1
|
Ursu HI, Toader OD, Podia-Igna C, Delia CE, Firta AR, Tupea CC, Tudor LM, Gheorghiu ML, Suciu N. IODINE STATUS IN PREGNANT WOMEN AFTER A DECADE OF UNIVERSAL SALT IODIZATION IN ROMANIA. ACTA ENDOCRINOLOGICA-BUCHAREST 2016; 12:161-167. [PMID: 31149082 DOI: 10.4183/aeb.2016.161] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Objective To assess iodine status (median urinary iodine concentration) in 118 pregnant women during the third trimester from endemic or non-endemic areas, a decade after implementation of Universal Salt Iodization in Romania. Subjects and methods One hundred and eighteen pregnant women in the third trimester were included in the study group (age range: 16 - 46 years, mean age: 28.78 years). Median urinary iodine concentration (UIC) and body mass index (BMI) were evaluated. Data regarding region of provenance, smoking habits during pregnancy, education level, iodized salt intake, bread intake, iodine supplements, comorbidities (iron deficiency anemia) and birth weight were assessed. Morning urine was collected to measure median UIC. The study was approved by the Local Ethics Committee. Results Median UIC in the study group was 206 mcg/L, reflecting iodine sufficiency during pregnancy. There is a statistically significant difference between pregnant women with and without iodine supplements from rural areas (281.5 versus 196.1 mcg/L, respectively, p=0.023). In the subgroup without iodine supplementation, there was a significant difference between overweight and obese subjects vs. normal weight subjects (232.5 versus 194 mcg/L, p=0.012). Only in the subgroup with a daily intake of less than 5 slices of bread (usually containing iodized salt) we found significant differences between those with and without iodine supplements (245.2 versus 128.3 mcg/L). Iron deficiency anemia was found in 29.66% and 19.49% were current smokers during pregnancy. Conclusions Median UIC in the study group was 206 mcg/L, reflecting iodine sufficiency during pregnancy. The difference between the subgroup with iodine supplements and the subgroup without iodine supplements was not statistically significant, probably due to the excessive consumption of bread and other bakery products which is traditional in Romania.
Collapse
Affiliation(s)
- H I Ursu
- "C. I. Parhon" National Institute of Endocrinology, Bucharest, Romania.,"Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania
| | - O D Toader
- "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania.,"Alfred Rusescu" Institute for Mother and Child, Bucharest, Romania
| | | | - C E Delia
- "Alfred Rusescu" Institute for Mother and Child, Bucharest, Romania
| | - A R Firta
- "Alfred Rusescu" Institute for Mother and Child, Bucharest, Romania
| | - C C Tupea
- "C. I. Parhon" National Institute of Endocrinology, Bucharest, Romania
| | - L M Tudor
- "Alfred Rusescu" Institute for Mother and Child, Bucharest, Romania
| | - M L Gheorghiu
- "C. I. Parhon" National Institute of Endocrinology, Bucharest, Romania.,"Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania
| | - N Suciu
- "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania.,"Alfred Rusescu" Institute for Mother and Child, Bucharest, Romania
| |
Collapse
|
2
|
Rydbeck F, Rahman A, Grandér M, Ekström EC, Vahter M, Kippler M. Maternal urinary iodine concentration up to 1.0 mg/L is positively associated with birth weight, length, and head circumference of male offspring. J Nutr 2014; 144:1438-44. [PMID: 25031330 DOI: 10.3945/jn.114.193029] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Adequate iodine status in early life is crucial for neurodevelopment. However, little is known about the effects of maternal iodine status during pregnancy on fetal growth. The present study investigated the potential impact of maternal iodine status during pregnancy on offspring birth size. This large prospective cohort study was nested in a Bangladeshi population-based randomized supplementation trial in pregnant women [MINIMat (Maternal and Infant Nutrition Interventions in Matlab)]. Urine samples obtained at 8 wk of gestation from 1617 women were analyzed for iodine and other elements, such as arsenic and cadmium, using inductively coupled plasma mass spectrometry. Anthropometric measurements at birth included weight, length, and head and chest circumference. Maternal urinary iodine concentrations (UICs) ranged from 0.020 to 10 mg/L, with a median of 0.30 mg/L. Below ∼1.0 mg/L, UIC was significantly positively associated with birth weight and length. Birth weight and length increased by 9.3 g (95% CI: 2.9, 16) and 0.042 cm (95% CI: 0.0066, 0.076), respectively, for each 0.1-mg/L increase in maternal UIC. No associations were observed between UIC and head or chest circumference. When we stratified the analyses by newborn sex, the positive associations between maternal UIC (<1 mg/L) and measurements of size at birth were restricted to boys, with no evidence in girls. Among boys, the mean weight, length, and head circumference increased by 70 g (P = 0.019), 0.41 cm (P = 0.013), and 0.28 cm (P = 0.031) for every 0.5-mg/L increase in maternal UIC. Maternal iodine status was positively associated with weight, length, and head circumference in boys up to ∼1 mg/L, which is well above the recommended maximum concentration of 0.5 mg/L. The associations leveled off at UIC ≥ 1 mg/L. Our findings support previous conclusions that the advantages of correcting potential iodine deficiency outweigh the risks of excess exposure.
Collapse
Affiliation(s)
- Filip Rydbeck
- Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden
| | - Anisur Rahman
- Centre for Reproductive Health, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh; and
| | - Margaretha Grandér
- Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden
| | - Eva-Charlotte Ekström
- Department of Women's and Children's Health, International Maternal and Child Health, University Hospital, Uppsala, Sweden
| | - Marie Vahter
- Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden
| | - Maria Kippler
- Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden;
| |
Collapse
|
3
|
Fiore E, Tonacchera M, Vitti P. Influence of iodization programmes on the epidemiology of nodular goitre. Best Pract Res Clin Endocrinol Metab 2014; 28:577-88. [PMID: 25047207 DOI: 10.1016/j.beem.2014.04.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Iodine is essential for the synthesis of thyroid hormones. Iodine deficiency can affect human health in different ways, and is commonly referred to as iodine deficiency disorders (IDD). These range from defective development of the central nervous system during the fetal-neonatal life, to goitre in the adult. Only a few countries were completely iodine sufficient before 1990. Since then, a major effort has been made to introduce salt iodization to ensure sufficient intake of iodine in deficient areas. Iodine prophylaxis has been shown to exert a pivotal role in abating goitre and other iodine-deficiency disorders, and has also been shown to modulate the pattern of thyroid diseases. An increased frequency of thyroid autoimmunity and of hypothyroidism has been observed after introducing iodization programmes. Nevertheless, available evidence clearly confirms that the benefits of correcting iodine deficiency, consisting mainly of reducing nodular goitre and non-autoimmune hyperthyroidism, far outweigh the risks of iodine supplementation.
Collapse
Affiliation(s)
- Emilio Fiore
- Department of Clinical and Experimental Medicine, Section of Endocrinology, University of Pisa, Pisa, Italy.
| | - Massimo Tonacchera
- Department of Clinical and Experimental Medicine, Section of Endocrinology, University of Pisa, Pisa, Italy.
| | - Paolo Vitti
- Department of Clinical and Experimental Medicine, Section of Endocrinology, University of Pisa, Pisa, Italy.
| |
Collapse
|
4
|
Aghini Lombardi F, Fiore E, Tonacchera M, Antonangeli L, Rago T, Frigeri M, Provenzale AM, Montanelli L, Grasso L, Pinchera A, Vitti P. The effect of voluntary iodine prophylaxis in a small rural community: the Pescopagano survey 15 years later. J Clin Endocrinol Metab 2013; 98:1031-9. [PMID: 23436921 DOI: 10.1210/jc.2012-2960] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
CONTEXT Iodine deficiency disorders are a major public health problem, and programs have been implemented to improve iodine nutrition. OBJECTIVE The objective of the study was to verify the effects of voluntary iodine prophylaxis in a small rural community (Pescopagano, Italy). DESIGN The design of the study was the evaluation of the prevalence of thyroid disorders 15 years after a previous survey conducted before iodine prophylaxis. SETTING The setting for this study was a general community survey. PARTICIPANTS One thousand one hundred forty-eight residents were examined in 2010 and 1411 in 1995. RESULTS In 2010, 757 of 1148 subjects (65.9%) routinely used iodized salt, urinary iodine excretion being significantly higher than in 1955 (median 98.0 μg/L, vs 55.0 μg/L, P < .0001). The prevalence of goiter was lower in 2010 than in 1995 (25.8% vs 46.1%, P < .0001), mainly due to the reduction of diffuse goiter (10.3% vs 34.0%, P < .0001). In 2010 vs 1995, thyroid autonomy in subjects younger than 45 years old (3 of 579, 0.5% vs 25 of 1010, 2.5% P = .004) and nonautoimmune hyperthyroidism in subjects older than 45 years old (8 of 569, 1.4% vs 18 of 401, 4.5%, P = .03) were less frequent. The prevalence of hypothyroidism was higher in 2010 vs 1995 (5.0% vs 2.8%, P = .005), mainly because of an increased frequency of subclinical hypothyroidism in subjects younger than 15 years old (7 of 83, 8.4% vs 0 of 419, 0.0%, P < .0001). Accordingly, serum thyroid autoantibodies (19.5% vs 12.6%; P < .0001) and Hashimoto's thyroiditis (14.5% vs 3.5%; P < .0001) were more frequent in 2010 than in 1995. CONCLUSIONS In the present work, the role of voluntary iodine prophylaxis was assessed in a small rural community relatively segregated, in which genetic and other environmental factors have not substantially changed between the 2 surveys. Iodine intake strongly affected the pattern of thyroid diseases, but the benefits of correcting iodine deficiency (decreased prevalence of goiter and thyroid autonomy in younger subjects and reduced frequency of nonautoimmune hyperthyroidism in older subjects) far outweighs the risk of development of thyroid autoimmunity and mild hypothyroidism in youngsters.
Collapse
Affiliation(s)
- F Aghini Lombardi
- Department of Endocrinology and Metabolism, University of Pisa, via Paradisa 2, 56100 Pisa, Italy
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Pearce EN. Monitoring and effects of iodine deficiency in pregnancy: still an unsolved problem? Eur J Clin Nutr 2013; 67:481-4. [DOI: 10.1038/ejcn.2012.215] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
|
6
|
Abstract
Dietary iodine requirements are increased in pregnancy due to increased thyroid hormone production, increased renal iodine losses, and fetal iodine requirements. Adverse effects of iodine deficiency in pregnancy include maternal and fetal goiter, cretinism, intellectual impairments, neonatal hypothyroidism, and increased pregnancy loss and infant. Dietary iodine requirements remain increased in lactation due to the concentration of iodine in breast milk. Iodine deficiency remains a significant global public health problem. Excess iodine ingestion in pregnancy, while a relatively uncommon problem, may also have adverse fetal effects. However, the safe upper limit for chronic iodine ingestion in pregnancy and lactation is not currently well defined.
Collapse
Affiliation(s)
- Elizabeth N Pearce
- Section of Endocrinology, Diabetes, and Nutrition, Boston University School of Medicine, Boston, MA 02118, USA.
| |
Collapse
|
7
|
|
8
|
Abstract
Iodine is a necessary element for the production of thyroid hormone. We will review the impact of dietary iodine status on thyroid function in pregnancy. We will discuss iodine metabolism, homeostasis, and nutritional recommendations for pregnancy. We will also discuss the possible effects of environmental contaminants on iodine utilization in pregnant women.
Collapse
Affiliation(s)
- Christina Yarrington
- Department of Obstetrics and Gynecology, Boston Medical Center, Boston, MA 02118, USA
| | - Elizabeth N. Pearce
- Section of Endocrinology, Diabetes, and Nutrition, Boston University School of Medicine, 88 East Newton Street, Evans 201, Boston, MA 02118, USA
| |
Collapse
|
9
|
Abstract
BACKGROUND Iodine deficiency disorders (IDD) constitute significant public health problems in parts of the world with poor iodine nutrition, but have been eradicated in North America and other regions. We herein report 3 cases of IDD, which occurred in women living in iodine-replete environments. METHODS The clinical presentation, biochemical findings, and radiological features of the patients were analyzed and presented in 3 case reports. The radiological features are illustrated in sonographic and scintigraphic images. A literature review and discussion, which highlight the risk factors, pathogenesis, ancillary investigations, and rational treatment of iodine deficiency goiter and hypothyroidism are provided. RESULTS All 3 patients were young women, aged 24 to 38 years, who had goiter. Two of them presented with goitrous hypothyroidism. Radioactive iodine scintigraphy showed a characteristic finding of diffusely increased uptake (in the absence of clinical and biochemical evidence of hyperthyroidism). This scintigraphic pattern was found to be pathognomonic. Dietary iodine supplementation alone resulted in complete remission of IDD in the subjects, including the 2 patients with hypothyroidism. CONCLUSION IDD can occur in iodine-replete environments. A high index of suspicion is needed to recognize these cases. It is pertinent that the correct diagnosis be made to avoid unwarranted life-long thyroxine therapy in patients presenting with goiter and hypothyroidism, which is easily treatable with iodized salt. These cases underscore the need for considering iodine deficiency in the etiologic diagnosis of goiter and hypothyroidism, even in iodine-sufficient regions.
Collapse
|
10
|
Iodine requirements during pregnancy, lactation and the neonatal period and indicators of optimal iodine nutrition. Public Health Nutr 2008; 10:1571-80; discussion 1581-3. [PMID: 18053281 DOI: 10.1017/s1368980007360941] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE This paper re-evaluates the requirements for iodine during pregnancy, lactation and the neonatal period, and formulates original proposals for the median concentrations of urinary iodine (UI) that indicate optimal iodine nutrition during these three critical periods of life. This paper also discusses the measurements that are used to explore thyroid functions during the same periods. DESIGN An extensive and critical review of the literature on thyroid physiopathology during the perinatal period. SETTING Human studies conducted in various regions throughout the world. SUBJECTS Pregnant women, lactating women, and newborns. RESULTS The following proposals are made after extensive review of the literature: the requirement for iodine by the mother during pregnancy is 250-300 microg day-1; during lactation the requirement is 225-350 microg day-1; and during the neonatal period the requirement of the infant is 90 microg day-1. The median UI that indicates an optimal iodine nutrition during these three periods should be in the range of 150-230 microg day-1. These figures are higher than recommended to date by the international agencies. CONCLUSIONS Pregnant women and young infants, but especially the second group, are more sensitive to the effects of an iodine deficiency (ID) than the general population because their serum thyroid-stimulating hormone (TSH) and thyroxine are increased and decreased, respectively, for degrees of ID that do not seem to affect thyroid function in the general population. Systematic neonatal thyroid screening using primary TSH could be the most sensitive indicator to monitor the process of ID control.
Collapse
|
11
|
Becker DV, Braverman LE, Delange F, Dunn JT, Franklyn JA, Hollowell JG, Lamm SH, Mitchell ML, Pearce E, Robbins J, Rovet JF. Iodine supplementation for pregnancy and lactation-United States and Canada: recommendations of the American Thyroid Association. Thyroid 2006; 16:949-51. [PMID: 17042677 DOI: 10.1089/thy.2006.16.949] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The fetus is totally dependent in early pregnancy on maternal thyroxine for normal brain development. Adequate maternal dietary intake of iodine during pregnancy is essential for maternal thyroxine production and later for thyroid function in the fetus. If iodine insufficiency leads to inadequate production of thyroid hormones and hypothyroidism during pregnancy, then irreversible fetal brain damage can result. In the United States, the median urinary iodine (UI) was 168 microg/L in 2001-2002, well within the range of normal established by the World Health Organization (WHO), but whereas the UI of pregnant women (173 microg/L; 95% CI 75-229 microg/L) was within the range recommended by WHO (150-249 microg/L), the lower 95% CI was less than 150 microg/L. Therefore, until additional physiologic data are available to make a better judgment, the American Thyroid Association recommends that women receive 150 microg iodine supplements daily during pregnancy and lactation and that all prenatal vitamin/mineral preparations contain 150 microg of iodine.
Collapse
|
12
|
Bazrafshan HR, Mohammadian S, Ordookhani A, Farhidmehr F, Hedayati M, Abdolahi N, Azizi F, Braverman LE, Pearce EN. Prevalence of goiter among schoolchildren from Gorgan, Iran, a decade after national iodine supplementation: association with age, gender, and thyroperoxidase antibodies. J Endocrinol Invest 2005; 28:727-33. [PMID: 16277169 DOI: 10.1007/bf03347556] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND One decade after universal salt iodization in Iran, goiter prevalence, urinary iodine concentration (UIC) and thyroperoxidase antibody (TPOAb) values were assessed among schoolchildren in Gorgan, Iran. METHODS From 2003-2004, 500 girls and 900 boys aged 7-11 yr were evaluated for goiter by palpation. UIC was measured in 183 randomly-selected goitrous children. Serum TSH, T4, and TPOAb were measured in 53 goitrous and 30 non-goitrous children with adequate UIC. RESULTS Goiter was detected in 370 (26.4%) children. Goiter was present in 31% of girls and 17% of boys age 9 (p<0.012); 37% of girls and 20% of boys age 10 (p<0.003); and 52% of girls and 19% of boys age 11 (p<0.0001). Median (range) UIC for all goitrous children sampled was 190 (20-600) microg/l; 220 (30590) in boys and 170 (20-600) in girls (p=0.001). Eight point seven percent of goitrous children and 22% of goitrous girls aged 10-11 had UIC<100 microg/l, while 47% of the goitrous children had UIC> or =200 microg/ l. TPOAb was present in 52.8% of goitrous children and 10% of non-goitrous children (p=0.0001). TPOAb was present in 53.9% of 10-11 and 22.7% of 7-9 yr old goitrous and non-goitrous children (p=0.003) with adequate UIC. Median (range) TSH was 2.9 (0.3-10.9) mlU/I in TPO-positive and 1.8 (0.5-4.1) in TPO-negative children (p=0.001). CONCLUSIONS Gorgan, Iran, is an iodine-sufficient area and almost half of schoolchildren have more than adequate UIC. TPOAb is associated with endemic goiter. Despite sufficient UIC overall, some school-aged girls remain at risk of iodine deficiency.
Collapse
Affiliation(s)
- H R Bazrafshan
- Gorgan Faculty of Medicine, Golestan University of Medical Sciences, Gorgan, Iran
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Opinion of the Scientific Panel on additives and products or substances used in animal feed (FEEDAP) on the use of iodine in feedingstuffs. EFSA J 2005. [DOI: 10.2903/j.efsa.2005.168] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
|
14
|
Delange F, de Benoist B, Pretell E, Dunn JT. Iodine deficiency in the world: where do we stand at the turn of the century? Thyroid 2001; 11:437-47. [PMID: 11396702 DOI: 10.1089/105072501300176390] [Citation(s) in RCA: 171] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Iodine deficiency is the leading cause of preventable mental retardation. Universal salt iodization (USI), calling for all salt used in agriculture, food processing, catering and household to be iodized, is the agreed strategy for achieving iodine sufficiency. This article reviews published information on programs for the sustainable elimination of the iodine deficiency disorders and reports new data on monitoring and impact of salt iodization programs at the population level. Currently, 68% of households from areas of the world with previous iodine deficiency have access to iodized salt, compared to less than 10% a decade ago. This great achievement, a public health success unprecedented in the field of noncommunicable diseases, must be better recognized by the health sector, including thyroidologists. On the other hand, the managers and sponsors of programs of iodized salt must appreciate the continuing need for greatly improved monitoring and quality control. For example, partnership evaluation of iodine nutrition using the ThyroMobil model in 35,223 schoolchildren at 378 sites of 28 countries has shown that many previously iodine deficient parts of the world now have median urinary iodine concentrations well above 300 microg/L, which is excessive and carries the risk of adverse health consequences. The elimination of iodine deficiency is within reach but major additional efforts are required to cover the whole population at risk and to ensure quality control and sustainability.
Collapse
Affiliation(s)
- F Delange
- International Council for Control of Iodine Deficiency Disorders, Brussels, Belgium.
| | | | | | | |
Collapse
|
15
|
Abstract
In 1990, iodine deficiency affected almost one-third of the world population and was the greatest single cause of preventable brain damage and mental retardation. Following a resolution adopted by the World Summit for Children in 1990. major programmes of iodine supplementation were implemented by the governments of the affected countries with the support of major donors. Iodisation of salt was recognised as the method of choice. Nine years later, by April 1999, 75% of the affected countries had legislation on salt iodisation and 68% of the affected populations had access to iodised salt. The prevalence of iodine deficiency disorders decreased drastically in most countries and the deficiency disappeared completely in some such as Peru. This result constitutes a public heath success unprecedented with a non-infectious disease. However, occasional adverse effects occurred. The principle effect is iodine-induced hyperthyroidism which occurs essentially in older people with autonomous nodular goitres, especially following iodine intake that is too rapid and of too massive an increment. The incidence of the disorder is usually low and reverts spontaneously to the background rate of hyperthyroidism or even below this rate after 1 to 10 years of iodine supplementation. The possible occurrence of iodine-induced thyroiditis in susceptible individuals has not been clearly demonstrated by large epidemiological surveys. Iodine supplementation is followed by an increased prevalence of occult papillary carcinoma of the thyroid discovered at autopsy but the prognosis of thyroid cancer is improved due to a shift towards differentiated forms of thyroid cancer that are diagnosed at earlier stages. Iodine-induced hyperthyroidism and other adverse effects can be almost entirely avoided by adequate and sustained quality control and monitoring of iodine supplementation which should also confirm adequate iodine intake. Available evidence clearly confirms that the benefits of correcting iodine deficiency far outweigh the risks of iodine supplementation.
Collapse
Affiliation(s)
- F Delange
- International Council for Control of Iodine Deficiency Disorders, Brussels, Belgium.
| | | |
Collapse
|