Iodine deficiency disorders (IDD) constitute the single largest cause of preventable brain damage worldwide. Majority of consequences of IDD are invisible and irreversible but at the same time these are preventable. In India, the entire population is prone to IDD due to deficiency of iodine in the soil of the subcontinent and consequently the food derived from it. To combat the risk of IDD, salt is fortified with iodine. However, an estimated 350 million people do not consume adequately iodized salt and, therefore, are at risk for IDD. Of the 325 districts surveyed in India so far, 263 are IDD-endemic. The current household level iodized salt coverage in India is 91 per cent with 71 per cent households consuming adequately iodized salt. The IDD control goal in India was to reduce the prevalence of IDD below 10 per cent in the entire country by 2012. What is required is a “mission approach” with greater coordination amongst all stakeholders of IDD control efforts in India. Mainstreaming of IDD control in policy making, devising State specific action plans to control IDD, strict implementation of Food Safety and Standards (FSS) Act, 2006, addressing inequities in iodized salt coverage (rural-urban, socio-economic), providing iodized salt in Public Distribution System, strengthening monitoring and evaluation of IDD programme and ensuring sustainability of IDD control activities are essential to achieve sustainable elimination of IDD in India.
India; iodine deficiency disorders; iodized salt; National Iodine Deficiency Disorders Control Programme; sustainable elimination
Iodine Deficiency Disorders (IDD) Control Programme in Sudan adopted salt iodization as the long-term strategy in 1994. In 2000, it was found that less than 1% of households were using adequately-iodized salt. The objectives of this study were to: (i) study the coverage and variation of different geographical regions of Sudan regarding access to and use of iodized salt, (ii) explore the possible factors which influence the use of iodized salt, (iii) develop recommendations to help in the implementation of the Universal Salt Iodization (USI) strategy in Sudan. This paper is based on the Sudan Household Health Survey (SHHS) dataset. A total sample of 24,507 households was surveyed, and 18,786 cooking salt samples were tested for iodine levels with rapid salt-testing kits. Nationally, the percentage of households using adequately-iodized salt increased from less than 1% in 2000 to 14.4%, with wide variations between states. Access to iodized salt ranged from 96.9% in Central Equatoria to 0.4% in Gezira state. Population coverage with iodized salt in Sudan remains very low. The awareness and political support for USI programme is very weak. National legislation banning the sale of non-iodized salt does not exist. Utilization of the already-existing laws, like the National Standardization and Metrology Law (2008), to develop a compulsory national salt specification, will accelerate the USI in Sudan.
Iodine deficiency disorders; Salt legislations; Universal Salt Iodization; Sudan
For sustainable elimination of iodine deficiency disorders (IDD), it is necessary to consume adequately iodized salt on a regular basis and optimal iodine nutrition can be achieved through universal salt iodization.
To assess the extent of use of adequately iodized salt in the urban slums of Cuttack.
Materials and Methods:
Using a stratified random multi-stage cluster sampling design, a cross-sectional study involving 336 households and 33 retail shops selected randomly from 11 slums of Cuttack was conducted in 2005. A predesigned pretested schedule was used to obtain relevant information and salt iodine was estimated qualitatively by using a spot testing kit and quantitatively using the iodometric titration method.
Proportion, Chi-square test.
Only 60.1% of the households in urban slums of Cuttack were using adequately iodized salt i.e., the iodine level in the salt was ≥15 ppm. Iodine deficiency was significantly marked in sample salts collected from katcha houses as compared with salts collected from pucca houses. Households with low financial status were using noniodized/inadequately-iodized salt. Both crystalline and refined salts were sold at all retail shops. Crystalline salts collected from all retailers had an iodine content < 15 ppm and refined salts collected from one retailer had iodine content < 15 ppm. About 48.5% of salt samples collected from retail shops were adequately iodized.
In the urban slums of Cuttack, retailers were selling crystalline salts, which were inadequately iodized- this would be a setback in the progress towards eliminating IDD.
Iodized salt; mental retardation; sustainable elimination; urban slum
Iodine deficiency is endemic in West Bengal as evident from earlier studies. This community-based, cross-sectional descriptive study was conducted in North 24 Parganas district during August-November 2005 to assess the consumption of adequately-iodized salt and to ascertain the various factors that influence access to iodized salt. In total, 506 households selected using the multi-stage cluster-sampling technique and all 79 retail shops from where the study households buy salt were surveyed. The iodine content of salt was tested by spot iodine-testing kits. Seventy-three percent of the households consumed salt with adequate iodine content (≥15 ppm). Consumption of adequately-iodized salt was lower among rural residents [prevalence ratio (PR): 0.8, 95% confidence interval (CI) 0.7-0.9], Muslims (PR: 0.8, 95% CI 0.7-0.9), and households with monthly per-capita income of ≤US$ 10 (PR: 0.7, 95% CI 0.6-0.8). Those who heard and were aware of the risk of iodine-deficiency disorders and of the benefit of iodized salt were more likely to use appropriate salt (PR: 1.2, 95% CI 1.1-1.3). Those who were aware of the ban on non-iodized salt were more likely to consume adequately-iodized salt (PR: 1.1, 95% CI 1.01-1.3). The iodine content was higher in salt sold in sealed packets (PR: 2.9, 95% CI 1.8-4.8) and stored on shelves (PR: 1.6, 95% CI 1.3-2.0). Seventy-two percent of the salt samples from the retail shops had the iodine content of ≥15 ppm. The findings indicate that elimination of iodine deficiency will require targeting the vulnerable and poor population.
Community-based studies; Cross-sectional studies; Descriptive studies; Goitre; Iodine; Iodine deficiency; Iodized salt; Socioeconomic factors; India
Iodine deficiency (ID) is the world's single most important preventable cause of brain damage and mental retardation. Iodine deficiency disorders (IDDs) is a public health problem in 130 countries, affecting 13% of the world population. The simplest solution to prevent the IDD is to consume iodized common salt every day. In India, significant progress has been achieved toward elimination of IDD, in the last 30 years. Satisfactory levels of urinary iodine excretion and iodine content of salt have been documented by the research surveys conducted by research scientists. The results indicate that we are progressing toward elimination of IDD. IDD is due to a nutritional deficiency, which is prima-rily that of iodine, in soil and water. IDD is known to re-appear if the IDD Control Program is not sustained. To ensure that the population continues to have intake of adequate amount of iodine, there is a need of i) periodic surveys to assess the magnitude of the IDD with respect to impact of iodized salt (IS) intervention; ii) strengthening the health and nutrition education activities to create demand for IS and iii) development of a monitoring information system (MIS) for ensuring that the adequately IS is available to the beneficiaries.
Goiter; iodine; salt; urinary iodine excretion
Iodine deficiency disorders were prevalent in China until the introduction of universal salt iodization in 1995. Concerns have recently arisen about possible excess iodine intake in this context. To document iodine intake and the contribution from iodized salt in China, we surveyed dietary iodine intake during China’s nationally representative 2007 total diet study (TDS) and during an additional TDS in 4 coastal provinces and Beijing in 2009. Iodine intake was broken down by age and sex in 2009. Mean daily iodine and salt intake and the contribution from different food and beverage groups (and in 2009, individual items) was measured. The iodine in food cooked with iodized and noniodized salt was also assessed. The mean calculated iodine intake of a standard male in China was 425 μg/d in 2007 and 325 μg/d in coastal areas in 2009, well below the upper limit (UL) in all provinces. In 2009, iodine intake was above the UL in only 1–7% of age-sex groups, except among children (18–19%). A concerning number of individuals consumed less than the WHO-recommended daily allowance, including 31.5% of adult women. Salt contributed 63.5% of food iodine, and 24.6% of salt iodine was lost in cooking. Overall salt consumption declined between the surveys. Salt iodization assures iodine nutrition in China where environmental iodine is widely lacking. The risk of iodine excess is low, but planned decreases in salt iodization levels may increase the existing risk of inadequate intake. Regular monitoring of urinary iodine and more research on the impact of excess iodine intake is recommended.
What is the current status of Iodine Deficiency Disorders (IDD) in the state of Jharkhand?
(1) To determine the status of iodine deficiency in the state. (2) To determine the availability and cost of adequately iodized salt at the retail shops. (3) To study the perceptions of the community regarding iodine deficiency, salt and iodized salt.
A cross-sectional community-based survey.
Thirty clusters selected through the probability proportion to size (PPS) sampling in the state of Jharkhand.
Children aged 6-12 years, households, retail shopkeepers and opinion leaders.
Quantitative and qualitative methodology using a pretested questionnaire and focus group discussion used to carry out the community-based survey.
Total goiter rate (TGR) was 0.9%. Median urinary iodine level was 173.2 µg/L. The proportion of individuals with urinary iodine levels less than 100 and 50 µg/L were 26.4% and 10%, respectively. Slightly less than two-thirds (64.2%) of the households were found to be consuming adequately iodized salt as measured by titration (greater than 15 ppm). Iodized salt was available across the state and the cost varied between Re. 1 and Rs. 8 per kilogram. A common belief among the community was that iodized salt is equivalent to refined packet salt that is further equivalent to expensive salt.
The results of the present survey show that the iodine nutrition in the state of Jharkhand is optimal. Considering that the consumption of adequately iodized salt should increase from 64.2% to the goal of more than 90%, sustained efforts are required in this place to consolidate the current coverage of adequately iodized salt and increase it to greater than 90%.
Goiter; iodine deficiency disorders; Jharkhand
Several studies pertaining to current status of Iodine Deficiency Disorder Control Programme in India have revealed goiter prevalence in the range of 1.5–44.5%, mean urinary iodine excretion level ranging from 92.5–160 mcg/L and iodized salt coverage ranging from 37–62.3%. Most of these studies were based on school children. However, very few studies have focused on pregnant women. This population is very sensitive to marginalized iodine deficiency throughout their gestational period.
This 40 cluster cross sectional study was done in Raipur district. Iodine content of salt was estimated by using “Rapid Salt Testing Kits” along with observing salt storage practices, at household and in shops. Pregnant women were interviewed by using semi structured comprehensive questionnaire, which was based on knowledge attitude, and practices about salt use pattern and awareness about IDDCP, UIE level were also estimated.
Prevalence of goiter was 0.17%. Many (41.12%) pregnant women had <15ppm iodine content in the salt sample and 51.58% of women had subnormal iodine uptake. Wrong salt storage practice was observed in 36.3% of households.
There were lacunae in Iodine deficiency control program in Chhattisgarh. Implementation and monitoring of program was weak. Thus for monitoring purpose IDD Cell & IDD Laboratory should be established at district level. This will lead to periodic assessment of Iodine Deficiency Disorders, by monitoring of Iodine intake and all other preventive, promotive as well as curative measures in the state.
Iodine Deficiency Disorder Control Program (IDDCP); Monitoring; Evaluation; Goiter; Universal Salt Iodization (USI); Median Urinary Iodine Excretion (MUIE)
Approximately 2.2 billion (2200 million) of the world population are living in the area with Iodine deficiency (ID), most of them in the developing countries. In IRAN about 2 million are exposed to Iodine deficiency. Most of the complications of ID are not curable, especially brain damage. On the other hand, adding iodine to daily salt is a suitable program for decreasing iodine deficiency. This has been the main aim of IDD National committee since 1986. This study is a before-after preventive trial, and was conducted to determine the effect of iodized salt in preventing the disorders of Iodine deficiency.
This study was a preventive field trial in 2 stages before and after prevention. Since 1995, Iodized salt has been distributed in Tabas in Yazd province. Sample of 2,150 students aged 6-18 years were chosen by stratified cluster random sampling method from 24 schools, 12 schools from rural and 12 from urban areas. Goiter frequency and educational status were determined using WHO criteria and mean scored, respectively.
Prevalence of goiter has decreased from 34 to 25 percent after 10 years (P < 0.001). The prevalence in urban areas has decreased from 35.8 to 23.5 percent and in rural from 35.6 to 28.5 percent (P = 0.02). Prevalence of Goiter has changed from 32.8 to 20 percent and from 39.5 to 31.5 in boys and girls, respectively (P < 0.001). There was a statistically significant relation between educational status and goiter frequency before and after prevention (P = 0.01). There was also a statistically significant relation between educational status in 2 stages, before and after intervention (P < 0.001).
Although, there are some confounding variables, such as: educational resources development, improved educational methods, and enhanced family emphasis on extracurricular education, increased frequency of students in higher education after intervention shows the iodine effects on mental function.
Educational status; goiter; iodine deficiency; prevention
Iodine is essential for good function of the thyroid, and its deficiency is of public-health importance in Ethiopia. Iodization of salt is an effective and sustainable strategy to prevent and control iodine deficiency in large populations. The effectiveness of salt-iodization programmes depends on the conservation of iodine concentration in salt at various stages of the supply-chain. The overall objective of the study was to assess the loss of iodine in salt from production to consumption and to estimate the proportion of adults, especially pregnant women, at risk of dietary iodine insufficiency. A cross-sectional study was conducted during February-April 2007 in northern Ethiopia. Iodine concentrations of salt samples from producers (n=41), retailers (n=7), and consumers (n=32) were determined using iodiometric titration. A risk assessment was conducted for dietary iodine insufficiency among adults, including pregnant women, using a semi-probabilistic approach. The concentration of iodine in the sampled salts decreased by 57% from the production site to the consumers. The assessment of exposure showed that adults in 63% (n=20) of the households, including 90% (n=29) with pregnant women, were at risk of insufficient iodine intake. A monitoring and evaluation system needs to be established to ensure adequate supply of iodine along the distribution chain. Special attention is needed for the retailers and consumers. At these levels, dissemination of information regarding proper storage and handling of iodized salt is necessary to address the reported loss of iodine from salt.
Cross-sectional studies; Iodine; Iodine deficiency; Salt; Ethiopia
Background: Universal salt iodization remains the best strategy for controlling iodine deficiency disorders in Nepal.
Aims: This study was designed to study the salt types and the household salt iodine content of school aged children in the hilly and the plain districts of eastern Nepal.
Material and Methods: This cross-sectional study was carried out on school children of seven randomly chosen schools from four districts, namely, Sunsari, Dhankuta, Sankhuwasabha and Tehrathum of eastern Nepal. The school children were requested to bring two teaspoonfuls (approx. 12-15 g) of the salt which was consumed in their households, in a tightly sealed plastic pouch. The salt types were categorized, and the salt iodine content was estimated by using rapid test kits and iodometric titrations. The association of the salt iodine content of the different districts were tested by using the Chi-square test. The sensitivity, specificity, positive predictive values, and negative predictive values of the rapid test kits were compared with the iodometric titrations.
Results: Our study showed that mean±SD values of the salt iodine content in the four districts, namely, Sunsari, Dhankuta, Sankhuwasabha and Tehrathum were 34.2±17.9, 33.2±14.5, 27.4±15.1 and 48.4±15.6 parts per million (ppm). There were 270 (38.2%) households which consumed crystal salt and 437(61.8%) of the households consumed packet salts.
Conclusions: Our study recommends a regular monitoring of the salt iodization programs in these regions. More families should be made aware of the need to ensure that each individual consumes iodized salt.
Iodine deficiency; Salt iodine content; Nepal
Severe iodine deficiency results in impaired thyroid hormone synthesis and thyroid enlargement. In the United States, adequate iodine intake is a concern for women of childbearing age and pregnant women. Beyond this high risk group iodine deficiency is not considered to be a significant problem. This case report describes a 12-year-old male with severe iodine deficiency disorder (IDD) resulting from restricted dietary intake due to multiple food allergies. We describe iodine replacement for this patient and continued monitoring for iodine sufficiency. Children with multiple food allergies, in particular those with restrictions to iodized salt and seafood, should be considered high risk for severe iodine deficiency.
Normal pregnancy results in a number of important physiological and hormonal changes that alter thyroid function. In pregnancy, the thyroid gland being subjected to physiological stress undergoes several adaptations to maintain sufficient output of thyroid hormones for both mother and fetus. Consequently, pregnant women have been found to be particularly vulnerable to iodine deficiency disorders (IDD), and compromised iodine status during pregnancy has been found to affect the thyroid function and cognition in the neonates.
Two decades after successful universal salt iodization (USI) in the country, there is scarce data on the iodine status of the pregnant women and their neonates. This is more relevant in areas like Kashmir valley part of sub-Himalayan belt, an endemic region for IDD in the past. The objective was to estimate Urinary Iodine status in pregnant women, the most vulnerable population.
Materials and Methods:
We studied thyroid function [free T3 (FT3), T3, free T4 (FT4), T4, thyroid stimulating hormone (TSH)] and urinary iodine excretion (UIE) in the 1st, 2nd, and 3rd trimesters and at early neonatal period in neonates in 81 mother–infant pairs (hypothyroid women on replacement) and compared them with 51 control mother–infant pairs (euthyroid).
Mean age of cases (29.42 + 3.56 years) was comparable to that of controls (29.87 + 3.37 years). The thyroid function evaluation done at baseline revealed the following: FT3 2.92 ± 0.76 versus 3.71 ± 0.54 pg/ml, T3 1.38 ± 0.37 versus 1.70 ± 0.35 ng/dl, FT4 1.22 ± 0.33 versus 1.52 ± 0.21 ng/dl, T4 9.54 ± 2.34 versus 13.55 ± 2.16 μg/dl, and TSH 7.92 ± 2.88 versus 4.14 ± 1.06 μIU/ml in cases versus controls (P > 0.01), respectively. The 2nd to 6th day thyroid function of neonates born to case and control mothers revealed T3 of 1.46 ± 0.44 versus 1.48 ± 0.36 ng/dl, T4 of 12.92 ± 2.57 versus 11.76 ± 1.78 μg/dl, and TSH of 3.64 ± 1.92 versus 3.82 ± 1.45 μIU/ml, respectively.
UIE was similar (139.12 ± 20.75 vs. 143.78 ± 17.65 μg/l; P = 0.8), but TSH values were higher in cases (7.92 ± 2.88) as compared to controls (4.14 ± 1.06). Although UIE gradually declined from 1st trimester to term, it remained in the sufficient range in both cases and controls. Thyroid function and UIE was similar in both case and control neonates.
We conclude that pregnant Kashmiri women and their neonates are iodine sufficient, indicating successful salt iodization in the community. Large community-based studies on thyroid function, autoimmunity, malignancies, etc., are needed to see the long-term impact of iodization.
India; neonates; pregnancy; thyroid function; urinary iodine excretion
OBJECTIVE: To determine how iodine deficiency and endemic goitre disappeared in Britain. DESIGN: Review of surveys of endemic goitre and iodine nutrition. MAIN RESULTS: Endemic goitre was widespread in Britain but has declined, most notably since the 1960's. Its disappearance was probably due to changes in farming practice, especially iodine supplementation in dairy herds which has resulted in iodine contamination of milk and dairy produce. CONCLUSIONS: Although iodization of dairy herds offers an indirect method of counteracting iodine deficiency, it is haphazard and there should be careful and continuous monitoring of iodine intakes in the population.
To determine the population access to salt/iodized salt during and after the armed conflict in south Sudan and to illustrate geographical variations in population consumption of iodized salt in south Sudan after the armed conflict.
The sources of data for the conflict period were the 2004 Toward a Baseline: Best Estimates of Social Indicators for Southern Sudan study report and the 2000 Multiple Indicators Cluster Survey, and for the post-conflict period the 2005 Sudan Household Health Survey (SHHS) data set.
After peace agreement, population access to salt increased by 6.8% (Z = 5.488, P < 0.001) and the consumption of iodized salt increased by 32.9% (Z = 24.668, P < 0.001). More than 73% of families were using iodized salt but geographical differences existed between states.
Peace had positive impact on population access to iodized salt in south Sudan. Public health authorities in south Sudan need to establish quality monitoring and surveillance systems to track progress toward Universal Salt Iodization goal defined by the World Health Organization, United Nations Children’s Fund, and the International Council for the Control of Iodine Deficiency Disorders.
Both insufficient and excess iodine may produce thyroid disease. After salt iodization in China, the median urine iodine concentration (UIC) of children aged 8–10 years appeared adequate. However, it is unknown whether dietary changes due to rapid economic development in Shanghai have affected whole population iodine nutrition.
To assess dietary iodine intake, UIC and the prevalence of thyroid disease in the general population of Shanghai.
A cross-sectional survey was conducted with general participants aged 5–69 years (n = 7,904) plus pregnant and lactating women (n = 380 each) selected by stratified multistage sampling. The iodine concentrations in their salt, drinking water and urine were measured. Daily iodine intake was estimated using the total diet study approach. Serum thyroid hormone concentrations and thyroid-related antibodies were measured and thyroid ultrasonography was performed.
The median iodine concentration in salt was 29.5 mg/kg, and 12.8 µg/L in drinking water. Iodized salt, used by 95.3% of participants, contributed 63.5% of total dietary iodine. Estimated daily iodine intake was 225.96 µg. The median UIC of general participants was 146.7 µg/L; UIC <100 µg/L (iodine insufficiency) was seen in 28.6%; UIC >300 µg/L (iodine excess) in 10.1%. Pregnant women had a median UIC of 135.9 µg/L, with UIC <150 µg/L in 55.4%. Thyroid nodules and subclinical hypothyroidism were found in 27.44% and 9.17%, respectively.
According to published criteria, the current dietary iodine intake in Shanghai was generally sufficient and safe, but insufficient in pregnant women. Thyroid nodules and subclinical hypothyroidism were the commonest thyroid diseases identified.
Iodine deficiency disorder (IDD) creates major public health problems in India, including Gujarat. The Bharuch district is a known iodine deficiency endemic area. This study was conducted to estimate the prevalence of goiter in primary school children; to determine the median urinary iodine concentration; to assess the level of iodine in salt samples at the household and retail shop levels; and to study the profile of salt sold at retail shops.
This study was carried out by using the 30-cluster survey method in the primary schools of the rural areas in Bharuch district. A total of 70 students, including five boys and five girls from the first to seventh classes, who were present in class on the day of the visit were selected randomly for goiter examination from each village. Urine samples were collected from one boy and one girl from each class in each cluster. From each community, a maximum of two boys and two girls from each standard in the same age group were examined and also salt samples were tested from their households. From each village, one retail shop was visited and the salt purchased from those shops was immediately tested for iodine with spot kits.
We found a goiter prevalence of 23.2% (grade 1 – 17.4% and grade 2 – 5.8%). As the age increased, the goiter prevalence decreased except in nine-year-olds. The median urinary iodine excretion level was 110 μg/L. An Iodine level > 15 ppm was found in 93% of the salt samples tested at the household level.
The present study showed moderate goiter prevalence in primary school children in the Bharuch district of Gujarat and an inadequate iodine content of salt at some household levels.
Goitre survey; IDD; prevalence; primary school children; household level
Background & objectives:
Despite years of salt iodization, goitre continues to be a major public health problem worldwide. We examined the prevalence of goitre in the post-iodization phase and the relationship of goitre with micronutrient status and thyroid autoimmunity in school children of Chandigarh, north India.
Two phase study; in the first phase, 2148 children of 6 to 16 yr were screened for goitre by two independent observers as per the WHO grading system. In the second phase, a case-control study, 191 children with goitre and 165 children without goitre were compared with respect to urinary iodine, iodine content of salt, serum levels of T3, T4, TSH, anti-TPO (thyroid peroxidase) antibody, haemoglobin, ferritin and selenium.
Prevalence of goitre in the studied subjects was 15.1 per cent (13.9% in 6 to 12 yr and 17.7% in 13 to 16 yr age group, P= 0.03). Median urinary iodine excretion in both the groups was sufficient and comparable (137 and 130 µg/l). 3.2 per cent children with goitre and 2.4 per cent without goitre had hypothyroidism (subclinical and clinical) and only one child with goitre had subclinical hyperthyroidism. Nine (4.9%) children in the goitre group and 3 (1.9%) in control group had anti-TPO antibody positivity. The median serum selenium levels were not different in both the groups (181.9 and 193.5 µg/l). Seventy one (37.4%) of the goitrous children had anaemia (haemoglobin <12 g/dl) as compared to 41 (24.8%) of the control group (P <0.01). More number of goitrous children (39, 20.6%) were depleted of tissue iron stores (serum ferritin <12 µg/l) as compared to controls (11, 6.4%; P<0.001). Serum ferritin level negatively correlated with the presence of goitre (r = - 0.22, P =0.008) and had an OR of 2.8 (CI 1.20 - 6.37, P =0.017).
Interpretation & conclusions:
There was a high prevalence of goitre in young children despite iodine repletion and low thyroid autoimmunity. The concurrent iron deficiency correlated with the presence of goiter. However, the cause and effect relationship between iron deficiency state and goitre requires further elucidation.
Goitre; iodine deficiency; iron deficiency; selenium; thyroid autoimmunity
In 1997 a currently obligatory model of iodine prophylaxis, based on mandatory iodization of household salt with 30 mg KI/kg, was introduced. The aim of our study was to assess the iodine intake among school-age children living in Opoczno in 3 subsequent time points – in 1994, before establishment of currently operating model of iodine prophylaxis, in 1999 – 2 years after implementation of iodine prophylaxis and in 2010, – 14 years after its implementation.
We assessed goitre incidence and urine iodine concentration (UIC) in 104 children in 1994, 207 children in 1999 and 174 children in 2012. Age of examined children ranged from 6 to 15 years. The thyroid volumes evaluated by ultrasound were compared to reference values for thyroid volume proposed by Zimmermann at al. Moreover, we have introduced a new index – V/BSA ratio (comparison of thyroid volume to the body surface area), which to our belief allows for more accurate assessment of thyroid volume.
The median of UICs was 45.5 μg/L (1994), 101.1 μg/L (1999) and 100.6 μg/L (2010). The distribution of obtained results has changed as well – iodine concentrations below 50 μg/L were present in 59.1% children in 1994, in 12.6% children – in 1999 and in 7.1% children – in 2010.
Although a significant decrease in goitre incidence with regard to age – 92.6% (1994) vs 18.5% (1999) and 15.8% (2010), as well as with regard to BSA – 95.4% (1994) vs 15.2% (1999) and 11.6% (2010) was observed, it still points to the iodine deficiency, which is in contradiction with UICs as they are within normal limits. V/BSA ratio avoids such discrepancy. The values of ratio V/BSA were higher in 1994 (7.079 ± 2.775) than in 1999 (2.935 ± 1.112) (p<0.05) and in 2010 (2.846 ± 1.029) (p<0.05).
Hitherto model of iodine prophylaxis has proved to be effective in eliminating the iodine deficiency. The iodine intake is now more even, homogenous, which translates into smaller scatter of UICs and less percentage of children, in whom UIC is less than 50 μg/L. However, the iodine intake only slightly exceeds the recommended values, so median of UICs oscillates around the lower limit of references values.
Iodine prophylaxis; Goitre; Schoolchildren; Urine iodine concentration
This cross-sectional study investigated the prevalence of goitre in Isfahan, a centrally-located city in Iran, 15 years after the initiation of universal salt iodization. In total, 2,523 Isfahani adults (1,275 males, 1,248 females) aged >20 years were selected by multi-stage cluster-sampling method. Goitre rate, serum thyroid-stimulating hormone (TSH), thyroxine (T4), thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TgAb), and urinary iodine concentration (UIC) were measured and compared between the goitrous (n=478) and the non-goitrous (n=2,045) participants. The total goitre rate was 19% (n=478) of the 2,523 adults. The rate of Grade I and II goitre was 12.4% (n=312) and 6.6% (n=166) respectively. The total goitre rate, Grade I and II goitre were more prevalent among women than among men. Hypothyroidism was observed in 6.4% (130/2,045) and 18.6% (89/478) of the non-goitrous and goitrous participants respectively [odds ratio (OR)=3.6, 95% confidence interval (CI) 2.7-4.9, p=0.001]. Hyperthyroidism was present in 0.8% (17/2,045) and 5.2% (29/478) of the non-goitrous and goitrous adults respectively (OR=9.0, 95% CI 4.9-16.6, p=0.001). Hypothyroidism was more prevalent in Grade II than in Grade I goitre and among those without goitre (31.3%, 14.1%, and 6.4% respectively) (p=0.001). Positive TPOAb was observed in 24% (n=50) of the non-goitrous and 33.5% (n=84) of the goitrous subjects (p=0.03). Positive TPOAb was observed in 24.6% (35 of 142) of the Grade I and 45% (49 of 109) of the Grade II goitrous adults (p=0.001). Positive TgAb was observed in 21.6% (n=45) of the non-goitrous and 35.9% (n=90) of the goitrous adults (p=0.001). Positive TgAb was observed in 30.3% (43 of 142) of the Grade I and 43.1% (47 of 109) of the Grade II goitrous adults (p=0.04). The median UIC was 18 μg/dL (range 1-80 μg/dL). It was 17.9 μg/dL and 19 μg/dL in the non-goitrous and goitrous adults respectively. After 15 years of successful universal salt iodization in Isfahan, goitre is still endemic, which may be due to thyroid autoimmunity. However, other environmental or genetic factors may have a role.
Autoimmunity; Cross-sectional studies; Goitre; Hypothyroidism; Hyperthyroidism; Impact studies; Iodine; Iodine deficiency; Iran
Iodine deficiency is severe public health problem in Ethiopia. Although urinary iodine excretion level (UIE) is a better indicator for IDD the goitre rate is commonly used to mark the public health significance. The range of ill effect of IDD is however beyond goitre in Ethiopia. In this study the prevalence of goitre and its association with reproductive failure, and the knowledge of women on Iodine Deficiency were investigated.
A cross-section community based study was conducted during February to May 2005 in 10998 women in child bearing age of 15 to 49 years. To assess the state of iodine deficiency in Ethiopia, a multistage "Proportional to Population Size" (PPS) sampling methods was used, and WHO/UNICEF/ICCIDD recommended method for goitre classification.
Total goitre prevalence (weighted) was 35.8% (95% CI 34.5–37.1), 24.3% palpable and 11.5% visible goitre. This demonstrates that more than 6 million women were affected by goitre.
Goitre prevalence in four regional states namely Southern Nation Nationalities and People (SNNP), Oromia, Bebshandul-Gumuz and Tigray was greater than 30%, an indication of severe iodine deficiency. In the rest of the regions except Gambella, the IDD situation was mild to moderate. According to WHO/UNICEF/ICCIDD this is a lucid indication that IDD is a major public health problem in Ethiopia. Women with goitre experience more pregnancy failure (X2 = 16.5, p < 0.001; OR = 1.26, 1.12 < OR < 1.41) than non goitrous women. Similarly reproductive failure in high goitre endemic areas was significantly higher (X2 = 67.52; p < 0.001) than in low. More than 90% of child bearing age women didn't know the cause of iodine deficiency and the importance of iodated salt.
Ethiopia is at risk of iodine deficiency disorders. The findings presented in this report emphasis on a sustainable iodine intervention program targeted at population particularly reproductive age women. Nutrition education along with Universal Salt Iodization program and iodized oil capsule distribution in some peripheries where iodine deficiency is severe is urgently required.
Objective: We aim to describe the environment iodine concentration in salt, water and soil along Zhejiang Province coast in the China foreland. It will be helpful for us to judge whether this area is insufficient in iodine and universal iodized salt is necessary or not. Methods: We collected iodized salt samples, drinking water samples (tap water in the towns, and well water or spring water in the villages), water samples from different sources (ditches, lakes, rivers) and soil samples through random sampling in June, 2005. Salt, water and soil iodine was detected by arsenic-cerium redox method. Statistical analysis was expressed as mean±SEM by Windows SPSS 13.0. Results: (1) The iodine concentration in salt was 27.9±4.33 mg/kg (n=108). (2) Seventy-five water samples were collected. The water iodine value was 0.6~84.8 μg/L (mean of 11.66 μg/L). The watershed along the Qiantang River has significantly higher iodine content than the water in Lin’an in mountain area (P<0.01). The iodine content and mean iodine content of tap water, well or spring water and natural water sources were 4.30±2.43 μg/L (n=34), 23.59±27.74 μg/L (n=19) and 12.72±10.72 μg/L (n=22) respectively. This indicated that among environmental water sources, the ditch iodine content was the highest with river water iodine being the lowest (P<0.01). (3) Soil iodine value was 0.11~2.93 mg/kg (mean of 1.32 mg/kg). Though there was no statistical difference of soil iodine in different districts (P=0.131), soil iodine content correlated positively with water iodine content. Conclusion: Iodine concentration in salt accords with national policy of adding iodine in salt. Foreland has more iodine in water than mountain area. The data reflected that water and soil iodine in foreland area was not high, which suggests universal iodized salt should be necessary. Environment iodine has relatively close association with pollution.
Iodine; Salt; Water; Soil; Coast
Mild iodine deficiency during pregnancy can have significant effects on fetal development and future cognitive function. The purpose of this study was to characterise the iodine status of South Australian women during pregnancy and relate it to the use of iodine-containing multivitamins. The impact of fortification of bread with iodized salt was also assessed. Women (n = 196) were recruited prospectively at the beginning of pregnancy and urine collected at 12, 18, 30, 36 weeks gestation and 6 months postpartum. The use of a multivitamin supplement was recorded at each visit. Spot urinary iodine concentrations (UIC) were assessed. Median UICs were within the mildly deficient range in women not taking supplements (<90 μg/L). Among the women taking iodine-containing multivitamins UICs were within WHO recommendations (150–249 μg/L) for sufficiency and showed an increasing trend through gestation. The fortification of bread with iodized salt increased the median UIC from 68 μg/L to 84 μg/L (p = .011) which was still in the deficient range. Pregnant women in this region of Australia were unlikely to reach recommended iodine levels without an iodine supplement, even after the mandatory iodine supplementation of bread was instituted in October 2009.
Iodine; Pregnancy; Urine; Supplements
Iodine deficiency disorders (IDD) are widespread in China. Presently, IDD have been put under control by Universal Salt Iodisation (USI) in China; however, there is a lack of evidence on whether the iodine status in adults, pregnant women and lactating women is optimal. This study was therefore conducted to assess the iodine nutrition and thyroid function of children, adults, pregnant women and lactating women residing in areas where the USI program is fully established.
Six areas were selected according to the geographical regions in China. In each of these areas, we selected 4 distinct groups of subjects (children, adults, pregnant women and lactating women) in regions where the coverage rate of iodised salt was more than 95% and the levels of iodine and fluoride in drinking water were less than or equal to 10 µg/L and 1 mg/L, respectively. We tested the iodine content of salt, urinary iodine (UI), free thyroxin (FT4), thyrotropin (TSH), thyroglobulin (Tg), thyroglobulin antibody (Tg-Ab) and antimicrosomal antibody (TM-Ab) in the 4 groups, and examined the thyroid volume in children.
The median urinary iodine (MUI) concentrations were 271.4 μg/L, 260.2 μg/L, 205.9 μg/L and 193.9 μg/L in children, adults, pregnant women and lactating women, respectively; MUI in children and adults were more than adequate. The goitre prevalence (GP) in children was 6.70%. The odds ratios (OR) of subclinical hypothyroidism in the Tg-Ab- or TM-Ab-positive groups were 3.80, 7.65, 2.01 and 7.47 for children, adults, pregnant women and lactating women, respectively, compared with the negative groups.
The iodine status in children and adults is above the requirement, we should reduce their iodine intake. Subclinical hypothyroidism easily occurs in the Tg-Ab or TM-Ab positive groups.
Iodine is a trace element that is fundamental for human health: its deficiency affects about two billion people worldwide. Fruits and vegetables are usually poor sources of iodine; however, plants can accumulate iodine if it is either present or exogenously administered to the soil. The biofortification of crops with iodine has therefore been proposed as a strategy for improving human nutrition. A greenhouse pot experiment was carried out to evaluate the possibility of biofortifying tomato fruits with iodine. Increasing concentrations of iodine supplied as KI or KIO3 were administered to plants as root treatments and the iodine accumulation in fruits was measured. The influences of the soil organic matter content or the nitrate level in the nutritive solution were analyzed. Finally, yield and qualitative properties of the biofortified tomatoes were considered, as well as the possible influence of fruit storage and processing on the iodine content. Results showed that the use of both the iodized salts induced a significant increase in the fruit’s iodine content in doses that did not affect plant growth and development. The final levels ranged from a few mg up to 10 mg iodine kg -
1 fruit fresh weight and are more than adequate for a biofortification program, since 150 μg iodine per day is the recommended dietary allowance for adults. In general, the iodine treatments scarcely affected fruit appearance and quality, even with the highest concentrations applied. In contrast, the use of KI in plants fertilized with low doses of nitrate induced moderate phytotoxicity symptoms. Organic matter-rich soils improved the plant’s health and production, with only mild reductions in iodine stored in the fruits. Finally, a short period of storage at room temperature or a 30-min boiling treatment did not reduce the iodine content in the fruits, if the peel was maintained. All these results suggest that tomato is a particularly suitable crop for iodine biofortification programs.
biofortification; iodine; iodine deficiency; potassium iodate; potassium iodide; Solanum lycopersicum L.; tomato