Mothers’ behaviour contributes to suboptimal iodine status of family members: findings from an iodine-sufficient area

AbstractObjectiveIodine deficiency still remains a major public health concern worldwide despite global progress in its elimination. The aims of the present study were to evaluate dietary iodine status in the mother and one adult member of each family and the association between mothers’ knowledge, attitude and behaviour and the dietary iodine status of adult family members in Tehran.DesignIn this cross-sectional study, 24 h urinary iodine and Na concentrations and the iodine content of household salt were measured. Mothers’ knowledge, attitude and behaviour were assessed using a questionnaire administered in face-to-face interviews.SettingHealth-care centres from four distinct areas of Tehran.SubjectsMother–adult family member pairs aged ≥19 years (n 290), enrolled through randomized cluster sampling.ResultsIn mothers and adult family members, median 24 h urinary iodine concentration was 73 (interquartile range (IQR) 36–141) µg/l and 70 (IQR 34–131) µg/l, dietary iodine intake was 143 (IQR 28–249) µg/d and 130 (IQR 26–250) µg/d and dietary salt intake was 8·0 (IQR 5·9–10·2) g/d and 7·5 (IQR 5·3–10·0) g/d, respectively. Significant correlations were observed between mothers’ attitude and behaviour and the 24 h urinary iodine concentration, dietary iodine intake and iodine content of salt of adult family members. In multiple analysis, lower quartiles of salt iodine content and salt intake and inappropriate behaviour scores in mothers increased the risk of urinary iodine concentration <100 µg/l in adult family members.ConclusionsThe present study showed that mothers’ behaviour, but not knowledge and attitude, was among major contributors to the suboptimal dietary iodine status observed in adult family members.

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

Nutrients ◽

10.3390/nu12113483 ◽

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.

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

British Journal Of Nutrition ◽

10.1017/s0007114520003876 ◽

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.

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

Nutrients ◽

10.3390/nu12082399 ◽

2020 ◽

Vol 12 (8) ◽

pp. 2399 ◽

Cited By ~ 1

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.

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

Mediscope ◽

10.3329/mediscope.v5i2.37146 ◽

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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The assessment of iodine status – populations, individuals and limitations

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/0004563218774816 ◽

2018 ◽

Vol 56 (1) ◽

pp. 7-14 ◽

Cited By ~ 3

Author(s):

Patrick Wainwright ◽

Paul Cook

Keyword(s):

Iodine Deficiency ◽

Urinary Iodine ◽

Population Level ◽

Iodine Concentration ◽

Epidemiological Studies ◽

Health Concern ◽

Urinary Iodine Concentration ◽

Iodine Status ◽

The Uk

Iodine deficiency is a significant global health concern, and the single greatest cause of preventable cognitive impairment. It is also a growing public health concern in the UK particularly among pregnant women. Biomarkers such as urinary iodine concentration have clear utility in epidemiological studies to investigate population-level iodine status, but determination of iodine status in individuals is much more problematic with current assays. This article reviews the available biomarkers of iodine status and their relative utility at the level of both populations and individuals for the investigation of iodine deficiency and iodine excess.

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Assessment of the iodine nutritional status among Chinese school-aged children

Endocrine Connections ◽

10.1530/ec-19-0568 ◽

2020 ◽

Vol 9 (5) ◽

pp. 379-386

Author(s):

Ning Yao ◽

Chunbei Zhou ◽

Jun Xie ◽

Xinshu Li ◽

Qianru Zhou ◽

...

Keyword(s):

Nutritional Status ◽

Urinary Iodine ◽

Thyroid Volume ◽

Iodine Content ◽

Iodine Concentration ◽

Iodine Intake ◽

Iodized Salt ◽

Urinary Iodine Concentration ◽

School Aged Children ◽

Goiter Prevalence

Objective The remarkable success of iodine deficiency disorders (IDD) elimination in China has been achieved through a mandatory universal salt iodization (USI) program. The study aims to estimate the relationship between urinary iodine concentration (UIC) and iodine content in edible salt to assess the current iodine nutritional status of school aged children. Methods A total of 5565 students from 26 of 39 districts/counties in Chongqing participated in the study, UIC and iodine content in table salt were measured. Thyroid volumes of 3311 students were examined by ultrasound and goiter prevalence was calculated. Results The overall median UIC of students was 222 μg/L (IQR: 150-313 μg/L). Median UIC was significantly different among groups with non-iodized salt (iodine content <5 mg/kg), inadequately iodized salt (between 5 and 21 mg/kg), adequately iodized (between 21 and 39 mg/kg) and excessively iodized (>39 mg/kg) salt (P < 0.01). The total goiter rate was 1.9% (60/3111) and 6.0% (186/3111) according to Chinese national and WHO reference values, respectively. Thyroid volume and goiter prevalence were not different within the three iodine nutritional status groups (insufficient, adequate and excessive, P > 0.05). Conclusions The efficient implementation of current USI program is able to reduce the goiter prevalence in Chongqing as a low incidence of goiter in school aged children is observed in this study. The widened UIC range of 100–299 μg/L indicating sufficient iodine intake is considered safe with a slim chance of causing goiter or thyroid dysfunction. Further researches were needed to evaluate the applicability of WHO reference in goiter diagnose in Chongqing or identifying more accurate criteria of normal thyroid volume of local students in the future.

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Indicators of Iodine Status in Pregnancy and Postpartum in a Group of Pregnant Women from Perimarine Area of Romania

ARS Medica Tomitana ◽

10.2478/arsm-2020-0013 ◽

2020 ◽

Vol 26 (2) ◽

pp. 63-69

Author(s):

Scrinic Olesea ◽

Delia Corina Elena ◽

Toma Geanina Mirela ◽

Circo Eduard

Keyword(s):

Pregnant Women ◽

Iodine Deficiency ◽

Urinary Iodine ◽

Iodine Concentration ◽

Iodine Intake ◽

Iodized Salt ◽

Urinary Iodine Concentration ◽

Urinary Creatinine ◽

Iodine Status ◽

In Pregnancy

Abstract Objective: Assessment of iodine nutritional status in pregnant women in the perimarine area of Romania, a region without iodine deficiency. Adequate iodine intake is the main source for normal thyroid function, ensuring the need for maternal thyroid hormones during pregnancy, but also for the development and growth of children in the fetal and postpartum period. Material and method: Prospective study performed on 74 pregnant women in the first 2 trimesters of pregnancy, originating from the perimarin area. The following indicators of iodine status were analyzed: urinary iodine concentration (UIC), the ratio between urinary iodine concentration and urinary creatinine (UIC/UCr), the prevalence of maternal goiter and the value of neonatal TSH (thyroid stimulating hormone). Results: The mean gestational age was 11 weeks. The ways of iodine intake are: iodized salt - 59.4%, iodized salt and iodine supplements- 23%, only iodine supplements -10.8% and 6.8% consume only non-iodized salt. The median of UIC was 133.03 mcg/l considered insufficient iodine intake (normal in pregnancy UIC >150 mcg/l), but the adjustment of UIC to urinary creatinine reveals a median of 152.83 mcg/g, a value that reflects an adequate iodine intake. The prevalence of goiter was 25.6% characteristic for a moderate iodine deficiency. The prevalence of neonatal TSH >5 mIU/L was registered in 18.8% characteristic of mild iodine deficiency. Conclusions: Monitoring of the iodine nutritional status is recommended for the prevention of disorders due to iodine deficiency under the conditions of universal salt iodization. Perimarine areas considered sufficient in iodine may show variations in iodine status in subpopulations under certain physiological conditions, such as pregnancy. An indicator of iodine status of the population is UIC, but the UIC/UCr ratio may be a more optimal indicator for pregnant women, to avoid possible overestimated results of iodine deficiency in pregnancy.

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Current iodine status in Japan: A cross-sectional nationwide survey of schoolchildren, 2014–2019

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/clinem/dgab919 ◽

2021 ◽

Author(s):

Yozen Fuse ◽

Yoshiya Ito ◽

Yoshimasa Shishiba ◽

Minoru Irie

Keyword(s):

Urinary Iodine ◽

Nationwide Survey ◽

Iodine Concentration ◽

Iodine Intake ◽

Urinary Iodine Excretion ◽

Urinary Iodine Concentration ◽

Cross Sectional ◽

Iodine Status ◽

Iodine Excretion ◽

Cr Concentration

Abstract Context Japan has been regarded as a long-standing iodine sufficient country without iodine fortification; however, data on nationwide iodine status is lacking. Objective This study aimed to characterize the iodine status in Japan. Methods From 2014 through 2019 a nationwide school-based survey was conducted across all districts in Japan. Urinary iodine concentration (UIC), creatinine (Cr) concentration and anthropometry were assessed in healthy school-aged children (SAC) aged 6 to 12 years. Their iodine status is regarded as generally representative of the nation's iodine status. Results A total of 32,025 children participated. The overall median UIC was 269 μg/L which was within the WHO’s adequacy range. There was a regional difference in UIC values within 14 regions, and the lowest and highest median UIC were found in Tanegashima Island (209 μg/L) and Nakashibetsu, Hokkaido (1,071 μg/L), respectively. The median UIC ≥ 300 μg/L was observed in 12 out of 46 regions. By using estimated 24-h urinary iodine excretion (UIE), the prevalence of SAC exceeding the upper tolerable limit of iodine for Japanese children was from 5.2 to 13.7%. The UIC values did not change with age, BSA and BMI percentile, while the Cr concentration simultaneously increased suggesting the effect of urinary creatinine on UI/Cr and estimated 24-h UIE values. Conclusions The iodine intake of Japanese people is adequate, but in some areas it is excessive. The incidence and prevalence of thyroid disorders associated with iodine intake should be obtained especially in the areas where high amounts of iodine are consumed.

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Abstract P359: Assessment of Household Salt Types, Iodine Intake, and Iodine Status in 2019-2020 NHANES

Circulation ◽

10.1161/circ.141.suppl_1.p359 ◽

2020 ◽

Vol 141 (Suppl_1) ◽

Author(s):

Abby G Ershow ◽

Jaime Gahche ◽

Nancy Potischman ◽

Judith Spungen ◽

Pamela Pehrsson

Keyword(s):

At Risk ◽

Dietary Supplements ◽

Age Groups ◽

Urinary Iodine ◽

Iodine Content ◽

Iodine Intake ◽

Iodized Salt ◽

Urinary Iodine Concentration ◽

Iodine Status ◽

The U.S

Background: Iodine is an essential nutrient required for normal thyroid function in all age groups as well as healthy fetal, infant, and child development and growth. Because iodine levels in most foods are low, iodine usually must be provided through dietary supplements or fortified foods (such as salt). In recent NHANES cycles, sub-optimal iodine status has been observed in some U.S. populations, most notably pregnant women. Recent health campaigns have emphasized consuming less sodium and have focused on the primary source of the excess sodium in the U.S. diet: commercially prepared foods, most of which are made with non-iodized salt. Also, recent secular trends towards less home cooking and more use of non-iodized table salts may be contributing to relatively low usage of iodized salt, which was estimated in 2014 to comprise only half of retail salt sales. Therefore, for individuals who also limit their home use of salt in food preparation or at the table, an unintended consequence may be a decline in iodine intake. Population-level data thus are needed on the relative contributions of various foods to iodine intake in relation to iodine status markers, to characterize population groups at risk and develop guidance on appropriate dietary and supplementation strategies. Objective: Describe new measures of iodine intake and iodine status added into NHANES 2019-20, which is a nationally representative survey of the U.S. population. Methods: Iodine intake is being assessed through a questionnaire about household salt types (such as iodized salt or sea salt) and measured iodine content of household iodized salt, as well as individual 24-hour dietary recalls and use of iodine containing dietary supplements. This will be the first time NHANES will estimate dietary iodine intake using a newly developed USDA Special Interest Database on Iodine Content of Foods. Biomarkers include a thyroid panel (including thyroglobulin), inhibitors of iodine uptake in the thyroid (e.g., perchlorates), and urinary iodine concentration. Conclusions: The upcoming NHANES cycle will yield novel data on U.S. population coverage of household iodized salt, as well as individual thyroid and iodine status in relation to dietary iodine intake. Groups at risk from increased physiologic need or dietary preferences that limit iodine sources will be identified. A key tool in undertaking this work will be a new food composition database on the iodine content of U.S. foods. Clarification of key sources of iodine in the U.S. diet will be important in developing dietary guidance.

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Mild to Moderate Iodine Deficiency and Inadequate Iodine Intake in Lactating Women in the Inland Area of Norway

Nutrients ◽

10.3390/nu12030630 ◽

2020 ◽

Vol 12 (3) ◽

pp. 630 ◽

Cited By ~ 1

Author(s):

Synne Groufh-Jacobsen ◽

Lise Mette Mosand ◽

Ingvild Oma ◽

Kjersti Sletten Bakken ◽

Beate Stokke Solvik ◽

...

Keyword(s):

Human Milk ◽

Infant Health ◽

Urinary Iodine ◽

Iodine Concentration ◽

Iodine Intake ◽

Public Health Care ◽

Urinary Iodine Concentration ◽

Cross Sectional ◽

Lactating Women ◽

Iodine Status

Breastfed infants are dependent on an adequate supply of iodine in human milk for the production of thyroid hormones, necessary for development of the brain. Despite the importance of iodine for infant health, data on Norwegian lactating women are scarce. We measured iodine intake and evaluated iodine status and iodine knowledge among lactating women. From October to December 2018, 133 mother–infant pairs were recruited in a cross-sectional study through two public health care centers in Lillehammer and Gjøvik. Each of the women provided two human milk specimens, which were pooled, and one urine sample for analysis of iodine concentration. We used 24-h dietary recall and food frequency questionnaire (FFQ) to estimate short-term and habitual iodine intake from food and supplements. The median (P25, P75) human milk iodine concentration (HMIC) was 71 (45, 127) µg/L—of which, 66% had HMIC <100 µg/L. The median (P25, P75) urinary iodine concentration (UIC) was 80 µg/L (52, 141). The mean (± SD) 24-h iodine intake and habitual intake was 78 ± 79 µg/day and 75 ± 73 µg/day, respectively. In conclusion, this study confirms inadequate iodine intake and insufficient iodine status among lactating women in the inland area of Norway and medium knowledge awareness about iodine.

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