit assessments as intake of processed seafood products represent a large proportion of the populations' seafood intake in Europe.
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http://dx.doi.org/10.1080/19393210.2020.1735533DOI Listing
June 2020

Validation and reproducibility of a new iodine specific food frequency questionnaire for assessing iodine intake in Norwegian pregnant women.

Nutr J 2019 10 29;18(1):62. Epub 2019 Oct 29.

Institute of Marine Research (IMR), 5817, Bergen, Norway.

Background: Iodized salt is not mandatory in Norway, and the permitted level of iodine in table salt is low (5 μg/g). Thus, milk and dairy products, fish and eggs are the main dietary sources of iodine in Norway. Mild-to-moderate iodine deficiency in pregnant women has been described in several European countries, including Norway. There are few validated tools available to assess iodine intake in an efficient manner. The aim of the current study was to assess the validity and reproducibility of a new iodine-specific food frequency questionnaire (I-FFQ) in Norwegian pregnant women.

Methods: An I-FFQ consisting of a total of 60 food items and the use of supplements was developed to assess iodine intake and was administrated to 137 pregnant women at gestational week 18-19. Reference methods were a structured 6-days iodine specific food diary, urinary iodine concentration (UIC) (pooled sample of spot UIC from six consecutive days), and thyroid function tests. Correlation analyses, Cohen's weighted kappa, Bland-Altman plots, and linear regression analyses were used to assess validity. Reproducibility of the I-FFQ was assessed in a subgroup (n = 47) at gestational week 35-36.

Results: There was a strong correlation between estimated iodine intake from the I-FFQ and food diary (r = 0.62, P < 0.001) and an acceptable correlation between the I-FFQ and UIC (r = 0.21, P = 0.018). There was no significant association between the I-FFQ and thyroid function tests. The I-FFQ estimated higher iodine intake compared to the food diary with a mean absolute difference 33 μg/day. The limits of agreement from the Bland-Altman plots were large, however few participants fell outside the limits of agreement (5.2-6.5%). There was no difference between the estimated iodine intake from the I-FFQ assessed at gestational week 18-19, and gestational week 35-36 (P = 0.866), and there was a strong correlation between the two time points (r = 0.63, P < 0.001).

Conclusion: In summary, this study suggests that the I-FFQ can be used as a valid tool to estimate and rank iodine intake among Norwegian pregnant women. We further suggest that this I-FFQ may also be valid in other populations with similarly dietary patterns and where salt is not iodized.

Trial Registration: The study is registered in ClinicalTrials.gov (NCT02610959).
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http://dx.doi.org/10.1186/s12937-019-0489-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6821006PMC
October 2019

New data on nutrient composition in large selection of commercially available seafood products and its impact on micronutrient intake.

Food Nutr Res 2019 8;63. Epub 2019 Jul 8.

Food Security and Nutrition, Institute of Marine Research, Bergen, Norway.

Background: Most foods, including seafood, undergo some sort of processing as an integrated part of the global food industry. The degree of processing depends on the type of product produced. Processed seafood products are an important part of the diet; thus, knowledge of nutrient content in seafood products is of great importance.

Objective: The aim of this study was to describe the content of selected nutrients in commercially available and market representative seafood products purchased from 3 different years.

Methods: Seafood products from 2015 ( = 16), 2017 ( = 35), and 2018 ( = 35) were analyzed as composite samples for macro- and micronutrients using accredited methods at the Institute of Marine Research in Norway.

Results: This study confirms that seafood products are good sources of several key nutrients, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), vitamin D, vitamin B12, iodine, and selenium. Fatty fish products had the highest content of EPA, DHA, and vitamin D, while lean fish products had the highest content of vitamin B12 and minerals. However, some lean fish products, such as one portion of fish au gratin or fish cakes, also proved as good sources of EPA, DHA, and vitamin D, and contributed substantially to the recommended intake. Variations in nutrients were seen both within the same product category and between the same product category from different years.

Conclusions: These data give valuable insights into seafood products as a source of essential micronutrients and highlight the importance of these products for nutrition and health.
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http://dx.doi.org/10.29219/fnr.v63.3573DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6642616PMC
July 2019

High iodine content in local animal milk and risk of exceeding EFSA upper intake level for iodine among Saharawi women.

PLoS One 2019 15;14(2):e0212465. Epub 2019 Feb 15.

Department of Nursing and Health Promotion, Faculty of Health Sciences, OsloMet - Oslo Metropolitan University, Oslo, Norway.

Excessive iodine intake is a major public health problem in the Saharawi refugee camps in Algeria, where animal milk is an important source of iodine. The purpose of this study was to assess the association between iodine concentrations in locally produced animal milk and in animal drinking water and further to assess the risk of exceeding European Food Safety Authority (EFSA) tolerable upper intake level for iodine (600 μg/d) among Saharawi women. In 2009 and 2010, 202 milk samples from goats and sheep and 52 milk samples from camel were collected. Iodine in milk was determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). In addition, iodine in 56 water samples from the general water system and 54 water samples from wells, was determined by modified Sandell-Kolthoff reaction. Animal milk is generally consumed mixed with water. The median (min, max) iodine intake from goat/sheep milk mixed with water in camps with high iodine content in human drinking water was 284 (57, 2889) μg/d and 19% of participants exceeded EFSA upper intake level for iodine. The median (min, max) iodine intake from camel milk mixed with water in all camps was 2100 (210, 11100) and 47% of participants exceeded the EFSA upper intake level. The median (min, max) iodine content in goat/sheep milk from camps with moderate and high iodine content in water was 507 (101, 4791) μg/L and 1612 (487, 9323) μg/L, respectively (p < 0.001). The iodine content in goat/sheep milk was positively associated with iodine content in animal drinking water (regression coefficient, B 5.71, 95% CI 4.03, 7.39). In conclusion, consumption of camel milk and living in camps with high water iodine content increased the risk of exceeding the EFSA upper intake level for iodine. We suggest that purified water for both human and animal consumption should be provided.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0212465PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6377136PMC
November 2019

Sufficient iodine status among Norwegian toddlers 18 months of age - cross-sectional data from the Little in Norway study.

Food Nutr Res 2018 25;62. Epub 2018 Oct 25.

Food Security and Nutrition, Institute of Marine Research, Bergen, Norway.

Background: Inadequate iodine intake has been identified in several population groups in the Nordic countries over the past years; however, studies of iodine status in infants and toddlers are scarce.

Objective: The aim of this study is to evaluate the iodine status and dietary iodine sources among 18-month-old toddlers from Norway.

Methods: Cross-sectional and country representative data from the Little in Norway study were used. All children who had given a spot urine sample at 18 months age were included ( = 416). Urinary iodine concentration (UIC) was determined by inductively coupled plasma mass-spectrometry. Dietary habits and supplement use were measured by a food frequency questionnaire.

Results: Median (25th-75th percentiles [p25-p75]) UIC was 129 (81-190) μg/L while estimated median (p25-p75) habitual iodine intake was 109 (101-117) μg/day. None of the children were below the estimated average requirement (EAR) of 65 μg/day or above the upper intake level of 180 μg/day. There were no differences in either UIC or estimated habitual iodine intake between different geographic areas in Norway. Milk was the most important iodine source, contributing an estimated 70% to the total iodine intake, while other foods rich in iodine such as seafood and enriched baby porridge contributed about 30%.

Conclusions: The iodine status among 18-month-old toddlers from different geographic areas in Norway was sufficient, indicated by a median UIC above the WHO cutoff of 100 μg/L. This was further supported by the estimated habitual iodine intake, where none of the participants were below the EAR. Milk was an important iodine source in this age group; thus children with a low intake might be at risk of insufficient iodine intake.
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http://dx.doi.org/10.29219/fnr.v62.1443DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6294835PMC
October 2018

Trace Element Concentrations in Drinking Water and Urine among Saharawi Women and Young Children.

Toxics 2018 Jul 21;6(3). Epub 2018 Jul 21.

Department of Nursing and Health Promotion, Faculty of Health Sciences, OsloMet-Oslo Metropolitan University, 0310 Oslo, Norway.

Poor water quality has been reported along with a variety of negative health outcomes in the Saharawi refugee camps in Algeria. We assessed the concentration of elements in drinking water and urine in refugee women and children. Twenty-four samples of distributed public drinking water were collected, along with urine samples from 77 women and 296 children. Using inductively coupled plasma mass spectrometry, we analyzed water and urine for 31 and 10 elements, respectively. In addition, the water samples were analyzed for five anions by ion-exchange chromatography. Data were described according to two areas: zone 1 with purified water and water with naturally better quality, and zone 2 with only partially purified water. Most elements in drinking water had significantly higher concentration in zone 2 compared with zone 1. Sodium, chloride, nitrite, and nitrate were the parameters that exceeded the WHO Guidelines for Drinking Water Quality. Among both women and children, urinary concentration of vanadium, arsenic, selenium, lead, iodine, and uranium exceeded reference values, and most of the elements were significantly higher in zone 2 compared to zone 1. Even though water purification in the Saharawi refugee camps has increased during the last years, some elements are still exceeding the WHO guidelines for drinking water quality. Moreover, urinary exposure of some elements exceeded reference values from the literature. Further effort should be made to improve the water quality among the Saharawi refugees.
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http://dx.doi.org/10.3390/toxics6030040DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6160998PMC
July 2018

Suboptimal Iodine Status and Low Iodine Knowledge in Young Norwegian Women.

Nutrients 2018 Jul 21;10(7). Epub 2018 Jul 21.

Institute of Marine Research (IMR), P.O. Box 1870 Nordnes, 5817 Bergen, Norway.

Previous studies have documented mild to moderate iodine deficiency in pregnant and lactating women in Norway. This study focused on non-pregnant young women because their future children may be susceptible to the adverse effects of iodine deficiency. We assessed urinary iodine concentration (UIC), iodine intake from food and supplements, and iodine knowledge in 403 non-pregnant women, mainly students, aged 18⁻30 years. Iodine concentration was measured in spot urine samples analyzed by inductively coupled plasma mass spectrometry and iodine intake was calculated from a self-reported food frequency questionnaire. Knowledge about iodine was collected through the self-administered, paper-based questionnaire. Median (p25⁻p75) UIC was 75 (42⁻130) µg/L and 31% had UIC < 50 µg/L. Habitual iodine intake was 100 (69⁻136) µg/day. In multiple regression models, supplemental iodine, use of thyroid medication, and iodine intake from food were positively associated with UIC, while vegetarian practice was negatively associated, explaining 16% of the variance. Approximately 40% of the young women had low iodine knowledge score and no differences were found between women in different study programs. Young women in Norway are mild to moderately iodine-deficient, and public health strategies are needed to improve and secure adequate iodine status.
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http://dx.doi.org/10.3390/nu10070941DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6073112PMC
July 2018

Suboptimal Iodine Status among Pregnant Women in the Oslo Area, Norway.

Nutrients 2018 Feb 28;10(3). Epub 2018 Feb 28.

Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo 0403, Norway.

Norway has been considered iodine replete for decades; however, recent studies indicate reemergence of inadequate iodine status in different population groups. We assessed iodine status in pregnant women based on urinary iodine concentration (UIC), urinary iodine excretion (UIE), and iodine intake from food and supplements. In 804 pregnant women, 24-h iodine intakes from iodine-rich foods and iodine-containing supplements were calculated. In 777 women, iodine concentration was measured in spot urine samples by inductively coupled plasma/mass spectrometry (ICP-MS). In addition, 49 of the women collected a 24-h urine sample for assessment of UIE and iodine intake from food frequency questionnaire (FFQ). Median UIC was 92 µg/L. Fifty-five percent had a calculated iodine intake below estimated average requirement (EAR) (160 µg/day). Iodine intake from food alone did not provide the amount of iodine required to meet maternal and fetal needs during pregnancy. In multiple regression models, hypothyroidism, supplemental iodine and maternal age were positively associated with UIC, while gestational age and smoking were negatively associated, explaining 11% of the variance. This study clearly shows that pregnant women in the Oslo area are mild to moderate iodine deficient and public health strategies are needed to improve and secure adequate iodine status.
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http://dx.doi.org/10.3390/nu10030280DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5872698PMC
February 2018

Excessive iodine status among Saharawi refugees.

J Trace Elem Med Biol 2018 01 22;45:48-49. Epub 2017 Sep 22.

Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University, College of Applied Sciences, 0310 Oslo, Norway.

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http://dx.doi.org/10.1016/j.jtemb.2017.09.015DOI Listing
January 2018

Associations between thyroid dysfunction and developmental status in children with excessive iodine status.

PLoS One 2017 22;12(11):e0187241. Epub 2017 Nov 22.

Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University College, Oslo, Norway.

Background And Objective: Adequate iodine status and normal thyroid hormone synthesis are important for optimal child development. In this study, we explored whether young children's developmental status is associated with thyroid dysfunction in an area of chronic excessive iodine exposure.

Methods: We included 298 children between 18 and 48 months of age residing in Algerian refugee camps. Early child development was measured using the Ages and Stages Questionnaires, third edition (ASQ-3), consisting of five domains: Communication, Gross Motor, Fine Motor, Problem Solving and Personal-Social. Due to poor discriminatory ability in the Gross Motor domain, the total ASQ-3 scores were calculated both including and excluding this domain. Urinary iodine concentration (UIC), thyroid hormones (TSH, FT3 and FT4), thyroid antibodies and serum thyroglobulin (Tg) were measured.

Results: The median UIC was 451.6 μg/L, and approximately 72% of the children had a UIC above 300 μg/L. Furthermore, 14% had thyroid disturbances, of whom 10% had TSH outside the reference range. Children with thyroid disturbances and TSH outside the reference ranges had lower odds of being among the 66% highest total ASQ scores, with adjusted odds ratios (95% CI) of 0.46 (0.23, 0.93) and 0.42 (0.19, 0.94), respectively.

Conclusion: We found an association between thyroid dysfunction and poorer developmental status among children with excessive iodine intake. The high iodine intake may have caused the thyroid dysfunction and hence the delayed developmental status; however, other influential factors cannot be excluded. Optimal child development is important for a sustainable future. With iodine excess being an increasing problem globally, this subject should be further explored.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0187241PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5699829PMC
December 2017

Suboptimal Iodine Concentration in Breastmilk and Inadequate Iodine Intake among Lactating Women in Norway.

Nutrients 2017 Jun 22;9(7). Epub 2017 Jun 22.

Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo 0403, Norway.

Breastfed infants depend on sufficient maternal iodine intake for optimal growth and neurological development. Despite this, few studies have assessed iodine concentrations in human milk and there is currently no published data on iodine status among lactating women in Norway. The aim of this study was to assess iodine concentrations in breast milk (BMIC) in lactating women and estimate iodine intake. Five Mother and Child Health Centres in Oslo were randomly selected during 2016, and 175 lactating women between 2nd and 28th weeks postpartum participated. Each of the women provided four breastmilk samples which were pooled and analysed for iodine concentrations. Participants also provided information on iodine intake from food and supplements covering the last 24 h and the habitual iodine intake (food frequency questionnaire). The median (p25, p75 percentiles) BMIC was 68 (45, 98) µg/L and 76% had BMIC <100 µg/L. Only 19% had taken an iodine-containing supplement during the last 24 h. The median 24 h iodine intake from food (p25, p75) was 121 (82, 162) µg/day and the total intake (food and supplements) was 134 (95, 222) µg/day. The majority of lactating women had suboptimal BMIC and inadequate intake of iodine from food and supplements.
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http://dx.doi.org/10.3390/nu9070643DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5537763PMC
June 2017

Knowledge about Iodine in Pregnant and Lactating Women in the Oslo Area, Norway.

Nutrients 2017 May 13;9(5). Epub 2017 May 13.

Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University College of Applied Sciences, 0130 Oslo, Norway.

Background: Lack of knowledge about iodine may be a risk factor for iodine deficiency in pregnant and lactating women. The aim of this study was to assess knowledge about iodine and predictors of iodine knowledge scores among pregnant and lactating women. The study also examined whether iodine knowledge scores were associated with iodine status.

Methods: A cross-sectional study was performed on 804 pregnant women and 175 lactating women from 18 to 44 years of age in 2016 in the Oslo area, Norway. Knowledge about iodine was collected through a self-administered, paper-based questionnaire. Iodine concentrations in urine and breast milk were measured using an inductively coupled plasma mass spectrometer (ICPMS).

Results: 74% of the pregnant women and 55% of the lactating women achieved none to low iodine knowledge scores. Higher educated pregnant women and those who had received information about iodine had significantly higher knowledge scores. In lactating women, increased age was associated with higher knowledge scores. Knowledge scores were not associated with participants' iodine status.

Conclusion: This study revealed a lack of knowledge about the importance of iodine in pregnant and lactating women, as well as about the most important dietary sources. Public education initiatives are required to increase the awareness about iodine in these population groups.
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http://dx.doi.org/10.3390/nu9050493DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452223PMC
May 2017

Infant feeding practices in the Saharawi refugee camps Algeria, a cross-sectional study among children from birth to six months of age.

Int Breastfeed J 2016 28;12. Epub 2017 Jan 28.

Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University College, PB 4 St. Olavs plass, 0130 Oslo, Norway.

Background: Appropriate breastfeeding and infant feeding practices are crucial to a child's growth and development. The objective of this paper is to describe breastfeeding and general feeding practices and the nutrition status among children from birth to 6 months of age, in the Saharawi refugee camps located in Algeria.

Methods: A cross-sectional study was carried out among 111 lactating mothers with infants from birth to 6 months of age. Data regarding breastfeeding practices and a 24 h dietary recall for the infants were collected to assess the World Health Organization's (WHO) indicators for infant and young child feeding. For exclusive and predominant breastfeeding, age disaggregation for each month was applied to the data. Background characteristics from the mothers and infants were collected, together with anthropometrical measures. We explored predictors for breastfeeding and nutrition status in multiple regression models.

Results: In total 13.8%, 8.2% and 16.5% of the infants were stunted, wasted and underweight, respectively. Approximately 65% initiated breastfeeding within 1 h after birth and 11.7 and 21.6% were exclusively or predominantly breastfed less than 6 months. The most commonly given solid foods were dates (27.0%) and bread (10.8%). In multiple regression models, initiation of breastfeeding within 1 h after birth gave increased probability of exclusive or predominant breastfeeding. Giving birth at home as opposed to in a hospital and increasing number of children gave increased probability of initiating breastfeeding early. Exclusive or predominant breastfeeding seemed to protect against underweight and wasting.

Conclusions: Exclusively or predominant breastfeeding was low among Saharawi refugee infants. Wasting and underweight was common and more likely to occur if the infants were not exclusively or predominantly breastfed. These findings support the current international breastfeeding recommendations, and suggest that there is an urgent need for promoting infant feeding practices in the Sahara refugee camps.
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http://dx.doi.org/10.1186/s13006-016-0098-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5273854PMC
January 2017

Thyroid Function among Breastfed Children with Chronically Excessive Iodine Intakes.

Nutrients 2016 Jun 28;8(7). Epub 2016 Jun 28.

Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University College, 0130 Oslo, Norway.

Iodine excess may impair thyroid function and trigger adverse health consequences for children. This study aims to describe iodine status among breastfed infants with high iodine exposure in the Saharawi refugee camps Algeria, and further assess thyroid function and iodine status among the children three years later. In 2010, a cross-sectional study among 111 breastfed children aged 0-6 months was performed (baseline study). In 2013, a second cross-sectional study (follow-up study) was conducted among 289 children; 213 newly selected and 76 children retrieved from baseline. Urinary iodine concentration (UIC) and breast milk iodine concentration (BMIC) were measured at baseline. UIC, thyroid hormones and serum thyroglobulin (Tg) were measured at follow-up. At baseline and follow-up, 88% and 72% had excessive iodine intakes (UIC ≥ 300 µg/L), respectively. At follow-up, 24% had a thyroid hormone disturbance and/or elevated serum Tg, including 9% with subclinical hypothyroidism (SCH), 4% with elevated fT3 and 14% with elevated Tg. Children with SCH had poorer linear growth and were more likely to be underweight than the children without SCH. Excessive iodine intakes and thyroid disturbances were common among children below four years of age in our study. Further, SCH seemed to be associated with poor growth and weight.
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http://dx.doi.org/10.3390/nu8070398DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4963874PMC
June 2016

Development of thyroid dysfunction among women with excessive iodine intake--A 3-year follow-up.

J Trace Elem Med Biol 2015 30;31:61-6. Epub 2015 Mar 30.

Department of Health Nutrition and Management, Faculty of Health Sciences, Oslo and Akershus University College, Oslo, Norway.

Objectives: Thyroid dysfunction can be a result of excessive iodine intake, which may have adverse health consequences, particularly for women in fertile age. In 2010, we conducted a cross-sectional study among lactating women with excessive iodine intake in the Saharawi refugee camps in Algeria and found a high prevalence of thyroid dysfunction. Three years later, we conducted a follow-up study to monitor the iodine situation and explore whether thyroid dysfunction still was highly prevalent when the women no longer were post-partum. None of the women were treated for hyper- or hypothyroidism between baseline and follow-up.

Methods: In 2013, we were able to recapture 78 of the 111 women from the baseline. Thyroid hormones and antibodies were measured in serum and thyroid size was assessed by palpation. Urinary iodine concentration (UIC) and drinking water iodine concentration were measured.

Results: The overall prevalence of thyroid dysfunction and/or positive antibodies was 34.3% and was not significantly changed from baseline. Of the non-pregnant women we reexamined, 17 had hypo- or hyperthyroidism in 2010; among these, 12 women still had abnormal thyroid function at follow-up. In addition, we found 9 new cases with marginally abnormal thyroid function. Women with thyroid dysfunction and/or positive antibodies had significantly higher BMI and thyroglobulin than women with normal thyroid function. We also found that women with high breast milk iodine concentration (BMIC) at baseline had more thyroid dysfunction at follow-up than the women with lower BMIC at baseline.

Conclusions: At follow-up, the prevalence of thyroid dysfunction was still high and had not changed during the 3 years between studies and from a postpartum period. The women still had a high iodine intake indicated by high UIC. Breast milk iodine concentration from baseline predicted thyroid dysfunction at follow-up.
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http://dx.doi.org/10.1016/j.jtemb.2015.03.004DOI Listing
February 2016

Excessive iodine intake and thyroid dysfunction among lactating Saharawi women.

J Trace Elem Med Biol 2015 6;31:279-84. Epub 2014 Oct 6.

Department of Health Nutrition and Management, Faculty of Health Sciences, Oslo and Akershus University College, Oslo, Norway.

Objectives: Excessive iodine intake may lead to thyroid dysfunction, which may be particularly harmful during pregnancy and lactation. The main objective was to describe iodine status and the prevalence of thyroid dysfunction among lactating women in areas with high iodine (HI) and very high iodine (VHI) concentrations in drinking water.

Design And Methods: A cross-sectional survey was performed among 111 lactating women in the Saharawi refugee camps, Algeria. Breast milk iodine concentration (BMIC), urinary iodine concentration (UIC) and the iodine concentration in the most commonly consumed foods/drinks were measured. A 24-h dietary recall was used to estimate iodine intake. Thyroid hormones and antibodies were measured in serum.

Results: Median UIC, BMIC and iodine intake across both areas was 350 μg/L, 479 μg/L and 407 μg/day, respectively. In multiple regression analyses, we discovered that being from VHI area was associated with higher UIC and BMIC. BMIC was also positively associated with iodine intake. Thyroid dysfunction and/or positive thyroid antibodies were found in 33.3% of the women, of which 18.9% had hypothyroidism and 8.1% had hyperthyroidism and 6.3% had positive antibodies with normal thyroid function. Elevated thyroid antibodies were in total found in 17.1%. We found no difference in distribution of thyroid dysfunction or positive antibodies between HI and VHI areas. BMI, BMIC and elevated thyroglobulin (Tg) predicted abnormal thyroid function tests.

Conclusions: The high prevalence of thyroid dysfunction may be caused by excessive iodine intake over several years.
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http://dx.doi.org/10.1016/j.jtemb.2014.09.009DOI Listing
February 2016
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