Search Results (13)

Iodine and fluorine, as halogen elements, are often coexisting in water environments, with nearly 200 million people suffering from fluorosis globally, and, in 11 countries and territories, adolescents have iodine intakes higher than that required for the prevention of iodine deficiency disorders. It has been suggested that excess iodine and/or fluorine can affect thyroid health and intellectual development, especially in children, but their combined effect has been less studied in this population. This study investigated 399 school-age children in Tianjin, China, collected drinking water samples from areas where the school-age children lived, and grouped the respondents according to iodine and fluorine levels. Thyroid health was measured using thyroid hormone levels, thyroid volume, and the presence of thyroid nodules; intelligence quotient (IQ) was assessed using the Raven’s Progressive Matrices (CRT) test; and monoamine neurotransmitter levels were used to explore the potential relationship between thyroid health and intelligence. Multiple linear regression and restricted cubic spline (RCS) analyses showed that iodine and fluorine were positively correlated with thyroid volume and the incidence of thyroid nodules in school-age children, and negatively correlated with IQ; similar results were obtained in the secondary subgroups based on urinary iodine and urinary fluoride levels. Interaction analyses revealed a synergistic effect of iodine and fluorine. A pathway analysis showed that iodine and fluorine were negatively associated with the secretion of free triiodothyronine (FT3) and free tetraiodothyronine (FT4), which in turn were negatively associated with the secretion of thyroid-stimulating hormone (TSH). Iodine and fluorine may affect IQ in school-aged children through the above pathways that affect thyroid hormone secretion; of these, FT3 and TSH were negatively correlated with IQ, whereas FT4 was positively correlated with IQ. The relationship between thyroid hormones and monoamine neurotransmitters may involve the hypothalamic–pituitary–thyroid axis, with FT4 hormone concentrations positively correlating with dopamine (DA), norepinephrine (NE), and 5-hydroxytryptophan (5-HT) concentrations, and FT3 hormone concentrations positively correlating with DA concentrations. Monoamine neurotransmitters may play a mediating role in the effects of iodine and fluoride on intelligence in schoolchildren. However, this study has some limitations, as the data were derived from a cross-sectional study in Tianjin, China, and no attention was paid to the reciprocal effects of iodine and fluorine at different doses on thyroid health and intelligence in schoolchildren in other regions. Full article

Iodine deficiency, the most common cause of preventable mental impairment worldwide, has been linked to poorer intellectual function in several studies. However, to our knowledge, no studies have been performed in moderate iodine-deficient schoolchildren using the complete form of Wechsler Intelligence Scale for Children (WISC-III; Portuguese version). The main purpose of this study was to ascertain whether moderate iodine deficiency would affect the cognitive function of schoolchildren (7–11 years old; 3rd and 4th grades). Raven’s Colored Progressive Matrices (CPM; Portuguese version) were used for measuring the intelligence quotient (IQ) of the total population (n = 256; median UIC = 66.2 μg/L), and the WISC-III was used to study two selected subgroups: one moderately iodine-deficient (n = 30) and the other with adequate iodine intake (n = 30). WISC-III was shown to be the prime instrument for cognitive function assessment among moderate iodine-deficient schoolchildren; this subgroup had a Full-Scale IQ 15.13 points lower than the adequate iodine intake subgroup, with a magnitude effect of d = 0.7 (p = 0.013). Significant differences were also registered in 6 of the 13 Verbal-Performance IQ subtests. Moderate iodine deficiency has a substantial impact on mental development and cognitive functioning of schoolchildren, with significant impairment in both Performance IQ and Verbal IQ spectrum, adversely impacting their educational performance. Full article

According to the Iodine Global Network, Mexico is considered a country with adequate national iodine intake (297 mg/L), but some regions have not been studied. We aimed to evaluate urinary iodine concentration (UIC) and its association with thyroid stimulating hormone (TSH) levels and the nutritional status in 307 children (aged 5 to 11 years) from three elementary schools of Monterrey, northern Mexico. UIC in spot urine samples and capillary TSH levels were measured to assess thyroid function, in addition to weight, height, body mass index (BMI), and waist circumference (WC). We found a median UIC of 442 mg/L and a significant association between UIC and TSH levels by logistic regression when data were adjusted for (1) age and sex; (2) age, sex, and WC; and (3) age, sex, and weight status. UIC values were higher in 7-year-old children compared to 11-year-old children. High prevalences of overweight/obesity (41%) and WC >90 pctl (22%) were observed. This study identified higher UIC levels in children than those previously reported in the country. The UIC showed a positive and significant correlation between TSH levels in the three models evaluated. More studies are needed to assess the causes and possible outcomes of high UIC levels. Full article

This study assesses the status of iodine deficiency among at risk-children and adolescents living in migrant settlements in the Kyrgyz Republic. Children aged 7–15 years from two regional primary schools in the new settlement regions were screened for cognitive and behavioural signs of iodine deficiency using questionnaires. The functional state of the thyroid gland was assessed using ultrasonography and blood tests. Out of 1058 schoolchildren, 15.8% showed signs of iodine deficiency. Female children aged 10–12 years showed a higher prevalence of iodine deficiency. The families of schoolchildren reported limited use of seafood and iodised salt. Children in the migrant regions were at risk of iodine deficiency disorder. Among children, clinical manifestations of iodine deficiency were observed as negative hormonal levels or the presence of goitre. Further investigation on standardised screening instruments for iodine deficiency and the relationship among multilevel analyses are warranted. Full article

Food fortification programs have been conducted in several countries to overcome micronutrient deficiency and related problems with various degrees of effectiveness. Available information regarding the success of food fortification programs in some developing countries, including Indonesia, is still limited. Thus, this study conducts a systematic review of the effects of food fortification of mothers and children using biochemical and anthropometric measures focusing on linear growth. Three databases were used in the literature search, namely PubMed, Science Direct and Google Scholar. Fifteen articles were included for analysis from 517 studies found consisting of Indonesian and English articles published from 2000 to June 2020. Fortification of iron, vitamin A, and iodine can increase the level of hemoglobin, serum ferritin, and serum retinol and median urine iodine excretion, especially in toddlers and schoolchildren. However, multinutrient fortification interventions were associated with various effects on hemoglobin, serum ferritin, and serum retinol but a positive association was found with linear growth indicators in the form of body length for age. The effectiveness of food fortification in reducing the prevalence of stunting still needs more and stronger evidence through studies with large sample size and longer duration. Full article

Universal salt iodisation (USI) was introduced in Sri Lanka in 1995. Since then, four national iodine surveys have assessed the iodine nutrition status of the population. We retrospectively reviewed median urine iodine concentration (mUIC) and goitre prevalence in 16,910 schoolchildren (6–12 years) in all nine provinces of Sri Lanka, the mUIC of pregnant women, drinking-water iodine level, and the percentage of households consuming adequately (15 mg/kg) iodised salt (household salt iodine, HHIS). The mUIC of schoolchildren increased from 145.3 µg/L (interquartile range (IQR) = 84.6–240.4) in 2000 to 232.5 µg/L (IQR = 159.3–315.8) in 2016, but stayed within recommended levels. Some regional variability in mUIC was observed (178.8 and 297.3 µg/L in 2016). There was positive association between mUIC in schoolchildren and water iodine concentration. Goitre prevalence to palpation was a significantly reduced from 18.6% to 2.1% (p < 0.05). In pregnant women, median UIC increased in each trimester (102.3 (61.7–147.1); 217.5 (115.6–313.0); 273.1 (228.9–337.6) µg/L (p = 0.000)). We conclude that the introduction and maintenance of a continuous and consistent USI programme has been a success in Sri Lanka. In order to sustain the programme, it is important to retain monitoring of iodine status while tracking salt-consumption patterns to adjust the recommended iodine content of edible salt. Full article

Salt iodization is the main public health policy to prevent and control iodine deficiency disorders. The National Salt Iodization Impact Assessment Survey (PNAISAL) was conducted to measure iodine concentration among Brazilian schoolchildren. A survey including 6–14-year-old schoolchildren from public and private schools from all 26 Brazilian states and the Federal District was carried out in the biennia 2008–2009 and 2013–2014. Municipalities, schools, and students were randomly selected. Students were interviewed at school using a standard questionnaire, which included the collection of demographic, educational, weight, height, and 10 mL non-fasting urine collection information. The analyses were weighted according to the population of students per federative unit. The median urinary iodine concentration (MUIC) for the entire sample by region, federative unit per school, and student characteristics, was described from the cutoff points defined by the World Health Organization (severe disability: <20 µg/L, moderate: 20–49 µg/L, mild: 50–99 µg/L, adequate: 100–199 µg/L, more than adequate: 200–299 µg/L, and excessive: >300 µg/L). In total, 18,864 students (95.9% of the total) from 818 schools in 477 municipalities from all federative units were included in this study. Almost 70% were brown skin color, nine-years-old or older, studied in urban schools, and were enrolled in elementary school. The prevalence of overweight/obesity, as measured by body mass index (BMI) for age, was about twice as high compared to nutritional deficits (17.3% versus 9.6%). The MUIC arrived at 276.7 µg/L (25th percentile = 175.5 µg/L and 75th percentile = 399.71 µg/L). In Brazil as a whole, the prevalence of mild, moderate, and severe deficit was 6.9%, 2.6%, and 0.6%, respectively. About one-fifth of the students (20.7%) had adequate iodine concentration, while 24.9% and 44.2% had more than adequate or excessive concentration, respectively. The prevalence of iodine deficits was significantly higher among younger female students from municipal public schools living in rural areas with the lowest BMI. The median urine iodine concentration showed that Brazilian students have an adequate nutritional intake, with a significant proportion of them evidencing overconsumption of this micronutrient. Full article

This study evaluates the effect of a topical intervention comprising of fissure sealant, povidone-iodine, and fluoride varnish in preventing caries on occlusal, approximal, and smooth surfaces. This three-year clinical trial was conducted in a remote Indigenous community of Australia. All schoolchildren (age range: 4–17) were invited to participate; those with parental consents to receive three-annual epidemiological examinations and interventions constituted the experimental group, while those with consents for only the epidemiological examination formed a comparison group. The intervention group received an annual application of fissure sealant, povidone–iodine and fluoride varnish for two consecutive years along with the restoration of any cavitated lesions, while the comparison group did not receive any intervention except for the usual care that included emergency treatment and restorations. Incipient and advanced caries were recorded in the permanent dentition while data on confounding variables were collected through questionnaires. Caries increment and progression were the outcome variables. A total of 408 children participated in the baseline examination, 208 finished the study. After adjusting for confounders, the prevented fraction (PF) on occlusal surfaces for advanced caries in the experimental group was 76.1% (mean difference- −0.35, 95% CI: −0.67–0.04), while the PF for progression from incipient to advanced caries was 100%(mean difference- −0.30, 95% CI: −0.52–0.09). The mean number of smooth surfaces that progressed from incipient to advanced caries in the comparison group was more than twice that of the experimental group, the mean difference was −0.25 (95% CI: −0.46–−0.03) with a PF of 61%. The intervention was only effective in preventing advanced caries on occlusal surfaces and in halting the progression of caries on occlusal and smooth surfaces but not on approximal caries. Full article

The inhabitants of Lazio, similarly to those of other Italian regions, have been historically exposed to the detrimental effects of an inadequate intake of iodine. The latter is a micronutrient essential for the biosynthesis of thyroid hormones (TH). Iodine deficiency is responsible for a number of adverse effects on human health known as iodine deficiency disorders (IDD), the most common of which worldwide are goiter and hypothyroidism. In order to reduce IDD, a national salt iodination program was started in Italy in 2005. In this article we reviewed the available data regarding iodine intake in the Lazio population before and after the introduction of the national salt iodination program, in order to evaluate its efficacy and the eventual problem(s) limiting its success. On the whole, the information acquired indicates that, following the introduction of the program, the dietary iodine intake in the Lazio population is improved. There is, however, still much work ahead to ameliorate the iodine prophylaxis in this region. In fact, although a generally adequate iodine intake in school-age children has been observed, there are still areas where a mild iodine insufficiency is present. Moreover, two independent epidemiological surveys on pregnant women evidenced a low urinary iodine concentration with respect to the reference range conceived by the World Health Organization. These findings demonstrate the need for greater attention to the iodine prophylaxis by health care providers (i.e., obstetricians, gynecologists, pediatricians, etc.), and the implementation of effective advertising campaigns aimed at increasing the knowledge and awareness of the favorable effects of iodine supplementation on population health. Full article

Mandatory fortification of bread with iodized salt was introduced in Australia in 2009, and studies using spot urine collections conducted post fortification indicate that Australian schoolchildren are now replete. However an accurate estimate of daily iodine intake utilizing 24-h urinary iodine excretion (UIE μg/day) has not been reported and compared to the estimated average requirement (EAR). This study aimed to assess daily total iodine intake and status of a sample of primary schoolchildren using 24-h urine samples. Victorian primary school children provided 24-h urine samples between 2011 and 2013, from which urinary iodine concentration (UIC, μg/L) and total iodine excretion (UIE, μg/day) as an estimate of intake was determined. Valid 24-h urine samples were provided by 650 children, mean (SD) age 9.3 (1.8) years (n = 359 boys). The mean UIE of 4–8 and 9–13 year olds was 94 (48) and 111 (57) μg/24-h, respectively, with 29% and 26% having a UIE below the age-specific EAR. The median (IQR) UIC was 124 (83,172) μg/L, with 36% of participants having a UIC < 100 μg/L. This convenience sample of Victorian schoolchildren were found to be iodine replete, based on UIC and estimated iodine intakes derived from 24-h urine collections, confirming the findings of the Australian Health Survey. Full article

The aim of our study was to assess nutritional intake and anthropometric statuses in schoolchildren to subsequently determine nutritional adequacy with Spanish Dietary Reference Intake (DRIs). The ANIVA study, a descriptive cross-sectional study, was conducted in 710 schoolchildren (6–9 years) in 2013–2014 in Valencia (Spain). Children’s dietary intake was measured using 3-day food records, completed by parents. Anthropometric measures (weight and height) were measured according to international standards, and BMI-for-age was calculated and converted into z-scores by WHO-Anthro for age and sex. Nutrient adequacy was assessed using DRI based on estimated average requirement (EAR) or adequate intake (AI). Pearson’s chi-square and Student’s t-test were employed. Of our study group (47.61% boys, 52.39% girls), 53.1% were normoweight and the weight of 46.9% was inadequate; of these, 38.6% had excess body weight (19.6% overweight and 19.0% obesity). We found intakes were lower for biotin, fiber, fluoride, vitamin D (p < 0.016), zinc, iodine, vitamin E, folic acid, calcium and iron (p < 0.017), and higher for lipids, proteins and cholesterol. Our results identify better nutritional adequacy to Spanish recommendations in overweight children. Our findings suggest that nutritional intervention and educational strategies are needed to promote healthy eating in these children and nutritional adequacies. Full article

Background and objective: A nationwide survey of schoolchildren was conducted to detect regional differences in urinary iodine excretion in Latvia and to compare the results with data from the newborn thyroid-stimulating hormone (TSH) screening database as well with the results of a similar study performed in Latvia 10 years ago.
Materials and methods: We conducted a cross-sectional school-based cluster survey of 915 children aged 9–12 years in 46 randomly selected schools in all regions of Latvia. Urine samples, questionnaires on the consumption of iodized salt and information on socioeconomic status were collected. TSH levels in newborns were also measured.
Results: The median creatinine-standardized urinary iodine concentration (UIC) in our study was 107.3 mg/g Cr. UIC measurements indicative of mild iodine deficiency were present in 31.6%, moderate deficiency in 11.9% and severe deficiency in 2.8% of the participants. The prevalence of iodine deficiency was the highest in the southeastern region of Latgale and the northeastern region of Vidzeme. The prevalence of TSH values >5 mIU/L followed a similar pattern. The self-reported prevalence of regular iodized salt consumption was 10.2%. Children from urban schools had a significantly lower UIC than children from rural schools.
Conclusions: Our findings suggest that although the overall median UIC in Latvian schoolchildren falls within the lower normal range, almost 50% of the schoolchildren are iodine deficient, especially in urban schools and in the eastern part of Latvia. The absence of a mandatory salt iodization program puts a significant number of children and pregnant women at risk. Full article

A nutrition survey was carried out (food intake registration of three consecutive school days) in a randomly selected group of 353 schoolchildren (188 males and 165 females) with normal nutritional status. The average age of the surveyed students was 10.5 years (CI 95%: 10.3–11.7). There were no significant differences between both sexes in mean values for calorie intake (males: 2072.7 ± 261.7 and females: 2060.9 ± 250.6) and intake of macronutrients, minerals and vitamins. Cereals (34%), dairy products (19%) and meats (17%) were responsible for approximately 70% of total calorie intake. Protein accounted for 20.3% of energy intake, carbohydrates for 48.8%, total fat for 30.9%, and saturated fat for 12.6%. Cholesterol intake was excessive and over two-thirds of protein intake was from animal sources. The mean intakes of calcium, iodine and Vitamins A, D and E were below recommended levels. The dietary patterns of the schoolchildren with normal nutritional status differed from the Mediterranean diet. Intakes of meat were too high and dairy products and cereals consumption was relatively limited; while that of vegetables; legumes; fruits and fish were insufficient; leading to excessive protein and fat intake from animal sources and insufficient mineral (calcium and iodine) and Vitamins A; D and E intake. Full article