Recommendation and intake of dietary supplements periconceptional and during pregnancy: results of a nationwide survey of gynaecologists.

BACKGROUND: Micronutrient supplementation during pregnancy is a controversial issue. For some micronutrients, for example folic acid or iodine, the evidence regarding supplementation is clear, whereas for others, such as zinc or vitamin E, it is not. Studies show that a large number of pregnant women have deficient levels of folic acid and iodine. However, especially with folic acid, starting supplementation during the preconception period is crucial. It is, therefore, important that gynaecologists explain this to their pregnant or preconceptional patients. Our goal was to find out how gynaecologists make their recommendations on this topic, how they assess the compliance of their patients and which micronutrients they consider to be important before/during pregnancy and during breastfeeding. METHOD AND RESULTS: We sent about 12,000 questionnaires to all registered resident gynaecologists in Germany, with a response rate of 12.2%. Regarding which micronutrients gynaecologists  consider to be particularly important during pregnancy, there was a broad agreement for both folic acid and iodine (> 88% answered yes). According to the questionnaire, doctors rate other micronutrients, such as vitamin D and omega-3 fatty acids, as less essential. The controversial evidence level for many micronutrients certainly plays a role here. Overall, the intake rate, especially for preconceptional women, is classified as rather low (< 60%). The most widely valued reason is the high price of dietary supplements. It was also noticeable that doctors consider certain micronutrients to be particularly important but then do not include them in the products they recommend. CONCLUSION: Overall, there seems to be uncertainty about micronutrients in pregnancy and their supplementation. The study situation is often ambiguous and there are no official guidelines, leading to ambiguous recommendations from doctors and therefore low intake rates for pregnant or preconceptional women.

Re-exploring the requirement of dietary iodine intake in Chinese female adults based on 'iodine overflow theory'.

PURPOSE: We re-explored the basal iodine requirement based on healthy Chinese female and a new iodine overflow theory was proposed for iodine balance study. METHODS: Thirty-six Chinese healthy female adults (age 20.7 ± 1.1) were recruited for this study, which included 40 days low iodine depletion period and six stages of 30 days supplementation period. Uniform diets with low iodine were provided and the content of iodine in the diet was regulated by dairy products. The total iodine intake from food and the total iodine excretion through 24-h urine and staged feces were completely gathered and monitored. The incremental (Δ) intake and excretion over the range were calculated. RESULTS: The iodine intake and excretion were 13.6 µg/day and 48.6 µg/day at the first stage, respectively. The incremental iodine intakes and excretions were 21.1 µg/day to 120.3 µg/day and 25.8 µg/day to 105.4 µg/day for the supplementation stages, respectively. According to the 'iodine overflow theory', the zero iodine balance (Δ iodine intake = Δ iodine excretion) derived from a mixed effect model indicated a mean iodine intake of 52.2 µg/d (1.0 µg/d kg). The RNI for iodine to healthy Chinese female adult was 73.1 µg/d (1.4 µg/d kg). CONCLUSION: A daily iodine intake of 52.2 µg/d may meet the basal iodine requirement for healthy Chinese female adults, and Chinese female may need more than 20% iodine intake than male based on the 'iodine overflow theory'. The trial was registered at the Chinese Clinical Trial Registry in May 2018 (No: ChiCTR1800016184).

Do Micronutrient and Omega-3 Fatty Acid Supplements Affect Human Maternal Immunity during Pregnancy? A Scoping Review.

Maternal dietary micronutrients and omega-3 fatty acids support development of the fetal and neonatal immune system. Whether supplementation is similarly beneficial for the mother during gestation has received limited attention. A scoping review of human trials was conducted looking for evidence of biochemical, genomic, and clinical effects of supplementation on the maternal immune system. The authors explored the literature on PubMed, Cochrane Library, and Web of Science databases from 2010 to the present day using PRISMA-ScR methodology. Full-length human trials in English were searched for using general terms and vitamin A, B12, C, D, and E; choline; iodine; iron; selenium; zinc; and docosahexaenoic/eicosapentaenoic acid. Of 1391 unique articles, 36 were eligible for inclusion. Diverse biochemical and epigenomic effects of supplementation were identified that may influence innate and adaptive immunity. Possible clinical benefits were encountered in malaria, HIV infections, anemia, Type 1 diabetes mellitus, and preventing preterm delivery. Only limited publications were identified that directly explored maternal immunity in pregnancy and the effects of micronutrients. None provided a holistic perspective. It is concluded that supplementation may influence biochemical aspects of the maternal immune response and some clinical outcomes, but the evidence from this review is not sufficient to justify changes to current guidelines.

Consumer Acceptance and Market Potential of Iodine-Biofortified Fruit and Vegetables in Germany.

Biofortification of food crops with iodine is a novel approach to preventing iodine deficiency in humans. The present study analyses the consumer target groups and the market potential of iodine-biofortified fruit and vegetables in Germany. For this purpose, an online survey of 1016 German fruit and vegetable consumers was conducted to investigate the acceptance of different product categories as well as relevant criteria for the market launch. The results show that iodine-biofortified fruit and vegetables are particularly attractive to consumers who purchase at farmers' markets, organic food shops, and farm stores. Out of this group, 39% of consumers rate such iodine-rich foods as very appealing. They attach importance to food that naturally contains iodine and prefer produce from integrated domestic cultivation. With their focus on sustainability and naturalness, this group of consumers clearly differs from typical users of dietary supplements, who are primarily concerned with health benefits. However, overall about 85% of respondents would prefer biofortified fruits and vegetables to supplements to improve their iodine supply. The greatest market potential for iodine-biofortified fruit and vegetables is to be expected in supermarkets, as this is the preferred food shopping location for most consumers. A total of 28% of those who buy here rate the biofortified foods presented as very appealing. Nevertheless, a successful market launch requires that the benefits of the new products are communicated according to the potential consumer group needs.

The Nutritional Supply of Iodine and Selenium Affects Thyroid Hormone Axis Related Endpoints in Mice.

Selenium and iodine are the two central trace elements for the homeostasis of thyroid hormones but additional trace elements such as iron, zinc, and copper are also involved. To compare the primary effects of inadequate intake of selenium and iodine on the thyroid gland, as well as the target organs of thyroid hormones such as liver and kidney, mice were subjected to an eight-week dietary intervention with low versus adequate selenium and iodine supply. Analysis of trace element levels in serum, liver, and kidney demonstrated a successful intervention. Markers of the selenium status were unaffected by the iodine supply. The thyroid gland was able to maintain serum thyroxine levels even under selenium-deficient conditions, despite reduced selenoprotein expression in liver and kidney, including deiodinase type 1. Thyroid hormone target genes responded to the altered selenium and iodine supply, whereas the iron, zinc, and copper homeostasis remained unaffected. There was a notable interaction between thyroid hormones and copper, which requires further clarification. Overall, the effects of an altered selenium and iodine supply were pronounced in thyroid hormone target tissues, but not in the thyroid gland.

Effects of Molecular Iodine/Chemotherapy in the Immune Component of Breast Cancer Tumoral Microenvironment.

Molecular iodine (I2) induces apoptotic, antiangiogenic, and antiproliferative effects in breast cancer cells. Little is known about its effects on the tumor immune microenvironment. We studied the effect of oral (5 mg/day) I2 supplementation alone (I2) or together with conventional chemotherapy (Cht+I2) on the immune component of breast cancer tumors from a previously published pilot study conducted in Mexico. RNA-seq, I2 and Cht+I2 samples showed significant increases in the expression of Th1 and Th17 pathways. Tumor immune composition determined by deconvolution analysis revealed significant increases in M0 macrophages and B lymphocytes in both I2 groups. Real-time RT-PCR showed that I2 tumors overexpress T-BET (p = 0.019) and interferon-gamma (IFNγ; p = 0.020) and silence tumor growth factor-beta (TGFß; p = 0.049), whereas in Cht+I2 tumors, GATA3 is silenced (p = 0.014). Preliminary methylation analysis shows that I2 activates IFNγ gene promoter (by increasing its unmethylated form) and silences TGFß in Cht+I2. In conclusion, our data showed that I2 supplements induce the activation of the immune response and that when combined with Cht, the Th1 pathways are stimulated. The molecular mechanisms involved in these responses are being analyzed, but preliminary data suggest that methylation/demethylation mechanisms could also participate.

XB130 Deficiency Causes Congenital Hypothyroidism in Mice due to Disorganized Apical Membrane Structure and Function of Thyrocytes.

Background: Congenital hypothyroidism is often caused by genetic mutations that impair thyroid hormone (TH) production, resulting in growth and development defects. XB130 (actin filament associated protein 1 like 2) is an adaptor/scaffold protein that plays important roles in cell proliferation, migration, intracellular signal transduction, and tumorigenesis. It is highly expressed in thyrocytes, however, its function in the thyroid remains largely unexplored. Methods:Xb130-/- mice and their littermates were studied. Postnatal growth and growth hormone levels were measured, and responses to low or high-iodine diet, and levothyroxine treatment were examined. TH and thyrotropin in the serum and TH in the thyroid glands were quantified. Structure and function of thyrocytes in embryos and postnatal life were studied with histology, immunohistochemistry, immunofluorescence staining, Western blotting, and quantitative reverse transcription polymerase chain reaction. Results:Xb130-/- mice exhibited transient growth retardation postnatally, due to congenital hypothyroidism with reduced TH synthesis and secretion, which could be rescued by exogenous thyroxine supplementation. The thyroid glands of Xb130-/- mice displayed diminished thyroglobulin iodination and release at both embryonic and early postnatal stages. XB130 was found mainly on the apical membrane of thyroid follicles. Thyroid glands of embryonic and postnatal Xb130-/- mice exhibited disorganized apical membrane structure, delayed folliculogenesis, and abnormal formation of thyroid follicle lumina. Conclusion: XB130 critically regulates folliculogenesis by maintaining apical membrane structure and function of thyrocytes, and its deficiency leads to congenital hypothyroidism.

Assessment of the contribution of industrially processed foods to salt and iodine intake in Thailand.

Iodization of food grade salt has been mandated in Thailand since 1994. Currently, processed food consumption is increasing, triggered by higher income, urbanization, and lifestyle changes, which affects the source of salt and potentially iodized salt among the population. However, adequate information about the use of iodized salt in processed foods in Thailand is still lacking. Therefore, this study aimed to assess iodine intake through salt-containing processed foods and condiments which were identified using national survey data. Potential iodine intake from iodized salt in food products was modelled using consumption data and product salt content from food labelling and laboratory analysis. Fish sauce, soy sauce and seasoning sauces (salty condiments) have alternative regulation allowing for direct iodization of the final product, therefore modelling was conducted including and excluding these products. Daily salt intake from household salt and food industry salt (including salty condiments) was estimated to be 2.4 g for children 0-5 years of age, 4.6 g for children 6-12 years of age, and 11.5 g for adults. The use of iodized salt in processed foods (excluding salty condiments) met approximately 100% of the estimated average requirement (EAR) for iodine for non-pregnant adults and for children 6 to 12 years of age, and 50% of the EAR for iodine for children aged 0 to 5 years of age. In all cases, iodine intake from processed food consumption was greater than from estimated household iodized salt consumption. Findings suggest that iodized salt from processed foods is an important source of iodine intake, especially in adults. The use of iodized salt by the food industry should be enforced along with population monitoring to ensure sustainability of optimal iodine intake. Currently, the addition of iodine into fish sauce, soy sauce and seasoning sauces has an important role in achieving and sustaining optimal iodine intake.

Pre-Launch Exploration of Consumer Willingness to Purchase Selenium- and Iodine-Biofortified Apples-A Discrete Choice Analysis of Possible Market Settings.

Selenium and iodine are essential micronutrients for humans. They are often deficient in food supply due to low phytoavailable concentrations in soil. Agronomic biofortification of food crops is one approach to overcome micronutrient malnutrition. This study focused on a pre-launch exploration of German consumers' willingness to purchase selenium- and/or iodine-biofortified apples. For this purpose, an online survey was carried out. In this context, consumers were asked to choose their most preferred apple product from a set card of product alternatives in a discrete choice experiment (DCE). The multinomial logit model results demonstrated that German consumers' have a particular preference for iodine-biofortified apples. Furthermore, apple choice was mainly influenced by price, health claims, and plastic-free packaging material. Viewed individually, selenium did not exert an effect on product choice whereas positive interactions between both micronutrients exist.

Excessive Prenatal Supplementation of Iodine and Fetal Goiter: Report of Two Cases Using Three-dimensional Ultrasound and Magnetic Resonance Imaging.

Fetal thyroid complications in pregnancy are uncommon, and are commonly related to the passage of substances through the placenta. The excessive iodine intake during the pregnancy is a well-known mechanism of fetal thyroid enlargement or goiter, and invasive procedures have been proposed for the treatment of fetal thyroid pathologies. In the present report, we demonstrate two cases from different centers of prenatal diagnosis of fetal thyroid enlargement and/or goiter in three fetuses (one pair of twins, wherein both fetuses were affected, and one singleton pregnancy). The anamnesis revealed the ingestion of iodine by the patients, prescribed from inadequate vitamin supplementation. In both cases, the cessation of iodine supplement intake resulted in a marked reduction of the volume of the fetal thyroid glands, demonstrating that conservative treatment may be an option in those cases. Also, clinicians must be aware that patients may be exposed to harmful dosages or substances during pregnancy.

As complicações fetais da tireoide na gravidez são incomuns e são comumente relacionadas à passagem de substâncias pela placenta. A ingestão excessiva de iodo durante a gravidez é um mecanismo bem conhecido de aumento da tireoide ou bócio fetal, e procedimentos invasivos foram propostos para o tratamento de patologias da tireoide fetal. No presente relato de caso, demonstramos dois casos de diferentes centros de diagnóstico pré-natal de aumento da tireoide fetal e/ou bócio em três fetos (um par de gêmeos, em que ambos os fetos foram afetados, e uma gravidez única). A anamnese revelou a ingestão de iodo pelos pacientes prescrita por suplementação inadequada de vitaminas. Nos dois casos, a interrupção da ingestão de suplemento de iodo resultou em uma redução acentuada do volume das glândulas tireoides fetais, demonstrando que o tratamento conservador pode ser uma opção nestes casos. Além disso, os médicos devem estar cientes de que as pacientes podem ser expostas a doses ou substâncias nocivas durante a gravidez.

Excessive prenatal supplementation of iodine and fetal goiter: report of two cases using three-dimensional ultrasound and magnetic resonance imaging / Suplementação pré-natal excessiva de iodo e bócio fetal: Relato de dois casos utilizando ultrassonografia tridimensional e ressonância magnética

Abstract Fetal thyroid complications in pregnancy are uncommon, and are commonly related to the passage of substances through the placenta. The excessive iodine intake during the pregnancy is a well-known mechanism of fetal thyroid enlargement or goiter, and invasive procedures have been proposed for the treatment of fetal thyroid pathologies. In the present report, we demonstrate two cases from different centers of prenatal diagnosis of fetal thyroid enlargement and/or goiter in three fetuses (one pair of twins, wherein both fetuses were affected, and one singleton pregnancy). The anamnesis revealed the ingestion of iodine by the patients, prescribed from inadequate vitamin supplementation. In both cases, the cessation of iodine supplement intake resulted in a marked reduction of the volume of the fetal thyroid glands, demonstrating that conservative treatmentmay be an option in those cases. Also, clinicians must be aware that patients may be exposed to harmful dosages or substances during pregnancy.

Resumo As complicações fetais da tireoide na gravidez são incomuns e são comumente relacionadas à passagem de substâncias pela placenta. A ingestão excessiva de iodo durante a gravidez é um mecanismo bem conhecido de aumento da tireoide ou bócio fetal, e procedimentos invasivos foram propostos para o tratamento de patologias da tireoide fetal. No presente relato de caso, demonstramos dois casos de diferentes centros de diagnóstico pré-natal de aumento da tireoide fetal e/ou bócio em três fetos (um par de gêmeos, em que ambos os fetos foram afetados, e uma gravidez única). A anamnese revelou a ingestão de iodo pelos pacientes prescrita por suplementação inadequada de vitaminas. Nos dois casos, a interrupção da ingestão de suplemento de iodo resultou em uma redução acentuada do volume das glândulas tireoides fetais, demonstrando que o tratamento conservador pode ser uma opção nestes casos. Além disso, os médicos devem estar cientes de que as pacientes podem ser expostas a doses ou substâncias nocivas durante a gravidez.

Iodine supplementation for pregnant women: a cross-sectional national interventional study.

BACKGROUND: Although Iran has been considered iodine replete since 2000, the first national survey of iodine intake among Iranian pregnant women in 2014 indicated that despite the adequate intake of iodine by the general population, this vulnerable group has moderate iodine deficiency. Therefore, in this national cross-sectional interventional study, we aimed to assess the iodine intake and thyroid function of Iranian pregnant women 2 years after implementing national iodine supplementation for this vulnerable group. MATERIALS AND METHODS: In this cross-sectional study, we conducted a national interventional survey of pregnant women. A total of 1200 pregnant women (400 women from each trimester) from 12 provinces of Iran were recruited from the antenatal care clinics from October 2018 to March 2019. The median urinary iodine concentration (MUIC), as an indicator of iodine status in three spot urine samples, was measured, along with the serum total T4 (TT4), thyrotropin (TSH), thyroglobulin (Tg), thyroid peroxidase antibody (TPO-Ab), and iodine content of household salt. RESULTS: The mean age of the cohort was 28 ± 6.2 years, with the mean gestational age of 22.7 ± 13.0 weeks. The overall MUIC (IQR) of pregnant women was 188 µg/L (124.2-263 µg/L). Also, the MUICs in the three trimesters of pregnancy were 174 µg/L (110-254), 175 µg/L (116-251), and 165 µg/L (114-235), respectively. The MUICs ≥ 150, 100-149, and < 100 µg/L were found in 63, 19.8, and 16.2% of the subjects, respectively. The mean TT4 level was 12 ± 4.5 µg/dL, and the median (IQR) level of TSH was 2.37 mIU/L (1.66-3.18 mIU/L). According to our local reference range, 118 (10.5%) pregnant women had subclinical hypothyroidism, 6 (0.53%) women had isolated hypothyroxinemia, and 65 (5.7%) women were TPO-Ab positive. Also, the median (IQR) level of Tg was 10.08 µg/dL (5.7-20.4 µg/dL), and the median iodine content of household salt was 29.6 µg/g; the iodine content was ≥ 30 µg/g in 85% of household salt. The results showed that more than 95% of households were under iodized salt coverage. CONCLUSION: The results of this study indicated that iodine supplementation with at least 150 µg of iodine per day improved the iodine intake of pregnant women. Except for subclinical hypothyroidism, the prevalence of clinical hypothyroidism, clinical/subclinical thyrotoxicosis, TPO-Ab positivity, and isolated hypothyroxinemia decreased significantly, which emphasizes the importance of iodine supplementation during pregnancy.

The Double-Fortified Salt (Iodized Salt with Iron) Consultation: A Process for Developing Evidence-Based Considerations for Countries.

The addition of iodine to edible salt has been one of the most important public health successes of the past half century, enabling most countries to achieve optimal iodine intake and protect the brains of unborn children from the adverse consequences of iodine deficiency. Salt has been an ideal vehicle for this effort because of its near universal and narrow range of consumption, relative ease of technology for salt iodization, and capacity for virtually all salt producers to add iodine. As a result of the success of salt iodization, there has been growing interest in using salt as a vehicle for other important micronutrients, particularly the addition of iron to iodized salt to produce double-fortified salt (DFS), to combat the persistent problem of iron deficiency and iron deficiency anemia. Because of this growing interest in DFS and the need for a comprehensive review of evidence to support the viability of this intervention, the Iodine Global Network (IGN) initiated a global consultation to gather all available data on different aspects of DFS. IGN identified 4 key areas considered essential to understand for a successful fortification intervention: 1) efficacy and effectiveness, or how well DFS produces a health impact in controlled and real-life settings; 2) technical considerations for production, or what are the minimum requirements to manufacture DFS; 3) program implementation to describe experiences thus far with the delivery of DFS across multiple platforms; and 4) comparison of DFS with other iron fortification efforts to determine the comparative advantage of DFS to improve iron intake and prevent iron deficiency anemia. This preface provides an overview of the DFS Consultation objectives, process, and objectives.

Evaluation of Global Experiences in Large-Scale Double-Fortified Salt Programs.

BACKGROUND: Double-fortified salt (DFS) is a vehicle for dual fortification with iron and iodine, to reduce their respective deficiencies. This background article is the third in a series reviewing available research, analyses, and experiences on DFS as an effective delivery vehicle for iron and iodine. OBJECTIVES: The objective of this article is to systematically evaluate current programs distributing DFS around the world and catalogue opportunities, risks, and challenges related to programs that incorporate DFS. We carried out a narrative review of DFS programs from around the world with our data sources deriving from a mix of a nonsystematic literature search and interviews with key informants. METHODS: We assessed programmatic experience with DFS from social safety net programs in India (from the states of Bihar, Madhya Pradesh, and Uttar Pradesh) and from non-social safety net country programs or projects in Argentina, Cote d'Ivoire, Kenya, Morocco, Nigeria, Philippines, and Sri Lanka. RESULTS: Findings revealed color change of the final DFS product was an issue in 9 of the 14 programs or studies reviewed and was the most significant challenge that had a direct impact on consumer acceptance and uptake regardless of type of program (open market or social safety net). Other challenges identified were related to the quality of the salt and lack of DFS formulation standards and regulatory monitoring protocols. CONCLUSIONS: DFS programs need to focus on 1) improved technology with better consumer acceptance and better performance when used with lower-quality salt; 2) elucidation and enforcement of DFS formulation quality standards, along with producer incentives; and 3) strong government backing at the policy level. DFS offers a unique opportunity to leverage an almost universally consumed product with the addition of 2 important nutrients missing in many populations. However, program "maturity" will take time with urgent attention needed for quality production.

Effect of potassium iodide supplementation and teat-dipping on iodine status in dairy cows and milk iodine levels.

Two experiments were designed to determine the effects of dietary iodine and teat-dipping on the iodine status of dairy cows and their milk. Eight mid-lactation Holstein dairy cows with an initial body weight of 642 ± 62 kg and 145 ± 21 d in milk were studied for 2 periods over 44 d. In period 1, all cows were fed a basal diet supplemented with potassium iodide (KI) (10 mg I/Kg DM) for 8 d with no teat-dipping. In period 2, a pre-milking teat-dipping was applied for 10 d followed by no teat-dipping before milking (udder wash without iodine) and then post-dipping treatment was applied for 5 d. Feeding KI increased concentrations of iodine in serum, urine, and milk (P < 0.05). Switching from the KI supplementation to no iodine addition resulted in an immediate decrease of iodine in serum, urine, and milk (P < 0.05). Post teat-dipping resulted in increased iodine levels in serum, urine, and milk (P < 0.05). However, pre-milking teat-dipping did not affect iodine concentration compared to post-dipping. A 250 mL cup of milk from the control and KI-supplemented diets would provide 29.4% and 68.4%, respectively, of the adult-recommended dietary allowance for iodine. In conclusion, milk iodine concentration could be effectively enhanced by KI supplementation and teat-dipping practices.

Prevalence of inadequate and excessive iodine intake in a US pregnancy cohort.

BACKGROUND: US iodine intake, estimated from the median urinary iodine concentration of population representative data, has declined by half since the 1970s, which is problematic because maternal iodine intake is critical for fetal neurodevelopment. Relying on median urinary concentrations to assess iodine intake of populations is standard practice but does not describe the number of individuals with insufficient intake. Prevalence estimates of inadequate and excessive intake are better for informing public health applications but require multiple urine samples per person; such estimates have been generated in pediatric populations but not yet among pregnant women. OBJECTIVE: Our aims were as follows: (1) to assess median urinary iodine concentrations across pregnancy for comparison with national data and (2) to estimate the prevalence of inadequate and excessive iodine intake among pregnant women in mid-Michigan. STUDY DESIGN: Data were collected from 2008 to 2015 as part of a prospective pregnancy cohort in which women were enrolled at their first prenatal clinic visit. Few exclusion criteria (<18 years or non-English speaking) resulted in a sample of women generally representative of the local community, unselected for any specific health conditions. Urine specimens were obtained as close as practicable to at least 1 specimen per trimester during routine prenatal care throughout pregnancy (n=1-6 specimens per woman) and stored at -80°C until urinary iodine was measured to estimate the iodine intake (n=1014 specimens from 464 women). We assessed urinary iodine across pregnancy by each gestational week of pregnancy and by trimester. We used multiple urine specimens per woman, accounted for within-person variability, performed data transformation to approximate normality, and estimated the prevalence of inadequate and excessive iodine intake using a method commonly employed for assessment of nutrient status. RESULTS: Maternal characteristics reflected the local population in racial and ethnic diversity and socioeconomic status as follows: 53% non-Hispanic white, 22% non-Hispanic black, and 16% Hispanic; 48% had less than or equal to high school education and 71% had an annual income of <$25,000. Median urinary iodine concentrations in the first, second, and third trimester-including some women contributing more than 1 specimen per trimester-were 171 µg/L (n=305 specimens), 181 µg/L (n=366 specimens), and 179 µg/L (n=343 specimens), respectively, with no significant difference by trimester (P=.50, Kruskal-Wallis test for equality of medians). The estimated prevalence of inadequate and excessive iodine intake was 23% and <1%, respectively. CONCLUSION: Median urinary iodine concentrations in each trimester were above the World Health Organization cutoff of 150 µg/L, indicating iodine sufficiency at the group level across pregnancy. However, the estimated prevalence of inadequate iodine intake was substantial at 23%, whereas prevalence of excessive intake was <1%, indicating a need for at least some women to increase consumption of iodine during pregnancy. The American Thyroid Association, the Endocrine Society, and the American Academy of Pediatrics recommend that all pregnant and lactating women receive a daily multivitamin or mineral supplement that contains 150 µg of iodine. The data presented here should encourage the collection of similar data from additional US population samples for the purpose of informing the American College of Obstetricians and Gynecologists' own potential recommendations for prenatal iodine supplementation.

Effects of iodine supplementation during pregnancy on pregnant women and their offspring: a systematic review and meta-analysis of trials over the past 3 decades.

OBJECTIVE: The current systematic review aimed to provide comprehensive data on the effects of iodine supplementation in pregnancy and investigate its potential benefits on infant growth parameters and neurocognitive development using meta-analysis. METHODS: A systematic review was conducted on trials published from January 1989 to December 2019 by searching MEDLINE, Web of Science, the Cochrane Library, Scopus, and Google Scholar. For most maternal and neonatal outcomes, a narrative synthesis of the data was performed. For birth anthropometric measurements and infant neurocognitive outcomes, the pooled standardized mean differences (SMDs) with 95% CIs were estimated using fixed/random effect models. RESULTS: Fourteen trials were eligible for inclusion in the systematic review, of which five trials were included in the meta-analysis. Although the findings of different thyroid parameters are inconclusive, more consistent evidence showed that iodine supplementation could prevent the increase in thyroglobulin concentration during pregnancy. In the meta-analysis, no differences were found in weight (-0.11 (95% CI: -0.23 to 0.01)), length (-0.06 (95% CI: -0.21 to 0.09)), and head circumference (0.26 (95% CI: -0.35 to 0.88)) at birth, or in cognitive (0.07 (95% CI: -0.07 to 0.20)), language (0.06 (95% CI: -0.22 to 0.35)), and motor (0.07 (95% CI: -0.06 to 0.21)) development during the first 2 years of life in infants between the iodine-supplemented and control groups. CONCLUSION: Iodine supplementation during pregnancy can improve the iodine status in pregnant women and their offspring; however, according to our meta-analysis, there was no evidence of improved growth or neurodevelopmental outcomes in infants of iodine-supplemented mothers.

Supplemental iodine-containing prenatal multivitamins use and the potential effects on pregnancy outcomes in a mildly iodine-deficient region.

PURPOSE: The use and contribution of prenatal multivitamins (PMV) as iodine source for pregnant women in China, especially in mildly iodine-deficient region, have not been well studied. This study aimed to explore the association between PMV intake during pregnancy and thyroid function in mothers and newborns. METHODS: We performed a study involving women with a history of taking PMV during pregnancy between January 2013 and October 2015, in Shanghai, a mildly iodine-deficient region. Maternal thyroid function in early and late pregnancy, and neonatal TSH on postnatal d 3 were obtained from medical records. We compared the outcomes in pregnant women who took exclusively iodine-containing PMV (I + PMV) with those who took exclusively non-contained PMV (I- PMV). Propensity score matching (PSM) was used to identify women with similar baseline characteristics. RESULTS: After PSM, 1280 women in I + PMV and 2560 in I- PMV had similar propensity scores and were included in the analyses. Introduction of I + PMV to women was associated with slightly higher maternal thyroid hormone production (higher maternal FT4, p = 0.01, non-significantly lower TSH, p = 0.79) and lower neonatal TSH levels (p < 0.0001). The frequency of adverse pregnancy outcomes or thyroid dysfunctions did not differ between groups in late pregnancy. Mothers received I + PMV (0.2 SD) had a stronger association of maternal TSH with neonatal TSH than those who received I- PMV (0.1 SD). These effects were only shown in TPOAb-negative mothers, not in TPOAb-positive mothers. CONCLUSION: TPOAb-positive women display an impaired iodine transport in thyroid and placenta, and this may explain the lack of changes in maternal and neonatal thyroid parameters with I + PMV supplementation in these women. This phenomenon might suggest that these women require different iodine doses or treatment approach in comparison with TPOAb-negative women.

The effects of salt consumption habits on iodine status and thyroid functions during pregnancy

Background/aim: Iodine is the basic substrate for thyroid hormone synthesis and is vital for the general population and especially pregnant women. Iodine deficiency may cause severe health problems for a foetus. This study aimed to determine the relationship, if any, between iodine level and thyroid function tests, and to determine the relationship between consumption of salt types and its effects on thyroid function tests in the first trimester of pregnancy. Materials and methods: Three hundred and six pregnant women in the first trimester of pregnancy, who had known no thyroid disease history and had not received iodine supportive therapy, were included in the study. All patients were questioned for their preferred table salt or rock salt in daily use and urine iodine concentrations (UICs) were analysed in spot urine. The results were evaluated statistically according to salt usage preferences. Results: The median age of patients in the study was 27.8 (± 5.4). In terms of salt consumption habits, 235 (76.8%) of patients reported using table salt, and 71 (23.2%) reported using rock salt. Iodine deficiency was found in 75.81% (n = 232) of all cases according to urinalysis. Median UICs of table salt group were significantly higher than rock salt group (123.7 µg/L and 70.9 µg/L respectively, P < 0.001). Conclusion: Although large-scale salt iodination began long time ago, iodine deficiency is still a serious health problem among pregnant women. According to this study, use of rock salt is associated with low urinary iodine concentration in pregnant women and TSH values within the reference limits are not a good indicator for determining the iodine level.

Micronutrients and Breast Cancer Progression: A Systematic Review.

Epidemiological studies on micronutrient consumption have reported protective associations in the incidence and/or progression of various cancer types. Supplementation with some of these micronutrients has been analyzed, showing chemoprotection, low toxicity, antiproliferation, and the ability to modify epigenetic signatures in various cancer models. This review investigates the reported effects of micronutrient intake or supplementation in breast cancer progression. A PubMed search was conducted with the keywords "micronutrients breast cancer progression", and the results were analyzed. The selected micronutrients were vitamins (C, D, and E), folic acid, metals (Cu, Fe, Se, and Zn), fatty acids, polyphenols, and iodine. The majority of in vitro models showed antiproliferative, cell-cycle arrest, and antimetastatic effects for almost all the micronutrients analyzed, but these effects do not reflect animal or human studies. Only one clinical trial with vitamin D and one pilot study with molecular iodine showed favorable overall survival and disease-free interval.