Nutritional status of iodine in children: When appropriateness relies on milk consumption and not adequate coverage of iodized salt in households

Spatial-Temporal Analysis of Factors Influencing the Median Urine Iodine Concentration of 8-10-year-old Children in Xinjiang, China 25 Years after Implementation of the Salt Iodization Policy

The iodine status of children has improved and stabilized since China implemented salt iodization measures 25 years ago, but routine monitoring of iodine cannot reflect regional factors that influence the iodine level in children. Therefore, we conducted a regional spatial-temporal analysis of children's median urinary iodine concentration (MUIC) and searched for possible factors that might affect children's iodine levels by mining monitoring data. We analyzed data from Xinjiang collected as part of the "Iodine Deficiency Disease National Monitoring Program" from 2017 to 2020. The study population consisted of 76,268 children who participated in the study. We used global autocorrelation analysis to determine whether the MUIC of children was spatially clustered, local autocorrelation analysis to identify specific clustering areas, local cold and hot spot analysis to verify the reliability of the local autocorrelation results, and a spatial lag model to identify factors affecting the children's MUIC. The MUIC values were 217.70, 227.00, 230.67, and 230.67 µg/L in 2017, 2018, 2019, and 2020, respectively. Global autocorrelation analysis showed that the MUIC of all children in the study was significantly related to region (Z scores all > 1.96, P values all < 0.05) from 2017 to 2020. Partial auto-correlation analysis showed that counties with clusters of high values were mostly concentrated in the southwestern region of Xinjiang, whereas counties with clusters of low values were located in the northern part of Xinjiang. Partial cold spot and hot spot analysis showed the same trend, and there are more overlapping districts and counties in 4 years. Three-dimensional trend analysis indicated that children from the western part of Xinjiang had high levels of urinary iodine. According to spatial lag model, urine iodine concentration level is positively correlated with thyroid volume, average salary, and urbanization rate classification. The MUIC of 8-10-year-old children in Xinjiang was spatially clustered and related to geographic region. Our results show that spatial analysis of survey data combined with geographic technology and public health data can accurately identify areas with abnormal iodine concentrations in children. Additionally, understanding the factors that influence iodine levels in the human population is conducive to improving monitoring methods.

Sodium, Potassium and Iodine Intake in an Adult Population of Lithuania

Hypertension is a leading risk factor for cardiovascular events and death. A reduction in salt intake is among the most cost-effective strategies to reduce blood pressure and the risk of cardiovascular diseases. Increasing potassium lowers blood pressure and is associated with lower cardiovascular risk. Adequate iodine intake is important to prevent iodine deficiency disorders. Salt iodization is a key strategy to prevent such deficiency. In Lithuania, no surveys have been performed to directly assess sodium, potassium and iodine consumption. The aim of the present study was to measure sodium, potassium and iodine intake in a randomly selected adult Lithuanian adult population using 24 h urine collections, and to assess knowledge, attitudes and behavior towards salt consumption. Salt and potassium intakes were estimated in 888 randomly selected participants by 24 h urine sodium and potassium excretion and 679 individuals provided suitable 24 h urine samples for the analysis of iodine excretion. Average salt intake was 10.0 (SD 5.3) g/24 h and average potassium intake was 3.3 (SD 1.3) g/24 h. Only 12.5% of participants consumed less than 5 g/24 h of salt. The median value of urinary iodine concentration (UIC) was 95.5 μg/L. Our study showed that average salt intake is twice as high as the maximum level recommended by the World Health Organization while potassium and iodine intakes in Lithuania are below the recommended levels.

Combination of in situ iodization and Haloferax spp. bacteria enrichment in salt crystallization process

Salts that meet the standard quality are enriched with micronutrients, such as potassium iodate, at least 30 ppm. The iodization can be carried out directly in crystallization ponds (in-situ iodization) in salt fields. This paper reports the effectiveness of in-situ iodization technology combined with the enrichment of Halophilic bacteria consortium and Haloferax spp. to produce bio-based NaCl salt. The brine was first crystallized under sunlight exposure for approximately five days with water temperatures of 32-39 °C and an average wind speed of 2.8-6.0 m/s in each pond with a dimension of 20 × 20 m. Following this, the performance of these bacteria was analyzed in terms of the resulting final concentration of KIO3 (ppm), NaCl concentration (v/v), and water content (v/v). Results showed that the treatment with in situ iodization and Haloferax spp. successfully produce better bio-based salt quality in terms of KIO3 level, NaCl purity, and water contents. Moreover, the method did not produce aqueous and solid wastes, unlike in the conventional salt industry. The optimum condition was found at 50 ppm of KIO3 with the addition of Haloferax spp. SEM analysis shows that the treatment using Haloferax spp. resulted in a larger rectangular and harder crystal salt than the controls.

Iodine in household cooking salt no longer plays a crucial role in iodine status of residents in Tianjin, China

PURPOSE

The contribution of household cooking salt to population iodine status is decreasing in China, the applicability of the coverage rate of iodized salt (IS), proportion of adequately iodized salt (AIS), and salt iodine concentration (SIC) of household cooking salt used for iodine status assessment of residents requires further investigation.

METHODS

Through the IDD control project, 16,445 children and 4848 pregnant women were recruited from Tianjin, China and the relationship between the coverage rate of IS, proportion of AIS, SIC, and population iodine status was analyzed. Additionally, through the thyroid health survey project, 856 children with IS or noniodized salt were recruited. The effects of different household cooking salts on individual iodine status and thyroid health were analyzed.

RESULTS

After adjusting for confounding factors, no relationship was found between the coverage rate of IS, proportion of AIS, SIC of household cooking salt, and iodine status of children and pregnant women (all P > 0.05). No differences in levels of thyroid function and structural indicators were found in children with different household cooking salts (all P > 0.05). Additionally, no relationship was found between noniodized salt exposure and goiter, overt hyperthyroidism, overt hypothyroidism, thyroid nodules, antibody single positivity, or subclinical hypothyroidism (all P > 0.05).

CONCLUSION

Iodine in household cooking salt no longer plays a crucial role in iodine status in Tianjin, China. Other indicators must be identified as beneficial supplements for precise iodine status evaluation not only in Tianjin but also in other large cities in China.

Relationship between Thyroid Status during the First Trimester of Pregnancy and Neonatal Well-Being

Iodine is an essential micronutrient for the synthesis of thyroid hormones. The proper functioning of the thyroid axis is essential for the normal development of the nervous system, especially in the first trimester of gestation. The aim of the present study was to analyze the perinatal outcomes, anthropometry, and APGAR test scores of newborns and to relate them to maternal thyroid status. A total of 190 newborns participated in the study. No correlation was found between thyroid stimulating hormone (TSH) and maternal ioduria values in the first trimester of gestation with the weight or length of the newborn, or the APGAR score at one minute after birth. However, we found significant differences between the APGAR scores of children whose mothers had an iodine sufficiency level in the first trimester compared to the children of mothers with iodine deficiency. Similarly, the APGAR scores of children whose mothers had a TSH > 4 have significantly better APGAR scores than the children of mothers with a TSH < 4. Likewise, we found significant differences between the measurements of the newborns depending on whether their mothers smoked. The children of mothers who took iodine supplements or iodized salt obtained the highest APGAR score at one and five minutes after birth. It is essential to focus on recommending adequate consumption of iodine supplements and iodized salt prior to gestation and at least during the first trimester to achieve better fetal well-being.

Food Iodine Content Table compiled from international databases

ABSATRCT In Brazil, there are no data on the iodine content of foods, making it difficult for the population to assess their consumption of iodine. Such information is necessary for public policies aimed at establishing nutritional goals. The objective this article is to construct a table of the iodine content of foods. For the construction of the table, databases from 14 countries were used. The foods used were those listed in the 2008-2009 Household Budget Survey, except those containing added salt, and the doubts about whether or not the food was submitted to any kind of preparation. The compilation of international databases of iodine content resulted in 266 foods, which were grouped into 15 groups. Iodine was also quantified by food group and iodized salt. Data were presented as median, minimum, and maximum. A broad variation in the iodine content of foods was found between countries and inter- and intra-food groups. Those with the highest content were fish and seafood, and dairy products. Regarding salt iodization, these countries followed the recommendation of the World Health Organization, except for Spain, Norway and Turkey. The Food Iodine Content Table can be a useful tool for assessing iodine intake, being important in research on nutritional status, food guidance, and public health programs.

The association of parents' behaviors related to salt with 24 h urinary sodium excretion of their children: A Spanish cross-sectional study

BACKGROUND

Sodium intake is excessive among Spanish children, but the salt use behaviors of parents and children are unknown. This study aims to determine behaviors related to salt intake in both schoolchildren and parents and the relationship between parental behaviors and 24 h urinary sodium excretion (UNa-24h) in children.

SUBJECTS AND METHODS

A convenience sample was taken from a cross-sectional analysis. Parents completed a self-reported questionnaire about their behaviors related to salt, and their responses were compared with the UNa-24h of their own children. The median test was used to identify differences in UNa-24h according to behaviors. Logistic regression was used to assess the relationship between the behaviors of parents and high sodium excretion in the children and the risk of children's use of table salt, adjusting for age, sex, and BMI. Multinomial logistic regression models, adjusted by the covariates, were used to study the children's salt preferences.

RESULTS

A total of 329 schoolchildren from different Spanish provinces were included in the study (mean age: 9.0 ± 1.2 years, 157 girls). The majority of families (parents mean age: 42.0 ± 5.2 years) reported adding salt to food during cooking (92%), and 59% of them never looked at the sodium content on food labels. However, none of these behaviors were related to UNa-24h (p > 0.05). The use of iodized salt (53%), the presence of a salt shaker on the table (6%), and the use of table salt by fathers (57%), mothers (52%) or children (17%) increased the odds (p < 0.05) of children having a higher UNa-24h. Checking sodium content on food labels and the use of table salt by the children or father was associated with a lower preference for salty foods (p < 0.05).

CONCLUSIONS

It is important to make parents aware of the relationship between their behaviors regarding the use of discretionary salt and their children's sodium intake. Our data suggest that salt-specific education programs on how to reduce salt both in-home and outside the home should be implemented to improve behavior skills related to salt consumption in parents and children.