Introduction: Iodine deficiency disorder (IDD) is one of the preventable major public health problems in India. It has been always thought that goitre was only found in the Himalayan goitre belt. Recent surveys outside the conventional goitre belt have identified foci of iodine deficiency in other parts of India.
Aim: 1) To assess the prevalence of goitre among school-going children in the age group of 6-15 years. 2) To find out the relationship of goitre prevalence with the salt intake and urinary iodine excretion. 3) To unfold the iodine nutritional status of the study population.
Material and Methods: The study was conducted from January 2005 to July 2006 in school children of 6-15 years of age, attending the 55 schools of Bellur hobli in the southern part of India. The clinical examination of all the 1600 children of the selected schools was done to detect and grade goitre. Urine and salt samples were collected from sub-samples (n = 400) to estimate the urinary iodine excretion level and iodine content in the salt respectively.
Results: The goitre prevalence in the study population was found to be 0.125%. Urinary iodine excretion (UIE) level of ≥ 100 mcg / l was found in 361 children (90.25%) and < 100 mcg/ l in 39 children (9.75%). Estimation of iodine content of the salt samples revealed that 363 (90.75%) consumed adequately iodised salt (> 15ppm) and 37 (9.25%) consumed inadequately iodised salt (< 15ppm).
Conclusion: Bellur Hobli is not an endemic area for goitre and there is no biochemical iodine deficiency in this population due to effective implementation of Universal iodization programme (UIP). It is reasonable to conclude that by achieving the universal iodisation of salt, IDD can be successfully eliminated from the community.
Goitre; Iodine deficiency; Iodised salt; Urinary iodine excretion
To evaluate the difference of iodine nutritional status between rural and urban residents under the universal salt iodisation policy.
A multistage cluster sampling technique was employed in the present cross-sectional study. In total, 3300 rural and 3300 urban households were selected where the investigation was conducted.
A total of 8553 rural and 8909 urban residents participated in this provincial survey.
Primary and secondary outcome measures
Spot urine samples were collected and the iodine concentration in urine was determined by the modified acid-digestion method.
The median urinary iodine concentration of rural residents was 170.1 μg/L, which was higher than that of urban residents with 153.5 μg/L. For school-aged children, middle-aged people and older people, the median urinary iodine concentration of rural residents was 191.2, 160.2 and 154.0 μg/L, respectively, which was higher than that of urban residents with 166.2, 153.8 and 129.5 μg/L, respectively. Risk factors for urinary concentration of rural residents were age (OR=0.99), terrain (OR=0.83), usual intake of pickled products (OR=1.45) and non-iodised salt intake (OR=0.39), while those for urban residents were age (OR=0.99), terrain (OR=0.83), usual intake of aquatic products (OR=1.24) and non-iodised salt intake (OR=0.27) compared with iodised table salt intake.
The median urinary iodine concentration of rural residents was higher than that of urban residents although they were both falls in optimal iodine status as recommended by WHO/UNICEF/International Council for the Control of Iodine Deficiency Disorders. Iodised salt intake is the major factor which influences the iodine nutritional status mostly for rural and urban residents. The ongoing monitoring of population iodine status remains crucially important.
NUTRITION & DIETETICS; PUBLIC HEALTH; EPIDEMIOLOGY
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
Iodine deficiency affects nearly 1.9 billion people worldwide, but it can be prevented by salt iodization. This cross-sectional survey assessed current iodine status, iodized salt coverage and risk factors for goitre among schoolchildren in South Tajikistan.
Ten primary schools in four districts in South Tajikistan were randomly selected. In schoolchildren aged 7 to 11 years, a spot urine sample was collected for measurement of urinary iodine, dried blood spots were collected for measurement of thyroglobulin, and goitre was assessed by palpation. Iodine content of salt samples and local selling points was determined by coloration using rapid test kits and titration method.
Of 623 schoolchildren enrolled, complete data was obtained from 589. The overall median urinary iodine concentration (UIC) was 51.2 μg/L indicating mild-to-moderate iodine deficiency. Among all children, 46.6% (95% Confidence Interval (CI) = 42.4%-50.6%) of children were found to be goitrous (grade 1 goitre: 30.6%, 95% CI = 26.9%-34.5%; grade 2 goitre: 16.0%, 95% CI = 13.1%-19.2%). The risk factor for goitre remaining significant in the multivariable logistic regression model was 'buying salt once a month’ (OR = 2.89, 95% CI = 1.01-8.22) and 'buying salt once every six months’ (OR = 2.26, 95% CI = 1.01-5.04) compared to 'buying salt every one or two weeks’. The overall median thyroglobulin concentration was elevated at 13.9 μg/L. Of the salt samples from households and selling points, one third were adequately iodised, one third insufficiently and one third were not iodised.
Iodine deficiency remains a serious health issue among children in southern Tajikistan. There is a persisting high prevalence of goitre, elevated thyroglobulin and low UIC despite interventions implemented by Tajikistan and international partners. Quality control of salt iodine content needs to be improved. Continued efforts to raise awareness of the health effects of iodine deficiency are needed to increase consumer demand for iodised salt.
Iodine status; Goitre; Risk factors for goitre; Urinary iodine concentration; Thyroglobulin concentration; Salt iodization; Schoolchildren; Tajikistan
Background: Pregnancy is accompanied by profound alterations in the thyroid economy and the relative iodine deficiency. The median Urinary Iodine Excretion (UIE) is the most reliable indicator of the population’s iodine nutrition. The physiological alterations in normal pregnancy, such as an increased glomerular filtration rate, potentially invalidate UIE as an assessment tool in pregnancy.
Objectives: To assess the Urinary Iodine Excretion (UIE) in pregnant mothers and to enquire about the current status of their iodised salt intake.
Methods: We carried out a cross-sectional study in which urine samples were collected from 45 pregnant mothers who were admitted to the antenatal ward. The iodine level in the urine was analysed by a method which was provided by Singh and Ali, to determine the Urinary Iodine Excretion (UIE). A questionnaire was introduced to document the status of the dietary intake of iodised salt. The UIE was expressed in median (interquartile) and the other data are expressed in frequency and percentage. Fisher Exact test was applied to compare between UIE and iodine intake.
Results: Thirteen (28.88%) pregnant mothers had UIEs of <150 μg/L, which were below the cut-off point of the UIE for pregnant mothers. Overall, 33 mothers were from the Terai region; among them, one third had UIEs of <150 μg/L. Among the 45 pregnant women, 15 (33.34%) were not using iodised salt and the rest were using iodised salt. Among those who were using iodised salt (30 out of 45), 8 pregnant women had UIEs of <150 μg/L and among those who were not using iodised salt, 5 pregnant women had UIEs of < 150 μg/L.
Conclusion: The UIE was below 150μg/L in a substantial percentage (28.89%) of pregnant women of the Terai region, regardless of their intake of iodised salt.
Iodine deficiency disorder; Urinary iodine excretion; Pregnancy
Background: In the United Kingdom, sodium reduction targets have been set for a large number of processed food categories. Assessment and monitoring are essential to evaluate progress.
Objectives: Our aim was to determine whether household consumer panel food-purchasing data could be used to assess the sodium content of processed foods. Our further objectives were to estimate the mean sodium content of UK foods by category and undertake analyses weighted by food-purchasing volumes.
Design: Data were obtained for 21,108 British households between October 2008 and September 2009. Purchasing data (product description, product weight, annual purchases) and sodium values (mg/100 g) were collated for all food categories known to be major contributors to sodium intake. Unweighted and weighted mean sodium values were calculated.
Results: Data were available for 44,372 food products. The largest contributors to sodium purchases were table salt (23%), processed meat (18%), bread and bakery products (13%), dairy products (12%), and sauces and spreads (11%). More than one-third of sodium purchased (37%) was accounted for by 5 food categories: bacon, bread, milk, cheese, and sauces. For some food groups (bread and bakery, cereals and cereal products, processed meat), purchase-weighted means were 18–35% higher than unweighted means, suggesting that market leaders have higher sodium contents than the category mean.
Conclusion: The targeting of sodium reduction in a small number of food categories and focusing on products sold in the highest volumes could lead to large decreases in sodium available for consumption and therefore to gains in public health.
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.
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.
Reports from populations with an insufficient iodine intake suggest that children of mothers with mild iodine deficiency during pregnancy are at risk for cognitive impairments. However, it is unknown whether, even in iodine-sufficient areas, low levels of iodine intake occur that influence cognitive development in the offspring. This study investigated the association between maternal low urinary iodine concentration (UIC) in pregnancy and children's cognition in a population-based sample from a country with an optimal iodine status (the Netherlands).
Setting and participants
In 1525 mother–child pairs in a Dutch multiethnic birth cohort, we investigated the relation between maternal UIC<150 μg/g creatinine, assessed <18 weeks gestation and children's cognition.
Non-verbal IQ and language comprehension were assessed during a visit to the research centre using Dutch test batteries when the children were 6 years.
In total, 188 (12.3%) pregnant women had UIC<150 μg/g creatinine, with a median UIC equal to 119.3 μg/g creatinine. The median UIC in the group with UIC>150 μg/g creatinine was 322.9 μg/g and in the whole sample 296.5 μg/g creatinine. There was a univariate association between maternal low UIC and children's suboptimum non-verbal IQ (unadjusted OR=1.44, 95% CI 1.02 to 2.02). However, after adjustment for confounders, maternal low UIC was not associated with children's non-verbal IQ (adjusted OR=1.33, 95% CI 0.92 to 1.93). There was no relation between maternal UIC in early pregnancy and children's language comprehension at 6 years.
The lack of a clear association between maternal low UIC and children's cognition probably reflects that low levels of iodine were not frequent and severe enough to affect neurodevelopment. This may result from the Dutch iodine fortification policy, which allows iodised salt to be added to almost all processed food and emphasises the monitoring of iodine intake in the population.
Few data on iodine status in Somalia are available, but it is assumed that deficiency is a public health problem due to the limited access to iodized salt. We aimed to describe the iodine status of the population of Somalia and to investigate possible determinants of iodine status. A national 2-stage, stratified household cluster survey was conducted in 2009 in the Northwest, Northeast, and South Central Zones of Somalia. Urinary iodine concentration (UIC) was determined in samples from women (aged 15–45 y) and children (aged 6–11 y), and examination for visible goiter was performed in the Northwest and South Central strata. A 24-h household food-frequency questionnaire was conducted, and salt samples were tested for iodization. The median UICs for nonpregnant women and children were 329 and 416 μg/L, respectively, indicating excessive iodine intake (>300 μg/L). The prevalence of visible goiter was <4%. The coverage of salt iodization was low, with a national average of 7.7% (95% CI: 3.2%, 17.4%). Spatial analysis revealed localized areas of relatively high and low iodine status. Variations could not be explained by food consumption or salt iodization but were associated with the main source of household drinking water, with consumers of borehole water having a higher UIC (569 vs. 385 μg/L; P < 0.001). Iodine intake in Somalia is among the highest in the world and excessive according to WHO criteria. Further work is required to investigate the geochemistry and safety of groundwater sources in Somalia and the impact on human nutrition and health.
Reducing population salt intake has been identified as a priority intervention to reduce non-communicable diseases. Member States of the World Health Organization have agreed to a global target of a 30% reduction in salt intake by 2025. In countries where most salt consumed is from processed foods, programs to engage the food industry to reduce salt in products are being developed. This paper provides a comprehensive overview of national initiatives to encourage the food industry to reduce salt. A systematic review of the literature was supplemented by key informant questionnaires to inform categorization of the initiatives. Fifty nine food industry salt reduction programs were identified. Thirty eight countries had targets for salt levels in foods and nine countries had introduced legislation for some products. South Africa and Argentina have both introduced legislation limiting salt levels across a broad range of foods. Seventeen countries reported reductions in salt levels in foods—the majority in bread. While these trends represent progress, many countries have yet to initiate work in this area, others are at early stages of implementation and further monitoring is required to assess progress towards achieving the global target.
salt reduction; sodium; food composition; government initiative; international; cardiovascular diseases; food industry; monitoring
OBJECTIVE: To provide updated, evidence-based recommendations concerning the effects of dietary salt intake on the prevention and control of hypertension in adults (except pregnant women). The guidelines are intended for use in clinical practice and public education campaigns. OPTIONS: Restriction of dietary salt intake may be an alternative to antihypertensive medications or may supplement such medications. Other options include other nonpharmacologic treatments for hypertension and no treatment. OUTCOMES: The health outcomes considered were changes in blood pressure and in morbidity and mortality rates. Because of insufficient evidence, no economic outcomes were considered. EVIDENCE: A MEDLINE search was conducted for the period 1966-1996 using the terms hypertension, blood pressure, vascular resistance, sodium chloride, sodium, diet, sodium or sodium chloride dietary, sodium restricted/reducing diet, clinical trials, controlled clinical trial, randomized controlled trial and random allocation. Both trials and review articles were obtained, and other relevant evidence was obtained from the reference lists of the articles identified, from the personal files of the authors and through contacts with experts. The articles were reviewed, classified according to study design and graded according to level of evidence. In addition, a systematic review of all published randomized controlled trials relating to dietary salt intake and hypertension was conducted. VALUES: A high value was placed on the avoidance of cardiovascular morbidity and premature death caused by untreated hypertension. BENEFITS, HARMS AND COSTS: For normotensive people, a marked change in sodium intake is required to achieve a modest reduction in blood pressure (there is a decrease of 1 mm Hg in systolic blood pressure for every 100 mmol decrease in daily sodium intake). For hypertensive patients, the effects of dietary salt restriction are most pronounced if age is greater than 44 years. A decrease of 6.3 mm Hg in systolic blood pressure and 2.2 mm Hg in diastolic blood pressure per 100 mmol decrease in daily sodium intake was observed in people of this age group. For hypertensive patients 44 years of age and younger, the decreases were 2.4 mm Hg for systolic blood pressure and negligible for diastolic blood pressure. A diet in which salt is moderately restricted appears not to be associated with health risks. RECOMMENDATIONS: (1) Restriction of salt intake for the normotensive population is not recommended at present, because of insufficient evidence demonstrating that this would lead to a reduced incidence of hypertension. (2) To avoid excessive intake of salt, people should be counselled to choose foods low in salt (e.g., fresh fruits and vegetables), to avoid foods high in salt (e.g., pre-prepared foods), to refrain from adding salt at the table and minimize the amount of salt used in cooking, and to increase awareness of the salt content of food choices in restaurants. (3) For hypertensive patients, particularly those over the age of 44 years, it is recommended that the intake of dietary sodium be moderately restricted, to a target range of 90-130 mmol per day (which corresponds to 3-7 g of salt per day). (4) The salt consumption of hypertensive patients should be determined by interview. VALIDATION: These recommendations were reviewed by all of the sponsoring organizations and by participants in a satellite symposium of the fourth International Conference on Preventive Cardiology. They have not been clinically tested. SPONSORS: The Canadian Hypertension Society, the Canadian Coalition for High Blood Pressure Prevention and Control, the Laboratory Centre for Disease Control at Health Canada, and the Heart and Stroke Foundation of Canada.
The scientific evidences show that the content, baking methods, and types of bread can make health impacts. Bread, as a major part of Iranian diet, demonstrates a significant potential to be targeted as health promotion subject. Healthy Food for Healthy Communities (HFHC) was a project of Isfahan Healthy Heart Program (IHHP), consisting of a wide variety of strategies, like Healthy Bread (HB) Initiative. The HB Initiative was designed to improve the behaviour of both producers and consumers, mainly aiming at making high-fibre, low-salt bread, eliminating the use of baking soda, providing enough rest time for dough before baking (at least one hour), and enough baking time (at least one minute in oven). A workshop was held for volunteer bakers, and a baker-to-baker training protocol under direct supervision was designed for future volunteers. Cereal Organization was persuaded to provide less refined flour that contained more bran. Health messages in support of new breads were disseminated by media and at bakeries by health professionals. Evaluation of the HB Initiative was done using before-after assessments and population surveys. While HB was baked in 1 (0.01%) bakery at baseline, 402 (41%) bakeries in the intervention area joined the HB Initiative in 2009. Soda was completely eliminated and fibre significantly increased from 4±0.4 g% before study to 12±0.6 g% after the intervention (p<0.001). The preparation and baking times remarkably increased. Wastage of bread decreased from 13±1.8 g% to 2±0.5 g% and was expressed as the most important advantage of this initiative by consumers. People who lived in Isfahan city consumed whole bread 6 times more than those who lived in reference area Arak (p<0.001). The HB Initiative managed to add new breads as a healthy choice that were compatible with local dishes and made a model to solve the long-standing problems of bread. It used various health promotion approaches but was best consistent with Beattie's model.
Bread; Community trial; Health promotion; Nutrition; Iran
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
Despite numerous educational programmes to create awareness about iodized salt and iodine deficiency disorders (IDD), a survey conducted in the Western Region of Ghana in 2007 revealed that the goitre rate stood at 18.8%; and 78.1% of households consumed iodized salt, which is below the goal of the IDD programme in Ghana which aimed at 90% household consumption of iodized salt by the end of 2005 and sustaining the gains by 2011. It was therefore, considered timely to investigate the knowledge levels and the extent of utilization of iodized salt among the people living in Bia District, the District with the lowest intake (77.4%) of iodized salt based on findings of the 2007 survey.
This was a descriptive cross-sectional study. It was conducted among a total of 280 household members, mainly in charge of meal preparation, who were interviewed using a structured interview guide. A combination of cluster and simple random sampling techniques was used to select the respondents from all the seven sub- districts in Bia District.
The study revealed that 75.6% of households in the district consumed iodized salt (including households described as occasional users of iodized salt), and knowledge of iodized salt was quite high, as 72% of the respondents knew that not every salt contained iodine. In addition, 69.3% indicated that an inadequate intake of iodized salt can lead to the development of goitre. Despite the high awareness level, only 64.6% of respondents indicated that they exclusively used iodized salt for cooking. The main reason given by exclusive users of common salt was that the price of iodized salt is a little higher than that of common salt.
Although majority of the respondents are aware of the importance of iodized salt and iodine deficiency disorders, only 64.6% exclusively used iodized salt, suggesting that respondents' high knowledge levels did not necessarily translate into an increase in the number of households who used iodized salt. Existing laws and policies on universal salt iodization and quality assurance of iodized salt from the production stage to the distribution/selling stage should be enforced.
Knowledge; Practices; Iodized salt; Iodine deficiency disorders; Ghana
Pregnant women and infants are exceptionally vulnerable to iodine deficiency. The aims of the present study were to estimate iodine intake, to investigate sources of iodine, to identify predictors of low or suboptimal iodine intake (defined as intakes below 100 μg/day and 150 μg/day) in a large population of pregnant Norwegian women and to evaluate iodine status in a sub-population. Iodine intake was calculated based on a validated Food Frequency Questionnaire in the Norwegian Mother and Child Cohort. The median iodine intake was 141 μg/day from food and 166 μg/day from food and supplements. Use of iodine-containing supplements was reported by 31.6%. The main source of iodine from food was dairy products, contributing 67% and 43% in non-supplement and iodine-supplement users, respectively. Of 61,904 women, 16.1% had iodine intake below 100 μg/day, 42.0% had iodine intake below 150 μg/day and only 21.7% reached the WHO/UNICEF/ICCIDD recommendation of 250 μg/day. Dietary behaviors associated with increased risk of low and suboptimal iodine intake were: no use of iodine-containing supplements and low intake of milk/yogurt, seafood and eggs. The median urinary iodine concentration measured in 119 participants (69 μg/L) confirmed insufficient iodine intake. Public health strategies are needed to improve and secure the iodine status of pregnant women in Norway.
iodine; pregnancy; prospective cohort; food frequency questionnaire; the Norwegian Mother and Child Cohort Study (MoBa)
Iodine Deficiency Disorders (IDD) are one of the biggest worldwide public health problem of today. Their effect is hidden and profoundly affects the quality of human life. Iodine deficiency occurs when the soil is poor in iodine, causing a low concentration in food products and insufficient iodine intake in the population. When iodine requirements are not met, the thyroid may no longer be able to synthesize sufficient amounts of thyroid hormone. The resulting low-level of thyroid hormones in the blood is the principal factor responsible for the series of functional and developmental abnormalities, collectively referred to as IDD. Iodine deficiency is a significant cause of mental developmental problems in children, including implications on reproductive functions and lowering of IQ levels in school-aged children. The consequence of iodine deficiency during pregnancy is impaired synthesis of thyroid hormones by the mother and the foetus. An insufficient supply of thyroid hormones to the developing brain may result in mental retardation. Brain damage and irreversible mental retardation are the most important disorders induced by iodine deficiency. Daily consumption of salt fortified with iodine is a proven effective strategy for prevention of IDD.
Iodine; Cretinism; Mental Retardation
Simple goitre is highly prevalent in New Zealand, and there is considerable incidence of toxic goitre. The ætiology of simple goitre seems fairly well established, and an attempt is being made to apply the data from simple goitre to the problems of toxic goitre.
Endemic goitre is of great antiquity among the Maoris, and has been described among Europeans for about fifty years. It occurs in both men and animals. At five years its incidence is similar in boys and girls, later it decreases in boys but increases greatly in girls. It is often hereditary, and many children are born goitrous. In children it is generally small, but may enlarge and cause pressure, myxœdema and toxicity. Its incidence varies greatly in different districts.
The only cause found consistent with this variation in distribution is lack of iodine in the soil. An inverse ratio has been demonstrated between the iodine content of the soil and the incidence of goitre in school children in thirty-three districts. The iodine content of the soil is reflected in the food raised upon it.
The daily iodine intake was estimated at 35 microgrammes in a non-goitrous, and at 20 microgrammes in a goitrous district.
The amount of iodine involved is infinitesimal, and its intake can be ensured by the use of salt for ordinary consumption, which contains four parts per million of potassium iodide.
Toxic goitre is also frequent: in this connexion, the influence of iodine on the thyroid has been investigated. If starved of iodine the thyroid adapts itself either by increasing its colloid or by a diffuse hyperplasia, both may occur in different parts of the same gland. Simple goitre is the response of the healthy thyroid to iodine deficiency, the responding areas may be diffuse or adenomatous, and degenerations may occur. Such goitres may be treated with iodine, in children re-adjustment to the increased intake is readily made, but in adults long accustomed to a low intake, excess often causes too great hormone production, with toxic symptoms, hence the minimal dose alone is permissible in iodized salt.
Goitre stored with iodine at low pressures may become toxic under stress, and this may be precipitated by iodine. The prevalence of toxic goitre may be partly due to the prescription of iodides in therapeutic doses for common ailments.
Diffuse colloid goitre may subside under physiological iodine, the adenomatous is more prone to toxic symptoms and may go on to secondary Graves' disease or to myxœdema. Diffuse hyperplasia is a possible manifestation of iodine deficiency as primary Graves' disease. Lugol's solution probably allows of a temporary storage in this condition. Iodine has certainly some bearing on the problems of toxic goitre.
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
What is the situation of iodine deficiency disorder (IDD) and salt consumption in Jammu region?
The prevalence of IDD has decreased markedly as a result of medical as well as socio-economic factors.
To assess the magnitude of IDD in Jammu region and also assess the salt consumption patterns in the region.
Primary schools in both urban and rural areas.
Clinical examination of study population for goiter, laboratory assessment of casual urine sample for urinary iodine estimation of I2 content of salt samples collected from sub-samples of study population.
School children in the age group of 6-12 years were selected for study using WHO 30-cluster methodology, urine samples were collected from 15% of selected children and salt samples from 5% of sub-sample.
No ethical issues were involved.
An overall goiter prevalence of 11.98% was observed in the region. Females had a prevalence of 16.1% and males 10.1%. The median urinary iodine excretion in the region was 96.5 μg/l (range: 29.0-190.0 μg/l). Forty-nine percent of subjects had biochemical iodine deficiency with 6.7% having moderate and 42.53% mild iodine deficiency. In Jammu region, 74.47% of households consume powdered salt with 98.17% powdered salt samples having an I2 content of greater than 15 ppm.
Iodine deficiency remains a public health problem in the region, though the region seems to be in a state of nutritional transition from iodine deficiency to iodine sufficiency.
Crystalline salt; excretion; goiter; powdered salt; prevalence; urinary iodine
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
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
Public health campaigns in several countries encourage population-wide reduced sodium (salt) intake, but excessive intake remains a major problem. Excessive sodium intake is independently related to adverse blood pressure and is a key factor in the epidemic of prehypertension/ hypertension. Identification of food sources of sodium in modern diets is critical to effective reduction of sodium intake worldwide. We used data from the INTERMAP Study to define major food sources of sodium in diverse East Asian and Western population samples. INTERMAP is an international, cross-sectional, epidemiologic study of 4, 680 individuals ages 40 to 59 years from Japan (four samples), People’s Republic of China (three rural samples), the United Kingdom (two samples), and the United States (eight samples); four in-depth, multipass 24-hour dietary recalls/person were used to identify foods accounting for most dietary sodium intake. In the People’s Republic of China sample, most (76%) dietary sodium was from salt added in home cooking, about 50% less in southern than northern samples. In Japan, most (63%) dietary sodium came from soy sauce (20%), commercially processed fish/seafood (15%), salted soups (15%), and preserved vegetables (13%). Processed foods, including breads/cereals/grains, contributed heavily to sodium intake in the United Kingdom (95%) and the United States (for methodological reasons, underestimated at 71%). To prevent and control prehypertension/hypertension and improve health, efforts to remove excess sodium from diets in rural China should focus on reducing salt in home cooking. To avoid excess sodium intake in Japan, the United Kingdom, and the United States, salt must be reduced in commercially processed foods.
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
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)