Median Urinary Iodine Concentration Research Articles

Micronutrient intake and nutritional status in 16-to-24-year-olds adhering to vegan, lacto-ovo-vegetarian, pescatarian or omnivorous diets in Sweden

PurposeThe nutritional adequacy of plant-based diets for youth is of public health relevance but is insufficiently studied. This cross-sectional study aims to assess the micronutrient intake and nutritional status in youth adhering to vegan, lacto-ovo-vegetarian, pescatarian or omnivorous diets in Sweden.MethodsHealthy 16-to-24-year-olds (n = 60 vegans, n = 59 lacto-ovo-vegetarians, n = 55 pescatarians, n = 61 omnivores) completed a 255-item web-based questionnaire, conducted four non-consecutive 24-hour dietary recalls, provided capillary blood samples and one spot urine sample. Usual micronutrient intakes were estimated by the Multiple Source Method. At the group level, risk of inadequate intake was defined as > 50% with intakes below average requirements. Samples were analysed for haemoglobin (HB), serum transferrin receptor (sTfR), homocysteine (tHcy), methylmalonic acid (MMA), 25-hydroxyvitamin D3 (25-OH-D3), and urinary iodine concentration (UIC).ResultsFrom foods and supplements, all dietary groups demonstrated a risk of inadequate intakes of vitamin D and selenium, additionally vitamin A and calcium in vegans, B12 in lacto-ovo-vegetarians, and potassium in pescatarians. Median blood marker values of HB, sTfR, tHcy and MMA were within normal ranges across dietary groups. Insufficient 25-OH-D3 concentration (< 50 nmol/L) was observed in vegans, lacto-ovo-vegetarians, and omnivores. A significantly higher proportion of vegans were at risk of vitamin D deficiency (25-OH-D3 < 30 nmol/L) than pescatarians and omnivores. Median UIC (< 100 µg/L) indicated a risk of inadequate iodine intake in vegans, pescatarians, and omnivores.ConclusionYouth, regardless of dietary practice, need support to ensure adequate micronutrient intakes, particularly for vitamin D and selenium. Further research is required to evaluate iodine nutrition in Swedish youth.

Iodine and selenium intakes and status and thyroid function in midlife women with low bread intakes in New Zealand.

Iodine and selenium are important nutrients for thyroid function; however, the New Zealand food supply is generally low in both minerals. Bread can be a good source of these minerals; although the popularity of lower carbohydrate diets means some people avoid bread. This study aimed to investigate the effect of low bread intakes on iodine and selenium intakes and status, and thyroid function in mid-life women in New Zealand. Self-selecting women (n = 46), aged 40-63 years, with a mean daily intake of 1.6 ± 1.5 slices of fortified commercial bread, were recruited into a cross-sectional study in Auckland, New Zealand. Assessment of iodine and selenium intake was via a 3-day diet diary. Iodine and selenium concentrations were measured in 24-h urine samples and selenium concentrations in plasma using inductively coupled plasma mass spectrometry. Thyroid hormones including triiodothyronine and thyroxine were also determined. Median urinary iodine concentration was 49 (35, 78; 25, 75 centile) μg/L indicating iodine deficiency. Of plasma samples measured, 32% had selenium concentrations below 110 μg/L, suggesting inadequacy. Data suggested at least 40% of participants had low intakes of both nutrients. Only two participants had impaired thyroid function; however, plasma selenium concentrations predicted the ratio of triiodothyronine to thyroxine (p = 0.038). A high prevalence of inadequate selenium and iodine intake was observed in women with low bread intakes. Those with low bread intakes need to ensure they consume alternative sources such as dairy, fish and seafood, eggs, meat, other grains, and nuts.

Iodine intake and status of school-age girls in Ireland

PurposeInsufficient iodine intake can lead to a variety of preventable health and developmental outcomes. Consequently, continuous monitoring of a population’s iodine adequacy is important. The aim of this study was to examine iodine intake and status in a nationally representative sample of school-age girls living in Ireland.MethodsAnalyses were based on 516 schoolgirls aged 5–18 years from the cross-sectional National Children’s Food Survey II (2017–2018) and the National Teens’ Food Survey II (2019–2020). Dietary data were collected using a four-day weighed food diary. Adequacy of iodine intake and the contribution of food categories to overall dietary iodine intake was assessed. Urinary iodine concentration (UIC) was measured using a spot urine sample using the Sandell-Kolthoff reaction by a modified microplate method.ResultsMedian iodine intake was 94.8 µg/d (IQR 54.9–155.5 µg/d), with 40% of girls having intakes below the estimated average requirement (EAR). The median UIC was 87.8 µg/L, with younger girls having a significantly higher UIC compared to older girls (104.4 µg/L − 77.0 µg/L respectively; p < 0.001). The main dietary source was milk, contributing to over 50% of iodine intake, with non-consumers of milk having significantly lower dietary and urinary iodine levels compared to high consumers (p < 0.001).ConclusionThis study suggests that school aged girls living in Ireland have mild iodine deficiency and given the concerns associated with such deficiencies and their potential public health implications, it is essential that iodine status in other population groups in Ireland is ascertained. The need for targeted public health strategies to eradicate iodine deficiency may be warranted.

Association of maternal urinary pesticide metabolites with neonatal birth outcomes and the moderating effects of iodine.

Association of maternal urinary pesticide metabolites with neonatal birth outcomes and the moderating effects of iodine.

Factors influencing thyroid volume and comparative analysis of thyroid volume correction methods in children aged 8-10 years in Gansu, China.

This study aimed to analyze the relationship between thyroid volume (TVOL) and physical development of children, and explore the suitable TVOL correction methods. 1500 children aged 8-10 years from Gansu province northwest China were selected. The height (H), weight (W), urine iodine of children was measured and their thyroid was examined by ultrasound. Body mass index (BMI), body surface area (BSA) and TVOL were calculated (BSA calculated by three formulas). The relationship between TVOL and age, sex, physical development was analyzed. The applicability of TVOL correction methods including BMI corrected volume (BMIV), BSA corrected volume (BSAV), weight and height corrected volume indicator (WHVI) and height corrected volume indicator (HVI) were compared. Median urinary iodine concentrations of children aged 8, 9, 10 years were 166.6 μg/L, 167.2 μg/L and 178.8 μg/L respectively. The rate of iodine deficiency was 20.3%, the rate of thyroid goiter was 3.2%. Physical development indexes (height, weight, BMI and BSA) and TVOL increased with age. Also, physical development indexes (height, weight, BMI and BSA) of boys were higher than girls (p <0.05). Only BSAV1 had no correlation with all physical development indexes (p >0.05). The TVOL P97 (97th percentile) of children aged 8, 9, 10 years were 4.4 ml, 4.9 ml, 6.5 ml, the values were 4.6 mL, 4.7 mL, 5.9 mL after BSAV1 corrected. The difference between TVOL and BSAV1 ranges from -0.37% to 0.36%. The thyroid volume is not only affected by age, but it is also affected by physical development. Thyroid goiter should be assessed based on age and physical development. The formula BSAV1=TVOL/ (W0.425×H0.725×71.84×10-4) was a suitable TVOL correction method.

The myth of iodine: A systematic review and meta-analysis on the relationship between iodine and thyroid nodule.

Iodine is an essential trace element for thyroid hormone synthesis, and its role in thyroid health has been widely studied. While iodine deficiency is recognized as a risk factor for goiter, its association with thyroid nodules remains controversial. The aim of this systematic review and meta-analysis was to evaluate the relationship between iodine intake and the development of thyroid nodules. A systematic literature search was conducted in Medline (via PubMed), the Cochrane Library, and guideline registries (AWMF, GIN) for studies published between 2012 and 2023. Inclusion criteria focused on studies examining the association between iodine intake and thyroid nodule. Systematic review has been conducted whereas study quality was assessed using the checklists of Critical Appraisal Skills Programme (CASP). A meta-analysis was performed for studies reporting odds ratios based on WHO-defined iodine categories. A total of 31 studies were included. Most studies (n = 23) were cross-sectional, limiting causal conclusions. The most used method for assessing iodine intake was urinary iodine concentration (UIC), though measurement approaches varied. N = 10 studies compared median UIC between groups with and without thyroid nodules, with n = 8 reporting significant differences. However, the iodine levels in both groups often remained within the WHO-defined adequate iodine range. N = 8 studies examined odds ratios for iodine intake and thyroid nodule risk, with n = 5 identifying iodine deficiency (< 100 μg/L) as a significant risk factor. However, results for more than adequate (> 200 μg/L) and excessive iodine intake (> 300 μg/L) were inconsistent. N = 3 studies suggested a U-shaped relationship between iodine and thyroid nodule prevalence, but meta-analysis findings did not confirm this hypothesis. The pooled odds ratio for iodine deficiency was 1.24 (95% CI [1.16-1.33], I2 = 0.00), while more than adequate and excessive iodine intake showed no significant association. This systematic review and meta-analysis indicate that iodine deficiency increases moderately the risk of developing thyroid nodules, while more than adequate and excessive iodine intake does not show a consistent effect. However, the heterogeneity of study results and the predominance of cross-sectional designs limit definitive conclusions. Further prospective studies are needed to clarify the causal relationship between iodine intake and thyroid nodules.

Household iodized salt consumption and iodine status in women of reproductive age in Angola: a cross-sectional study

BackgroundThe first evaluation of iodine nutritional status in Angola was carried out in 2006. This involved a limited survey of urinary iodine concentration (UIC) among school-aged children, conducted in 24 schools within the municipalities of Bié Province. Almost all the children had moderate to high levels of iodine deficiency, with a median UIC below 100 μg/L. In 2004, the Iodine Global Network ranked Angola among the world's ten countries with the highest prevalence of iodine deficiency. This study aims to assess the household level of iodized salt and iodine status in women of reproductive age in Angola.MethodsIn 2019, we conducted an observational, descriptive, prospective, cross-sectional study, stratified by altitude, using data from the 2014 Census. A multi-stage, proportional stratified sample selected 2250 households across the country, with 450 per province (Luanda, Cuanza Sul, Bie, Cunene, and Moxico). Descriptive statistics (means, medians, frequencies) were used to characterize the variables. Chi-squared and Kruskal–Wallis tests were employed to assess differences in iodine concentration between strata.ResultsOverall, the findings indicated that 74.3% of households used salt containing some iodine, but only 29.2% used salt with adequate iodization (15–40 ppm). The median UIC was 102.2 µg/L in pregnant women and 108.2 µg/L in non-pregnant women. No statistically significant difference was observed between these two groups (p = 0.48).ConclusionsKey findings of the survey showed that the majority of the population in this study is consuming iodized salt below the range recommended by the World Health Organization. This result highlights the need to review the current iodine deficiency disorder control program and develop a country action plan to ensure that over 90 percent of households sustainably use adequately iodized salt and all women of reproductive age have adequate iodine intake.

Iodine intakes of pregnant females from Québec, Canada.

Iodine intakes of pregnant females from Québec, Canada.

Senegal’s Iodine Puzzle: Iodine Status, Salt Iodization, and Dietary Iodine Sources

Senegal’s Iodine Puzzle: Iodine Status, Salt Iodization, and Dietary Iodine Sources

Iodine nutritional status in different trimesters of pregnancy and its association with dietary habits: a prospective observational study in Taiwan

BackgroundPregnant women are susceptible to iodine deficiency. Most iodine nutritional studies in pregnant women have involved cross-sectional evaluations of iodine status. This prospective observational study was designed to longitudinally follow the iodine status of pregnant women in different trimesters of pregnancy and to assess the demographic characteristics and dietary influences on iodine status.MethodsA prospective cohort study was conducted at Taipei Veterans General Hospital from March 2019 to July 2022. A total of 211 women were enrolled and each subject was asked to provide a spot urine sample at each trimester. Urinary iodine concentration (UIC) was measured using inductively coupled plasma-mass spectrometry. Dietary habit was assessed via food frequency questionnaires (FFQs) at each trimester.ResultsThe median UICs for the first, second and third trimesters were 156.3 µg/L (interquartile range [IQR]: 100.7-241.1), 146.2 µg/L (84.6-224.4), and 169.9 µg/L (94.4-283.5), respectively. Compared to the first trimester, participants consumed seaweed (p = 0.004 and p < 0.001, respectively), fish (p < 0.001 for both), and prenatal multivitamins (p < 0.001 for both) more frequently during the second and third trimesters. Additionally, an increasing number of women raised their intake of dairy products as their pregnancies progressed. Multivariate analysis indicated a positive association between nulliparity and UIC < 150 µg/L (adjusted odds ratio [OR]: 2.258, 95% confidence interval [CI]: 1.167–4.367, p = 0.02). Additionally, less prenatal iodine-containing multivitamin intake increased the odds of UIC < 150 µg/L across all trimesters (adjusted OR: 2.562, 95% CI: 1.234–5.319; p = 0.01 for the first trimester; adjusted OR: 2.264, 95% CI: 1.167–4.395; p = 0.02 for the second trimester; and adjusted OR: 2.022, 95% CI: 1.031–3.967; p = 0.04 for the third trimester).ConclusionsMild iodine deficiency was observed in the second trimester despite adequate iodine status in the first and third trimesters. Nulliparous women and those not ingesting iodine-containing multivitamins are at greater risk of iodine deficiency, highlighting the need for targeted dietary education and interventions.

Resurgence of Iodine Deficiency in the United States During Pregnancy: Potential Implications for Cognitive Development in Children

Abstract Iodine is an essential trace mineral for thyroid hormone synthesis, metabolism, and neurological development, particularly during pregnancy and early childhood. Although salt iodization in the 1920s significantly reduced iodine deficiency, recent studies suggest a resurgence in the United States, particularly among pregnant women. This review examines the resurgence of iodine deficiency among women in the United States while highlighting factors influencing intake, focusing on maternal iodine status during pregnancy, followed by its implications on cognitive health of children globally. Articles published from 2010 to 2024 were identified using PubMed, EMBASE, and Cochrane databases following PRISMA 2020 guidelines. Search terms included “iodine deficiency in women” and “maternal iodine deficiency and neurodevelopment.” Studies on urinary iodine concentration (UIC) in nonpregnant, pregnant, and lactating women in the United States, and maternal iodine deficiency impact on offspring neurodevelopment globally, were included. Nine articles were reviewed addressing current iodine status among women in the United States, 4 of which used the National Health and Nutrition Examination Survey (NHANES). NHANES data (2011–2020) indicated declining median UIC (mUIC) among women of reproductive age and mUICs in pregnant women were below the World Health Organization recommendation (&amp;lt;150 µg/L). Prevalence of inadequate iodine status ranged from 23% to 59% in pregnant women. The primary contributing factor to declining iodine status is dietary changes, specifically reduced milk consumption. Eleven additional articles examined maternal UIC and cognition in global populations, highlighting the association between low UIC during pregnancy, particularly in the first and second trimesters, and poor neurodevelopmental outcomes such as reduced IQ scores in offspring outside of the United States. Offspring born to mothers with iodine deficiency are at greater risk of poor cognitive health. Comprehensive nutrition policies are needed to raise awareness of adequate iodine intake during critical developmental periods and to support food-system changes, ensuring sufficient intake.

Does the island area also need to insist on salt iodization to prevent iodine deficiency disorders? a cross-sectional survey in Hainan Province, China.

To investigate the epidemiology and related factors of iodine deficiency disorders (IDD) in Hainan Province, to know the iodine nutrition status and thyroid disease status of residents, and to explore whether salt iodization should be adopted to prevent and control IDD in island areas. To provide a basis for the effective implementation of scientific iodine supplement prevention and control strategy. All 21 cities, counties (districts) in the province were investigated. Superficial soil, residential drinking water, common food, urine samples of children, adults and pregnant women, household salt samples, thyroid B-ultrasound of adults and pregnant women, adult blood samples were collected. Soil iodine, water iodine, food iodine, urine iodine, daily salt intake, salt iodine, thyroid volume, nodules and thyroid function were measured. The median iodine content in soil was 4.37mg/kg, the median iodine content in drinking water was 6.0μg/L, the iodized salt coverage rate was 98.6%, and the consumption rate of qualified iodized salt was 97.9%. The median urinary iodine concentration (MUIC) in children and adults was 180.3μg/L and 151.6μg/L, respectively, which was the adequate level of iodine. The median urinary iodine in pregnant women was 144.6μg/L, which was slightly lower than the adequate level. The main source of iodine intake was salt iodine, which contributed 59.8% to total dietary iodine. Kelp, milk and seaweed, whose contribution rates were 8.2%, 7.3% and 6.6%, respectively. The total iodine contribution rate of other foods was 18.1%, among which the contribution rate of fish, shrimp and crabs was only 2.4%. The overall prevalence of thyroid diseases was 27.01%. The detection rates of subclinical hypothyroidism and subclinical hyperthyroidism in males were significantly higher than those in females, and the detection rates of thyroid nodules and goiter were significantly lower than those in females. The detection rates of thyroid nodules in central mountainous areas were significantly higher than those in eastern and western coastal areas. At present, the iodine nutrition level in Hainan Province is generally in a suitable state, and the iodine intake of residents mainly comes from iodized salt. The strategy of salt iodization prevention and control of IDD should be adhered to in island area.

A Cross-Sectional Study of Iodine Nutritional Status Among School-Age Children in Chongqing, China.

Objectives: The aim of the present study was to evaluate the iodine nutritional statuses of children aged 8 to 10 years in Chongqing Municipality in 2023. Methods: In this study, we employed multi-stage stratified cluster sampling of non-boarding children aged 8 to 10 years in all 39 counties (districts). The levels of iodine in household salt and those in random urine samples collected from the subjects were tested. In addition, thyroid gland volume was examined using the ultrasound method in subjects from 13 of the counties (districts). Results: Of the total 7751 children aged 8 to 10 years selected for inclusion in this study, the median salt iodine concentration (SIC) was 26.7 mg/kg, with an interquartile range (IQR) of 24.2-29.4 mg/kg. The median urinary iodine concentration (UIC) was 226.4 μg/L, with an IQR of 149.5-309.6 μg/L. The median UIC differed significantly between genders and across various regions (p < 0.001). The prevalence of total goiter in the children was 2.24% (58/2591), and significant differences were observed in the prevalence of goiter in different body mass index (BMI) groups (p < 0.001). The greatest prevalence of goiter was observed in obese children. Conclusions: In 2023, children in Chongqing Municipality aged 8 to 10 years as a whole had adequate iodine nutrition and met the national standard for the eradication of iodine deficiency disorders.

Impact of Thyroid Autoimmunity on Pregnancy in Iodine-Sufficient Areas

Abstract Objectives: Pregnancy has a profound impact on maternal thyroid morpho-functionality; thus, thyroid dysfunction can cause multiple perinatal risks and complications. The aim of the study is to determine the incidence of maternal thyroid autoimmunity and dysfunction, their influence on some gestational and perinatal parameters of the newborn, and the impact of iodine status on thyroid autoimmunity in a region with sufficient iodine intake. Material and method: Retrospective study conducted on a number of 74 full-term pregnancies with singletons, pregnant women originating from the perimarine area of Romania. The participants were divided into 2 groups: group 1 - pregnant with chronic autoimmune thyroiditis and subclinical/clinical manifest hypothyroidism; group 2 - pregnant without thyroid pathology considered as a control group. Maternal variables studied: dosage of thyroid hormone and antithyroid autoantibodies, median urinary iodine concentration; and for the newborns: birth weight, APGAR score, gestational age, incidence of perinatal events. The administration of iodine supplements during pregnancy was monitored. Results: The incidence of chronic autoimmune thyroiditis was 36.4%. Maternal thyroid autoimmunity is associated with low birth weight and premature birth compared to the control group. The predominant perinatal pathology among pregnant women with thyroid autoimmunity was represented by spontaneous abortion, presenting a 2.8x higher risk compared to the control group. Median urinary iodine concentration was under 150 mcg/L in both studied groups of pregnant women. Iodine nutritional deficiency, but also excess iodine intake, were positively correlated with maternal thyroid autoimmunity. Consumption of iodine supplements and iodized salt was reduced in the category of pregnant women with thyroid autoimmunity. Conclusions: Thyroid autoimmunity during pregnancy presents significant challenges even in iodine-sufficient geographical areas. Maternal autoimmune thyroiditis represents a risk factor with effects on fetal development and repercussions in the perinatal period. Evaluation of thyroid function parameters before conception or in the first weeks of pregnancy is recommended as a diagnostic and prophylactic measure.

A sentinel survey in remote Western Thailand indicates that school-aged children and reproductive-aged women of the Indigenous Pwo Karen community are iodine sufficient

Indigenous peoples are often not routinely included in iodine programmes because of language barriers and remote access and may thus be at higher risk of iodine deficiency disorders, which could adversely impact their quality of life. We conducted this cross-sectional study in the remote Pwo Karen community of Thailand to determine the urinary iodine concentration of school-aged children and women of reproductive age and investigate the iodine content in household salt. We measured urinary iodine concentration in spot urine samples from healthy school-aged children and women of reproductive age, administered a questionnaire, estimated daily iodine intake and collected household salt samples to determine salt iodine concentration. The median urinary iodine concentration (range) of school-aged children (n 170) was 192 (136–263) µg/l, which was significantly higher than women of reproductive age (n 306) (147 (89–233) µg/l) (P < 0·001). The estimated daily iodine intake in school-aged children and women of reproductive age were 135 and 195 μg/d, respectively. The median (range) iodine concentration in rock and granulated salts consumed in the households were 2·32 (0·52–3·19) and 26·64 (20·86–31·01) ppm, respectively. Surprisingly, the use of iodised salt and the frequency of seafood consumption were NS predictors of urinary iodine concentration in these two groups. Our data suggest that school children and women of the Pwo Karen community have sufficient iodine intake, indicating the Thai salt iodisation programme is effectively reaching even this isolated Indigenous community. Sentinel surveys of remote vulnerable populations can be a useful tool in national iodine programmes to ensure that programme coverage is truly universal.

Clinico-Etiological Profile of Goitrous Children of a Coastal Area and the Association Between Urinary Iodine Concentration and Thyroid Autoimmunity

Background: Iodine deficiency is unlikely to be a main cause of goitre in a coastal area, with a predominant sea food eating population. At the same time, excess iodine may cause thyroid autoimmunity and hypothyroidism via the Wolff-Chaikoff effect. Measurement of Urinary Iodine Concentration (UIC) per day is an excellent substitute for assessing the iodine intake. The objectives of this study are to describe the clinico-etiological profile and to determine the correlation between Urinary Iodine Concentration and thyroid autoimmunity in goitrous children below 12 years of age attending a tertiary care institute in a coastal area. Materials &amp; Methods: It was a cross-sectional analytical study in a coastal tertiary care institute. Children attending the department of Pediatrics were screened for goitre. UIC and thyroid autoimmunity were ascertained using standard techniques. Results: Nearly 1/3rd of goitrous children had thyroid autoimmunity. The median Urinary Iodine Concentration (UIC) of the study area was 210 μ/L, which is above adequate level, as per WHO grading. Conclusion: Thyroid autoimmunity is an important cause for goiter in children from this coastal area and a high iodine intake may be contributing to this. Hence, the salt iodization in coastal areas may need a reconsideration. However, further community-based studies may help to provide an epidemiological level of recommendation regarding the iodine supplementation (salt iodization) in coastal areas.

The relationship between excessive iodine during pregnancy and adverse pregnancy complications.

Iodine nutrition during pregnancy plays an important role in fetal development and maternal outcomes. Iodine deficiency has been proved to be associated with maternal thyroid dysfunction, adverse fetal outcomes and neurodevelopmental disorders in offspring. At present, there are few studies concentrate on the effects of iodine excess during pregnancy on thyroid function, maternal and neonatal outcomes, and the results are still controversial. The aim of this study was to evaluate the effects of excessive iodine status on thyroid function, glycolipid metabolism, and maternal and neonatal outcomes. A total of 595 pregnant women who gave birth at the First Affiliated Hospital of Nanjing Medical University from January 2023 to December 2023 were included in this study. Blood and urine samples were collected during the second trimester of pregnancy. Thyroid function include thyroid-stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3) and urinary iodine concentrations (UIC) were measured. Maternal and neonatal outcomes were collected. Participants were divided into four groups based on UIC, with median UIC values of 100.5, 200, 314.2, and 655 μg/L, respectively. UIC was found to be positively associated with TSH, and negatively associated with FT3 and FT4. Fasting blood glucose (FBG) levels were elevated both in iodine deficiency and excess group. A U-shaped relationship between UIC and thyroid dysfunction were found. Iodine deficiency, excess iodine and even more than adequate iodine can lead to increased incidence of thyroid diseases such as isolated hypothyroxinaemia and overt hyperthyroidism. Importantly, iodine excess was found to be related with higher prevalence of umbilical cord around neck and eclampsia as well as higher blood glucose and low-density lipoprotein(LDL) level. Abnormal iodine status especially iodine excess during pregnancy was found to be related with higher prevalence of adverse mother and fetus outcomes, abnormal blood glucose and lipid level.

Micronutrient deficiencies and their co-occurrence among pregnant women in Mbeya region, Tanzania.

Micronutrient deficiencies, a global concern affecting vulnerable populations, including pregnant women, pose significant public health challenges. Specifically, micronutrient deficiencies in iron, vitamin A, iodine and folate have been of greatest public health concern among pregnant women. This study aimed to evaluate the co-occurrence of selected multiple micronutrient deficiencies among pregnant women attending Antenatal Care (ANC) in Mbeya, Tanzania. Employing a cross-sectional design, data were gathered from 420 pregnant women aged 15-49 years attending ANC in Mbeya Region. Semi-structured questionnaires captured socio-demographic data, and blood samples were collected for biomarkers assessment. The study used Stata 17.0 to analyze the data. Results revealed that six out of ten pregnant women exhibited at least one form of micronutrient deficiency, with 15.0% experiencing double deficiencies and 2.2% experiencing triple deficiencies. Iron Deficiency Anemia (IDA) was prevalent among 61.7% of anaemic pregnant women. Individual micronutrient deficiency rates were as follows: folate (21.7%), vitamin B12 (9.9%), iron (38.4%), vitamin A (9.8%), with a median Urinary Iodine Concentration (UIC) of 279.4μg/L. Pregnant women with anemia were more likely to have Multiple Micronutrient Deficiencies (MMD) compared to non-anemic counterparts (p-value <0.005). Additionally, those in the second trimester were at a higher risk of MMD than those in the first trimester (p-value <0.005). A higher wealth quantile appeared to protect against MMD (p-value <0.005). The study highlights the co-occurrence of MMD among pregnant women in Tanzania, indicates the necessity for an improved strategy to enhance multiple micronutrients intake through dietary diversity, MMS and fortified foods.

Iodine Nutrition Status of Children Aged 3–13 Years in Areas with High Groundwater Iodine Content in China

Iodine Nutrition Status of Children Aged 3–13 Years in Areas with High Groundwater Iodine Content in China

Iodine Nutritional Status and Thyroid Autoimmunity in Chinese Children and Adolescents Aged 6-17 Years.

Background: Thyroid autoimmunity (TAI), marked by thyroid peroxidase antibodies (TPOAb) and thyroglobulin antibodies (TgAb), affects over 10% of the general population, with children and adolescents experiencing significant impacts on growth and quality of life despite lower prevalence rates compared to adults. Methods: In the context of over 20 years of universal salt iodization (USI) in China, this study investigated the relationship between iodine nutritional status and TAI in children and adolescents aged 6-17. Results: Our findings suggest that while iodine levels are generally sufficient (median urinary iodine concentration [UIC] was 205.2 µg/L), TAI remains a significant concern due to its potential impact on growth and development. TAI was significantly associated with age, sex, and urban-rural residency (p < 0.05). Positive TPOAb and TgAb were identified as risk factors for subclinical hypothyroidism (OR = 2.274, 95% CI: 1.171-1.916). Although some literature suggests that excessive iodine may exacerbate TAI and others propose iodine deficiency as a risk factor, this study did not find a significant overall association between iodine status and TAI. Notably, a low urinary iodine-to-creatinine ratio (UI/Cr) level was linked to an increased risk of TgAb positivity in males (OR = 3.470, 95% CI: 1.200-10.036). In individuals with negative thyroid antibodies, increased BMI (OR = 1.062, 95% CI: 1.032-1.093) and high UI/Cr levels (OR = 1.510, 95% CI: 1.175-1.941) were risk factors for subclinical hypothyroidism, whereas older age (OR = 0.710, 95% CI: 0.555-0.908 for the age 9-11 group; OR = 0.681, 95% CI = 0.484-0.959 for the age 12-17 group) and high UIC levels (OR = 0.739, 95% CI: 0.554-0.985) were associated with reduced risk. No significant associations were observed in the thyroid antibody-positive group. Conclusions: These results highlight the importance of considering individual TAI status when devising iodine supplementation policies.