scholarly journals Iodine Status, Thyroid Function, and Birthweight: A Complex Relationship in High-Risk Pregnancies

2020 ◽  
Vol 9 (1) ◽  
pp. 177 ◽  
Author(s):  
Inés Velasco ◽  
Mar Sánchez-Gila ◽  
Sebastián Manzanares ◽  
Peter Taylor ◽  
Eduardo García-Fuentes
Keyword(s):  
High Risk ◽  
Amniotic Fluid ◽  
Cord Blood ◽  
Thyroid Function ◽  
Urinary Iodine ◽  
Iodine Concentration ◽  
Free Thyroxine ◽  
Urinary Iodine Concentration ◽  
Iodine Status ◽  
Iodine Metabolism

(1) Background: The consequences of iodine deficiency and/or thyroid dysfunction during pregnancy have been extensively studied, emphasizing on infant neurodevelopment. However, the available information about the relationship between iodine, thyroid hormones, and fetal growth in high-risk pregnancies is limited. We aim to investigate if iodine metabolism and/or thyroid parameters can be affected by adverse antenatal/perinatal conditions. (2) Methods: A cross-sectional study examined differences in iodine status, thyroid function, and birthweight between high-risk (HR group; n = 108)) and low-risk pregnancies (LR group; n = 233) at the time of birth. Urinary iodine concentration (UIC), iodine levels in amniotic fluid, and thyroid parameters [thyroid-stimulating hormone (TSH), free thyroxine (FT4)] were measured in mother–baby pairs. (3) Results: There were significant differences between HR and LR groups, free thyroxine (FT4) concentration in cord blood was significantly higher in the LR group compared with HR pregnancies (17.06 pmol/L vs. 15.30 pmol/L, respectively; p < 0.001), meanwhile iodine concentration in amniotic fluid was significantly lower (13.11 µg/L vs. 19.65 µg/L, respectively; p < 0.001). (4) Conclusions: Our findings support the hypothesis that an adverse intrauterine environment can compromise the availability of FT4 in cord blood as well as the iodine metabolism in the fetus. These differences are more noticeable in preterm and/or small fetuses.

Saliva Iodine Concentration in Children and Its Association with Iodine Status and Thyroid Function

2020 ◽  
Vol 105 (9) ◽  
pp. e3451-e3459 ◽  
Author(s):  
Wenxing Guo ◽  
Ziyun Pan ◽  
Ying Zhang ◽  
Ya Jin ◽  
Shuyao Dong ◽  
...  
Keyword(s):  
Thyroid Function ◽  
Primary Schools ◽  
Urinary Iodine ◽  
Reference Value ◽  
Iodine Concentration ◽  
Cross Sectional Study ◽  
Urinary Iodine Excretion ◽  
Urinary Iodine Concentration ◽  
Cross Sectional ◽  
Iodine Status

Abstract Context The effectiveness of saliva iodine concentration (SIC) in evaluating iodine status in children is not clear. Objective We aimed to explore associations between SIC and assessed indicators of iodine status and thyroid function. Design Cross-sectional study. Setting Primary schools in Shandong, China. Participants Local children aged 8 to 13 years with no known thyroid disease were recruited to this study. Main outcome measures Blood, saliva, and urine samples were collected to evaluate thyroid function and iodine status. Results SIC positively correlated with spot urinary iodine concentration (r = 0.29, P &lt; 0.0001), 24-hour urinary iodine concentration (r = 0.35, P &lt; 0.0001), and 24-hour urinary iodine excretion (r = 0.40, P &lt; 0.0001). The prevalence of thyroid nodules (TN) and goiter showed an upward trend with SIC quantiles (P for trend &lt; 0.05). Children with SIC &lt;105 μg/L had a higher risk of insufficient iodine status (OR = 4.18; 95% CI, 2.67-6.56) compared with those with higher SIC. Those having SIC &gt;273 μg/L were associated with greater risks of TN (OR = 2.70; 95% CI, 1.38-5.26) and excessive iodine status (OR = 18.56; 95% CI, 5.66-60.91) than those with lower SIC values. Conclusions There is a good correlation between SIC and urinary iodine concentrations. It is of significant reference value for the diagnosis of iodine deficiency with SIC of less than 105 μg/L and for the diagnosis of iodine excess and TN with SIC of more than 273 μg/L. Given the sanitary nature and convenience of saliva iodine collection, SIC is highly recommended as a good biomarker of recent iodine status in school-aged children.

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

Nutrients ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3483
Author(s):  
Inger Aakre ◽  
Lidunn Tveito Evensen ◽  
Marian Kjellevold ◽  
Lisbeth Dahl ◽  
Sigrun Henjum ◽  
...  
Keyword(s):  
Thyroid Function ◽  
Urinary Iodine ◽  
Iodine Content ◽  
Iodine Concentration ◽  
Iodine Intake ◽  
Thyroid Stimulating Hormone ◽  
Urinary Iodine Concentration ◽  
Free Triiodothyronine ◽  
Iodine Status ◽  
Excessive Iodine

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 (n = 44) to measure urinary iodine concentration (UIC) after habitual consumption of seaweed. Serum thyroid stimulating hormone (TSH), free thyroxine (fT4), free triiodothyronine (fT3), and peroxidase autoantibody (TPOAb), were measured in a subgroup (n = 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.

scholarly journals Iodine Status of Taiwanese Population in 2013: 10 Years After Changing From Mandatory to Voluntary Salt Iodization

2017 ◽  
Vol 39 (1) ◽  
pp. 75-85 ◽  
Author(s):  
Fan-Fen Wang ◽  
Kam-Tsun Tang ◽  
Wen-Harn Pan ◽  
Justin Ging-Shing Won ◽  
Yao-Te Hsieh ◽  
...  
Keyword(s):  
Age Groups ◽  
Urinary Iodine ◽  
Iodine Concentration ◽  
World Health ◽  
Urinary Iodine Concentration ◽  
Taiwanese Population ◽  
Iodine Nutrition ◽  
Iodine Status ◽  
Salt Iodization ◽  
Health Organization

Background: In 2003, Taiwan’s iodine policy changed from mandatory to voluntary. The Nutrition and Health Survey in Taiwan (NAHSIT) 2001-2002 for schoolchildren showed adequate iodine nutrition, while NAHSIT 2005-2008 for adults showed the iodine status was at borderline adequacy. Objective: To investigate the iodine status of the Taiwanese population from schoolchildren to adulthood 10 years after the change of the salt iodization policy. Method: Urinary iodine was measured in samples from subjects in NAHSIT 2013. Results: The median urinary iodine concentration (UIC) of the Taiwanese population aged 6 years and above in 2013 was 96 μg/L, indicating mild iodine deficiency. The median UIC of 6- to 12-year-old schoolchildren was 124 μg/L (interquartile range [IQR]: 92-213 μg/L), and 115 μg/L (IQR: 80-166 μg/L), 125 μg/L (IQR: 74-161 μg/L), 73 μg/L (IQR: 52-131 μg/L), and 78 μg/L (IQR: 52-132 μg/L) in populations aged 13 to 18 years, 19 to 44 years, 45 to 64 years, and ≥65 years, respectively. Declining iodine nutrition in age groups ≥45 years old was noted that the median UIC of populations aged 45 to 64 years and ≥65 years was 99 and 88 μg/L, respectively, in NAHSIT 2005-2008. The median UIC of schoolchildren was not lower than that during the mandatory salt fortification period, but the distribution of urinary iodine levels signified a dietary pattern change. Conclusion: Wide-ranging variation in iodine nutrition levels was observed in different age groups. Universal salt iodization, as suggested by the World Health Organization, should be the best strategy to achieve adequate iodine nutrition.

scholarly journals Iodine status of consumers of milk-alternative drinks v. cows’ milk: data from the UK National Diet and Nutrition Survey

2020 ◽  
pp. 1-9
Author(s):  
M. Dineva ◽  
M. P. Rayman ◽  
S. C. Bath
Keyword(s):  
At Risk ◽  
Iodine Deficiency ◽  
Urinary Iodine ◽  
Iodine Concentration ◽  
Iodine Intake ◽  
Urinary Iodine Concentration ◽  
Nutrition Survey ◽  
Iodine Status ◽  
Adults And Children ◽  
The Uk

Abstract Milk is the main source of iodine in the UK; however, the consumption and popularity of plant-based milk-alternative drinks are increasing. Consumers may be at risk of iodine deficiency as, unless fortified, milk alternatives have a low iodine concentration. We therefore aimed to compare the iodine intake and status of milk-alternative consumers with that of cows’ milk consumers. We used data from the UK National Diet and Nutrition Survey from years 7 to 9 (2014–2017; before a few manufacturers fortified their milk-alternative drinks with iodine). Data from 4-d food diaries were used to identify consumers of milk-alternative drinks and cows’ milk, along with the estimation of their iodine intake (µg/d) (available for n 3976 adults and children ≥1·5 years). Iodine status was based on urinary iodine concentration (UIC, µg/l) from spot-urine samples (available for n 2845 adults and children ≥4 years). Milk-alternative drinks were consumed by 4·6 % (n 185; n 88 consumed these drinks exclusively). Iodine intake was significantly lower in exclusive consumers of milk alternatives than cows’ milk consumers (94 v. 129 µg/d; P < 0·001). Exclusive consumers of milk alternatives also had a lower median UIC than cows’ milk consumers (79 v. 132 µg/l; P < 0·001) and were classified as iodine deficient by the WHO criterion (median UIC < 100 µg/l), whereas cows’ milk consumers were iodine sufficient. These data show that consumers of unfortified milk-alternative drinks are at risk of iodine deficiency. As a greater number of people consume milk-alternative drinks, it is important that these products are fortified appropriately to provide a similar iodine content to that of cows’ milk.

scholarly journals Variation of iodine status during pregnancy and its associations with thyroid function in women from Rio de Janeiro, Brazil

2019 ◽  
pp. 1-9 ◽  
Author(s):  
Carolina Martins Corcino ◽  
Tatiana Martins Benvenuto Louro Berbara ◽  
Débora Ayres Saraiva ◽  
Nathalie Anne de Oliveira e Silva de Morais ◽  
Annie Schtscherbyna ◽  
...  
Keyword(s):  
Thyroid Function ◽  
Subclinical Hypothyroidism ◽  
Rio De Janeiro ◽  
Urinary Iodine ◽  
Urinary Iodine Concentration ◽  
Thyroid Antibodies ◽  
Third Trimester ◽  
Iodine Status ◽  
The Third ◽  
Increased Risk

AbstractObjectiveTo assess iodine status and its effects on maternal thyroid function throughout pregnancy.DesignIn the present prospective cohort study, three urinary samples were requested for urinary iodine concentration (UIC) determinations in both the first and third gestational trimesters. Serum thyrotropin (TSH) and free thyroxine (FT4) were analysed in both trimesters and thyroid antibodies were assessed once.SettingRio de Janeiro, Brazil.ParticipantsFirst-trimester pregnant women (n243), of whom 100 were re-evaluated during the third trimester.ResultsIodine sufficiency was found in the studied population (median UIC=216·7 µg/l). The first- and third-trimester median UIC was 221·0 and 208·0 µg/l, respectively. TSH levels (mean (sd)) were higher in the third trimester (1·08 (0·67)v. 1·67 (0·86) mIU/l;P<0·001), while FT4levels decreased significantly (1·18 (0·16)v. 0·88 (0·12) ng/dl;P<0·001), regardless the presence of iodine deficiency (UIC<150 µg/l) or circulating thyroid antibodies. UIC correlated (β; 95% CI) independently and negatively with age (–0·43; –0·71, –0·17) and positively with multiparity (0·15; 0·02, 0·28) and BMI (0·25; 0·00, 0·50). Furthermore, median UIC per pregnant woman tended to correlate positively with TSH (0·07; –0·01, 0·14). Women with median UIC≥250 µg/l and at least one sample ≥500 µg/l throughout pregnancy had a higher risk of subclinical hypothyroidism (OR=6·6; 95% CI 1·2, 37·4).ConclusionsIn this cohort with adequate iodine status during pregnancy, excessive UIC was associated with an increased risk of subclinical hypothyroidism.

scholarly journals Two Sources of Maternal Iodine Intake and Their Effect on Maternal and Infant Iodine Status and Thyroid Function and Infant Information Processing in Southern Ethiopia (P11-007-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Tafere Gebreegziabher ◽  
Barbara Stoecker
Keyword(s):  
Information Processing ◽  
Thyroid Function ◽  
Visual Information ◽  
Urinary Iodine ◽  
Iodine Concentration ◽  
Thyroid Stimulating Hormone ◽  
Iodized Salt ◽  
Southern Ethiopia ◽  
Urinary Iodine Concentration ◽  
Iodine Supplementation

Abstract Objectives The objective of this study was to assess the effects of two sources of iodine supplementation on maternal and infant thyroid function and on visual information processing (VIP) of infants in southern Ethiopia Methods A community-based, randomized, supplementation trial was conducted. Mother infant dyads (n = 106) were recruited within the first week after delivery to participate in this study. Mothers were randomly assigned either to receive a potassium iodide capsule (225 µg iodine) daily for 26 weeks or appropriately iodized salt weekly for 26 weeks for household consumption. Maternal thyroxine (T4), triiodothyronine (T3), thyroid stimulating hormone (TSH), thyroglobulin (Tg), urinary iodine concentration (UIC), breast milk iodine concentration (BMIC) and infant T4, TSH, UIC and VIP were measured as outcome variables. Results At baseline, neither mothers nor infants in the two groups (capsule and iodized salt groups) were significantly different in any of the biomarkers and anthropometry measurements. Maternal TSH and goiter rate significantly decreased following iodine supplementation but T3, T4 and Tg didn't change. Maternal UIC and BMIC and infant UIC were not different among groups. Conclusions A maternal dose of 225 µg iodine daily or adequately iodized salt initiated within a week after delivery decreased goiter and TSH but did not impact infant T4, TSH or VIP. The two treatment groups didn't differ in any of the outcome variables. Funding Sources The study was funded by Nestlé Foundation and Oklahoma State University.

scholarly journals Changing Dietary Habits in Veneto Region over Two Decades: Still a Long Road to Go to Reach an Iodine-Sufficient Status

Nutrients ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2399 ◽  
Author(s):  
Simona Censi ◽  
Jacopo Manso ◽  
Susi Barollo ◽  
Alberto Mondin ◽  
Loris Bertazza ◽  
...  
Keyword(s):  
Dietary Habits ◽  
Urinary Iodine ◽  
Iodine Concentration ◽  
Iodine Intake ◽  
Iodized Salt ◽  
Urinary Iodine Concentration ◽  
Milk Product ◽  
Veneto Region ◽  
School Students ◽  
Iodine Status

Background: Fifteen years after a nationwide voluntary iodine prophylaxis program was introduced, the aims of the present study were: (a) to obtain an up-to-date assessment of dietary iodine intake in the Veneto region, Italy; and (b) to assess dietary and socioeconomic factors that might influence iodine status. Methods: Urinary iodine concentration (UIC) was obtained in 747 school students (median age 13 years; range: 11–16 years). Results: The median UIC was 111 μg/L, with 56% of samples ≥ 100 μg/L, but 26% were < 50 μg/L, more frequently females. Iodized salt was used by 82% of the students. The median UIC was higher among users of iodized salt than among non-users, 117.0 ug/L versus 90 ug/L (p = 0.01). The median UIC was higher in regular consumers of cow’s milk than in occasional consumers, 132.0 μg/L versus 96.0 μg/L (p < 0.01). A regular intake of milk and/or the use of iodized salt sufficed to reach an adequate median UIC, although satisfying only with the combined use. A trend towards higher UIC values emerged in regular consumers of cheese and yogurt. Conclusion: Iodine status has improved (median UIC 111.0 μg/L), but it is still not adequate as 26% had a UIC < 50 μg/L in the resident population of the Veneto region. A more widespread use of iodized salt but also milk and milk product consumption may have been one of the key factors in achieving this partial improvement.

scholarly journals Urinary iodine concentration: a biochemical parameter for assessing the iodine status

Mediscope ◽  
2018 ◽  
Vol 5 (2) ◽  
pp. 30-35
Author(s):  
GM Molla
Keyword(s):  
Iodine Deficiency ◽  
Urinary Iodine ◽  
Iodine Concentration ◽  
Iodine Intake ◽  
Urinary Iodine Concentration ◽  
Lactating Women ◽  
Iodine Status ◽  
Excessive Iodine ◽  
Pregnancy And Lactation ◽  
Neonates And Infants

Iodine is a micronutrient, which is essential for the synthesis of thyroid hormones. Thyroid hormones play a major role in the development of different functional components in different stages of life. The relationship between iodine intake level of a population and occurrences of thyroid disorders U-shaped with an increase from both low and high iodine intake. Iodine deficiency disorders (IDDs) are a major health problem worldwide in all age groups, but infants, school children, and pregnant and lactating women are vulnerable. During pregnancy and lactation, the fetus and infants are sensitive to maternal iodine intake. Even mild iodine deficiency may lead to irreversible brain damage during this period. A main cause of IDDs of neonates and infants is maternal iodine deficiency. Universal salt iodization strategy has been initiated by the World Health Organization and United Nation International Children Emergency Fund by the year 1993 for correction and prevention of iodine deficiency. Excessive iodine causes hypothyroidism, iodine-induced hyperthyroidism and autoimmune thyroid diseases. Iodine deficiency and excessive iodine, both cause goiter. There are many indicators for assessing the IDDs, such as measurement of thyroid size by palpation or ultrasonography, serum thyroid stimulating hormone, and thyroglobulin but these are less sensitive, costly and sometimes interpretation is difficult. Urinary iodine concentration (UIC) is a well-accepted, cost-efficient, and easily obtainable indicator of iodine status. Since the majority of iodine absorbed by the body is excreted in the urine, it is considered a sensitive marker of current iodine intake and can reflect recent changes in iodine status. Iodine requirements are greatly increased during pregnancy and lactation, owing to metabolic changes. During intrauterine life, maternal iodine is the only source of iodine for a fetus. UIC determines the iodine status of pregnant and lactating women. Breast milk is the only source of iodine for exclusively breastfed neonates and infants. Breast milk iodine concentration can be determined by UIC. UIC predicts the adverse health consequences of excessive iodine intake such as goiter, hypothyroidism, and hyperthyroidism. This review presents that iodine status in different groups of a population can be determined by UIC which will be helpful in assessing the iodine status in a community, finding out the cause of thyroid disorders, to predict the risk of adverse health effects of iodine deficiency and excessive iodine, and in making plan for iodine supplementation.Mediscope Vol. 5, No. 2: Jul 2018, Page 30-35

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