1
|
Doggui R, McCormick BJ, Caulfield LE, Schulze KJ, Murray-Kolb LE. Adequacy of Iodine Status and Associations with Gut Health: A Prospective Cohort Study among Infants in 8 Low- and Middle-Income Countries. J Nutr 2023; 153:828-838. [PMID: 36797135 DOI: 10.1016/j.tjnut.2022.11.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 10/25/2022] [Accepted: 11/15/2022] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Environmental enteric dysfunction increases the likelihood of micronutrient deficiencies among infants, but few studies have assessed the potential impact of gut health on urinary iodine concentration (UIC) among this vulnerable group. OBJECTIVES We describe the trends of iodine status among infants from 6 to 24 mo old and examine the associations between intestinal permeability, inflammation, and UIC from 6 to 15 mo of age. METHODS Data from 1557 children enrolled in this birth cohort study conducted in 8 sites were included in these analyses. UIC was measured at 6, 15, and 24 mo of age by using the Sandell-Kolthoff technique. Gut inflammation and permeability were assessed using the concentrations of fecal neopterin (NEO), myeloperoxidase (MPO) and alpha-1-antitrypsin (AAT), and lactulose-mannitol ratio (LM). A multinomial regression analysis was used to assess the classified UIC (deficiency or excess). Linear mixed regression was used to test the effect of interactions among biomarkers on logUIC. RESULTS All studied populations had adequate (≥100 μg/L) to excess (≥371 μg/L) median UIC at 6 mo. Between 6 and 24 mo, 5 sites displayed a significant decline in the infant's median UIC. However, median UIC remained within the optimal range. An increase of NEO and MPO concentrations by +1 unit in ln scale reduced the risk of low UIC by 0.87 (95% CI: 0.78-0.97) and 0.86 (95% CI: 0.77-0.95), respectively. AAT moderated the association between NEO and UIC (P < 0.0001). The shape of this association appears to be asymmetric and in a reverse J-shape, with a higher UIC observed at both lower NEO and AAT concentrations. CONCLUSIONS Excess UIC was frequent at 6 mo and tended to normalize at 24 mo. Aspects of gut inflammation and increased permeability appear to reduce the prevalence of low UIC in children aged 6 to 15 mo. Programs addressing iodine-related health should consider the role of gut permeability in vulnerable individuals.
Collapse
Affiliation(s)
- Radhouene Doggui
- Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA, USA.
| | | | - Laura E Caulfield
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Kerry J Schulze
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Laura E Murray-Kolb
- Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA, USA; Department of Nutrition Science, Purdue University, West Lafayette, IN, USA
| | | |
Collapse
|
2
|
Breast Milk Iodine Concentration (BMIC) as a Biomarker of Iodine Status in Lactating Women and Children <2 Years of Age: A Systematic Review. Nutrients 2022; 14:nu14091691. [PMID: 35565659 PMCID: PMC9104537 DOI: 10.3390/nu14091691] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 03/28/2022] [Accepted: 04/01/2022] [Indexed: 01/01/2023] Open
Abstract
Background: Iodine is needed for the production of thyroid hormones, which are essential for infant growth and development. Given that there are wide variations in breast milk iodine concentration (BMIC) and urinary iodine concentration (UIC), it is unclear if BMIC is associated with UIC in populations residing in iodine sufficient or deficient areas. Aim: To investigate if BMIC can be used as a biomarker for iodine status in lactating women and children <2 years of age. Methods: Electronic databases; PubMed, Web of Science and Scopus were searched until year 2021, for studies investigating the relationship between BMIC and UIC. Studies were reviewed for eligibility, according to inclusion and exclusion criteria, followed by data extraction, according to the PRISMA guidelines. Results: Overall, 51 studies met the criteria for inclusion in the systematic review. BMIC ranged from 18 to 1153 µg/L. In iodine-deficient and iodine-sufficient lactating women, BMIC ranged from 26 to 185 µg/L and 15 to 1006 µg/L, respectively. In most studies, the categorisation of iodine status assessed by median UIC was consistent with the categorisation of iodine status assessed by median BMIC cut off of ≥100 µg/L, to determine iodine sufficiency in lactating women and children <2 years of age. Conclusions: The systematic review indicated that BMIC is a promising biomarker of iodine status in lactating women and children <2 years of age. However, these data need to be interpreted cautiously, given the study limitations in the included studies. Future studies should consider investigating the optimal median BMIC, as there is a lack of high-quality observational and intervention studies in lactating women and infants.
Collapse
|
3
|
Galvão VE, Cavalli RC, Sandrim VC. Preeclampsia and Gestational Hypertension: Biochemical and Antioxidant Features in Vitro Might Help Understand Different Outcomes. REVISTA BRASILEIRA DE GINECOLOGIA E OBSTETRÍCIA 2021; 43:894-903. [PMID: 34933382 PMCID: PMC10183867 DOI: 10.1055/s-0041-1740270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
OBJECTIVE Gestational hypertension (GH) is characterized by increased blood pressure after the 20th gestational week; the presence of proteinuria and/or signs of end-organ damage indicate preeclampsia (PE). Heme oxygenase-1 (HO-1) is an antioxidant enzyme with an important role in maintaining endothelial function, and induction of HO-1 by certain molecules shows potential in attenuating the condition's effects over endothelial tissue. HO-1 production can also be stimulated by potassium iodide (KI). Therefore, we evaluated the effects of KI over HO-1 expression in human umbilical vein endothelial cells (HUVECs) incubated with plasma from women diagnosed with GH or PE. METHODS Human umbilical vein endothelial cells were incubated with a pool of plasma of healthy pregnant women (n = 12), pregnant women diagnosed with GH (n = 10) or preeclamptic women (n = 11) with or without the addition of KI for 24 hours to evaluate its effect on this enzyme expression. Analysis of variance was performed followed by Dunnet's test for multiple comparisons between groups only or between groups with addition of KI (p ≤ 0.05). RESULTS KI solution (1,000 µM) reduced HO-1 in the gestational hypertension group (p = 0.0018) and cytotoxicity in the preeclamptic group (p = 0.0143); treatment with KI reduced plasma cytotoxicity but did not affect the preeclamptic group's HO-1 expression. CONCLUSION Our findings suggest that KI alleviates oxidative stress leading to decreased HO-1 expression; plasma from preeclamptic women did not induce the enzyme's expression in HUVECs, and we hypothesize that this is possibly due to inhibitory post-transcriptional mechanisms in response to overexpression of this enzyme during early pregnancy.
Collapse
Affiliation(s)
- Victoria Elizabeth Galvão
- Department of Pharmacology, Instituto de Biociências, Universidade Estadual Paulista, Botucatu, SP, Brazil
| | - Ricardo Carvalho Cavalli
- Department of Obstetrics and Gynecology, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Valeria Cristina Sandrim
- Department of Pharmacology, Instituto de Biociências, Universidade Estadual Paulista, Botucatu, SP, Brazil.,Center for Toxicological Assistance, Instituto de Biociências, Universidade Estadual Paulista, Botucatu, SP, Brazil
| |
Collapse
|
4
|
Machamba AAL, Priore SE, Macedo MDS, Franceschini SDCC. Ingestion of supplements and fortified food with iodine on the breast milk iodine concentration in deficiency areas: a systematic review. Afr Health Sci 2021; 21:1346-1354. [PMID: 35222600 PMCID: PMC8843278 DOI: 10.4314/ahs.v21i3.46] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Introduction The level of iodine in breast milk may be inadequate and compromise the health of this, both due to excess and lack, some population groups remain deficient because of the low consumption of iodate salt, because there is an increase in consumption of other sources of iodine, such as supplements and fortified foods. Objective To evaluate the effect of the consumption of fortified foods and nutritional supplements with iodine on maternal milk levels. Methodology Systematic review based on the Prism method, using the descriptors provided by DeCS. The reading, selection and analysis of the methodological quality of the articles was done by two researchers independently. Results From 346 abstracts, 6 were eligible. The median iodination range between the studies ranged from 75 to 600 µg in supplements and 150 and 225 µg in fortified foods with effect on increased iodine concentration of breastmilk (BMIC), achieving the adequacy of the median BMIC in 4 of the 6 studies. Conclusion Iodine ingestion through supplements or fortified foods results in improved iodine levels in breast milk.
Collapse
Affiliation(s)
- Almeida Abudo Leite Machamba
- Almeida A. L. Machamba: PhD Student in the Postgraduate Program in Nutrition Science, Department of Nutrition and Health, Federal University of Viçosa (UFV), Viçosa, Brazil
| | - Silvia Eloiza Priore
- Full PhD Professor in the the Postgraduate Program in Nutrition Science, Department of Nutrition and Health, Federal University of Viçosa (UFV), Viçosa, Brazil
| | - Mariana de Souza Macedo
- Post-Doctoral in the Postgraduate Program in Nutrition Science, Department of Nutrition and Health, Federal University of Viçosa (UFV), Viçosa, Brazil
| | - Sylvia do Carmo Castro Franceschini
- Full PhD Professor in the the Postgraduate Program in Nutrition Science, Department of Nutrition and Health and Pro-Rector of community affairs, Federal University of Viçosa (UFV), Viçosa, Brazil
| |
Collapse
|
5
|
Themelin C, Pierron C, Calafat JF, de Beaufort C. Transient neonatal hypothyroidism secondary to postnatal maternal exposure to contrast medium. BMJ Case Rep 2019; 12:12/10/e230854. [PMID: 31619400 DOI: 10.1136/bcr-2019-230854] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
We report a preterm breastfed infant who developed a transient hypothyroidism after his lactating mother had a CT scan with iodinated contrast medium, despite the advised 24 hours' pause in breast feeding. The aetiological assessment did not show any other cause for this hypothyroidism. Transient neonatal hypothyroidism after the use of topical iodine is well known, but it has not been described as a complication of intravenous contrast medium administration to a lactating mother. This case highlights the possibility of transient neonatal hypothyroidism secondary to contrast medium exposure to a lactating mother. When imaging is needed in the lactating mother, a longer break in breast feeding might be needed to prevent transient hypothyroidism in the preterm infant.
Collapse
Affiliation(s)
- Céline Themelin
- Pediatrics, Centre Hospitalier du Luxembourg, Luxembourg, Luxembourg
| | - Charlotte Pierron
- Pediatrics, Centre Hospitalier du Luxembourg, Luxembourg, Luxembourg
| | | | - Carine de Beaufort
- Pediatrics, Centre Hospitalier du Luxembourg, Luxembourg, Luxembourg .,Pediatrics, Universitair Ziekenhuis Brussel, Brussel, Belgium
| |
Collapse
|
6
|
Dumrongwongsiri O, Chatvutinun S, Phoonlabdacha P, Sangcakul A, Chailurkit LO, Siripinyanond A, Suthutvoravut U, Chongviriyaphan N. High Urinary Iodine Concentration Among Breastfed Infants and the Factors Associated with Iodine Content in Breast Milk. Biol Trace Elem Res 2018; 186:106-113. [PMID: 29549532 DOI: 10.1007/s12011-018-1303-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 03/07/2018] [Indexed: 10/17/2022]
Abstract
Iodine deficiency in infants leads to delayed growth and development. Some studies have reported iodine deficiency among infants and lactating women. We assessed iodine status in infants and lactating women, as well as the iodine content in breast milk. A cross-sectional study enrolled mother-infant pairs (infants aged 4-6 months), who visited Well Child Clinic at Ramathibodi Hospital, Bangkok, Thailand. Infants were classified by feeding type as breastfed (BF), mixed breastfed and formula-fed (MF), and formula-fed (FF). Demographic and perinatal data were collected. The urinary iodine concentration (UIC) of infants and lactating women, and breast milk iodine concentration (BMIC) were analyzed. Seventy-one infants were enrolled. The median UIC of infants was 282 mcg/L. Breastfed infants had higher median UIC than formula-fed infants (553 vs. 192 mcg/L; p = 0.002). Forty-eight percent of infants had a UIC more than 300 mcg/L. The median UIC and BMIC of lactating women were 149 and 255 mcg/L, respectively. Among the BF group, the infant UIC was correlated with maternal UIC (rs = 0.857, p = 0.014). Multiple linear regression showed the BMIC to be associated with maternal UIC (β = 4.03, 95% CI [1.34, 6.71]) and maternal weight (β = 8.26, 95%CI [2.76, 13.77]). Iodine nutrition among our study population was adequate. The median UIC of infants and lactating mothers were 282 and 149 mcg/L, respectively. Breastfed infants had a significantly higher median UIC than formula-fed infants. The BMIC was associated with maternal UIC and maternal weight.
Collapse
Affiliation(s)
- Oraporn Dumrongwongsiri
- Division of Nutrition, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 270 Rama VI Road, Ratchathewi, Bangkok, 10400, Thailand.
| | - Suthida Chatvutinun
- Pediatrics Nursing Division, Nursing Service Department, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 270 Rama VI Road, Ratchathewi, Bangkok, 10400, Thailand
| | - Phanphen Phoonlabdacha
- Division of Nutrition, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 270 Rama VI Road, Ratchathewi, Bangkok, 10400, Thailand
| | - Areeporn Sangcakul
- Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 270 Rama VI Road, Ratchathewi, Bangkok, 10400, Thailand
| | - La-Or Chailurkit
- Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 270 Rama VI Road, Ratchathewi, Bangkok, 10400, Thailand
| | - Atitaya Siripinyanond
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University, 272 Rama VI Road, Ratchathewi, Bangkok, 10400, Thailand
| | - Umaporn Suthutvoravut
- Division of Nutrition, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 270 Rama VI Road, Ratchathewi, Bangkok, 10400, Thailand
| | - Nalinee Chongviriyaphan
- Division of Nutrition, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 270 Rama VI Road, Ratchathewi, Bangkok, 10400, Thailand
| |
Collapse
|
7
|
Farebrother J, Zimmermann MB, Abdallah F, Assey V, Fingerhut R, Gichohi-Wainaina WN, Hussein I, Makokha A, Sagno K, Untoro J, Watts M, Andersson M. Effect of Excess Iodine Intake from Iodized Salt and/or Groundwater Iodine on Thyroid Function in Nonpregnant and Pregnant Women, Infants, and Children: A Multicenter Study in East Africa. Thyroid 2018; 28:1198-1210. [PMID: 30019625 DOI: 10.1089/thy.2018.0234] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Acute excess iodine intake can damage the thyroid, but the effects of chronic excess iodine intake are uncertain. Few data exist for pregnant and lactating women and infants exposed to excessive iodine intake. METHODS This was a multicenter cross-sectional study. At study sites in rural Kenya and urban Tanzania previously reporting iodine excess in children, urinary iodine concentration (UIC), thyrotropin, total thyroxine, and thyroglobulin (Tg) were measured in school-age children (SAC), women of reproductive age, pregnant (PW) and lactating women, and breast-feeding and weaning infants. In a national study in Djibouti, UIC was measured in SAC and PW. At all sites, daily iodine intake was estimated based on UIC, and iodine concentration was measured in household salt and drinking water. RESULTS The total sample size was 4636: 1390, 2048, and 1198 subjects from Kenya, Tanzania, and Djibouti, respectively. In Kenya and Tanzania: (i) median UIC was well above thresholds for adequate iodine nutrition in all groups and exceeded the threshold for excess iodine intake in SAC; (ii) iodine concentrations >40 mg of iodine/kg were found in approximately 55% of household salt samples; (iii) iodine concentrations ≥10 μg/L were detected in 9% of drinking water samples; (iv) Tg was elevated in all population groups, but the prevalence of thyroid disorders was negligible, except that 5-12% of women of reproductive age had subclinical hyperthyroidism and 10-15% of PW were hypothyroxinemic. In Djibouti: (i) the median UIC was 335 μg/L (interquartile range [IQR] = 216-493 μg/L) in SAC and 265 μg/L (IQR = 168-449 μg/L) in PW; (ii) only 1.6% of Djibouti salt samples (n = 1200) were adequately iodized (>15 mg/kg); (iii) the median iodine concentration in drinking water was 92 μg/L (IQR = 37-158 μg/L; n = 77). In all countries, UIC was not significantly correlated with salt or water iodine concentrations. CONCLUSIONS Although iodine intake was excessive and Tg concentrations were elevated, there was little impact on thyroid function. Chronic excess iodine intake thus appears to be well tolerated by women, infants, and children. However, such high iodine intake is unnecessary and should be avoided. Careful evaluation of contributions from both iodized salt and groundwater iodine is recommended before any review of iodization policy is considered.
Collapse
Affiliation(s)
- Jessica Farebrother
- 1 Human Nutrition Laboratory, Institute of Food, Nutrition, and Health , ETH Zurich, Zurich, Switzerland
| | - Michael B Zimmermann
- 1 Human Nutrition Laboratory, Institute of Food, Nutrition, and Health , ETH Zurich, Zurich, Switzerland
- 2 Iodine Global Network , Ottawa, Canada
| | - Fatma Abdallah
- 3 Tanzania Food and Nutrition Centre , Dar es Salaam, Tanzania
| | - Vincent Assey
- 4 Nutrition Services Section, Preventive Services Department, Ministry of Health , Community Development, Gender, Elderly, and Children, Dar es Salaam, Tanzania
- 5 Regional Coordinator East and Southern Africa, Iodine Global Network , Ottawa, Canada
| | - Ralph Fingerhut
- 6 University Children's Hospital Zurich , Swiss Newborn Screening Laboratory and Children's Research Center, Zurich, Switzerland
| | - Wanjiku N Gichohi-Wainaina
- 7 International Crops Research Institute for Semi-Arid Tropics (ICRISAT) , Lilongwe, Malawi
- 8 Department of Food Science, Jomo Kenyatta University of Agriculture and Technology , Nairobi, Kenya
| | - Izzeldin Hussein
- 9 Regional Coordinator Middle East and North Africa, Iodine Global Network , Ottawa, Canada
| | - Anselimo Makokha
- 8 Department of Food Science, Jomo Kenyatta University of Agriculture and Technology , Nairobi, Kenya
| | - Kalil Sagno
- 10 Djibouti Country Office, United Nations Children's Fund , Djibouti, Djibouti
| | - Juliawati Untoro
- 11 Eastern and Southern Africa Regional Office, United Nations Children's Fund , Nairobi, Kenya
| | - Michael Watts
- 12 Inorganic Geochemistry, Centre for Environmental Geochemistry, British Geological Survey , Nottingham, United Kingdom
| | - Maria Andersson
- 1 Human Nutrition Laboratory, Institute of Food, Nutrition, and Health , ETH Zurich, Zurich, Switzerland
- 2 Iodine Global Network , Ottawa, Canada
- 13 Division of Gastroenterology and Nutrition, University Children's Hospital Zurich , Zurich, Switzerland
| |
Collapse
|
8
|
Lima LFD, Barbosa F, Simões MV, Navarro AM. Heart failure, micronutrient profile, and its connection with thyroid dysfunction and nutritional status. Clin Nutr 2018; 38:800-805. [PMID: 29551406 DOI: 10.1016/j.clnu.2018.02.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 02/12/2018] [Accepted: 02/25/2018] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Heart failure (HF) is a growing public health issue; its risk factors include inappropriate dietary intake of microelements such as iodine, selenium, zinc and iron, which may lead to thyroid dysfunction. OBJECTIVE This study aimed to assess the correlation among the functional class stages of patients with HF, iodine, selenium, iron and zinc levels with the presence of thyroid dysfunction. METHODOLOGY One hundred nine patients from the HF outpatient clinic of the Clinics Hospital of Ribeirão Preto whose blood and urine were collected for micronutrient analysis and laboratory tests were selected. The subjects' weight and height were also measured to calculate their BMI. First, a descriptive analysis of the data was made into tables, and then statistical analyses were done at a 5% significance level (p < 0.05). RESULTS Most patients whose data was analysed were elderly and overweight. Excess ioduria, serum selenium and zinc, erythrocyte zinc and deficiency in serum iron and erythrocyte selenium were observed. The prevalence of thyroid dysfunction was 8.3%. Multivariate logistic regression verified that thyroid dysfunction increases the chance of classification in functional class III or IV (p = 0.015; OR = 8.72) by 8.7 times; each year of age increases the chance by 4.6% of classification in functional class III or IV (p = 0.008; odds ratio [OR] = 1.05), and each unit of BMI increases the chance of classification in functional class III or IV by 9.2% (p = 0.028; OR = 1.09). CONCLUSION Patients with HF were deficient in serum iron and erythrocyte selenium. No connection was found between hypothyroidism and mineral deficiency, which seems to be related more to the severity of the disease than to the micronutrient nutritional profile.
Collapse
Affiliation(s)
- Livia Fernandes de Lima
- Department of Internal Medicine, Medical School of Ribeirão Preto, Avenida Bandeirantes 3900, Monte Alegre, 14049-900 Ribeirão Preto, SP, Brazil.
| | - Fernando Barbosa
- Department of Clinical, Toxicological and Bromatological Analyses, Faculty of Pharmacy of Ribeirão Preto, Avenida do Café s/n, Monte Alegre, 14049-903 Ribeirão Preto, SP, Brazil
| | - Marcus Vinícius Simões
- Department of Internal Medicine, Medical School of Ribeirão Preto, Avenida Bandeirantes 3900, Monte Alegre, 14049-900 Ribeirão Preto, SP, Brazil
| | - Anderson Marliere Navarro
- Department of Internal Medicine, Medical School of Ribeirão Preto, Avenida Bandeirantes 3900, Monte Alegre, 14049-900 Ribeirão Preto, SP, Brazil
| |
Collapse
|
9
|
Nazeri P, Kabir A, Dalili H, Mirmiran P, Azizi F. Breast-Milk Iodine Concentrations and Iodine Levels of Infants According to the Iodine Status of the Country of Residence: A Systematic Review and Meta-Analysis. Thyroid 2018; 28:124-138. [PMID: 29334343 DOI: 10.1089/thy.2017.0403] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Iodine, an essential micronutrient, plays a critical role in normal growth and development, especially during the first two years of life. This systematic review and meta-analysis is among the first to evaluate breast-milk iodine concentrations and infant iodine status in countries characterized by iodine sufficiency or deficiency. METHODS PubMed, Web of Science, Cochrane Library, Google Scholar, and other relevant databases, as well as reference lists of previous reviews, were searched for relevant studies published between 1986 and 2016. Mean or median breast-milk and infant urinary iodine concentrations, along with other relevant data, were extracted from eligible studies. Each study was assessed for quality and risk of bias. RESULTS Of the 496 identified studies, 57 met the criteria for inclusion in the meta-analysis. The mean (confidence interval [CI]) iodine concentrations in maternal colostrum were 152.0 μg/L [CI 106.2-198.7 μg/L] and 57.8 μg/L [CI 41.4-74.1 μg/L] in iodine-sufficient and -deficient countries, respectively, indicating a significant difference between the two iodine statuses. By contrast, the corresponding values in mature milk did not differ significantly between mothers in iodine-sufficient and -deficient countries (71.5 μg/L [CI 51.0-92.0 μg/L] and 28.0 μg/L [CI -13.8 to 69.9 μg/L], respectively]. The weighted urinary iodine levels [CIs] of breast-fed infants in iodine-sufficient countries were significantly higher than those in iodine-deficient countries (164.5 μg/L [CI 116.4-212.7 μg/L] vs. 70.4 μg/L [CI 46.2-94.6 μg/L]). Similarly, a significant difference was observed in the pooled estimates of urinary iodine levels [CIs] among formula-fed infants in iodine-sufficient versus iodine-deficient countries (310.3 μg/L [CI 287.4-342.1 μg/L] vs. 38.3 μg/L [CI 23.4-53.2 μg/L]). CONCLUSION The meta-analysis reveals that in iodine-sufficient countries, the mean iodine concentrations in colostrum and mature breast milk corresponded to iodine sufficiency among infants. The results are thus compatible with the international recommendation that lactating women and infants younger than two years of age who reside in iodine-sufficient countries do not require iodine supplementation.
Collapse
Affiliation(s)
- Pantea Nazeri
- 1 Family Health Institute, Breastfeeding Research Center, Tehran University of Medical Sciences , Tehran, Iran
- 2 Nutrition and Endocrine Research Center, Shahid Beheshti University of Medical Sciences , Tehran, Iran
| | - Ali Kabir
- 3 Minimally Invasive Surgery Research Center, Iran University of Medical Sciences , Tehran, Iran
| | - Hosein Dalili
- 1 Family Health Institute, Breastfeeding Research Center, Tehran University of Medical Sciences , Tehran, Iran
| | - Parvin Mirmiran
- 2 Nutrition and Endocrine Research Center, Shahid Beheshti University of Medical Sciences , Tehran, Iran
| | - Fereidoun Azizi
- 4 Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences , Tehran, Iran
| |
Collapse
|
10
|
Nepal AK, Suwal R, Gautam S, Shah GS, Baral N, Andersson M, Zimmermann MB. Subclinical Hypothyroidism and Elevated Thyroglobulin in Infants with Chronic Excess Iodine Intake. Thyroid 2015; 25:851-9. [PMID: 25950720 DOI: 10.1089/thy.2015.0153] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Acute iodine excess in newborns can cause hypothyroidism, but there are limited data on the effects of iodine excess on thyroid function in older infants. The aim of this study was to measure the effects of chronic excess iodine intake on thyroid function in 6-24-month-old infants. METHODS In this cross-sectional study, infants (n=696) in eastern Nepal were studied. Spot urine samples, venous blood samples, and household salt samples were collected, and urinary iodine concentration (UIC), serum free thyroxine (fT4), thyrotropin (TSH), thyroglobulin (Tg), and titrated household salt iodine concentration (SIC) were measured. Daily iodine intake was calculated from UIC based on estimates of urine volume at this age. RESULTS Median (25th-75th percentile) household SIC was 89 (70-149) ppm, while national legislation stipulates a fortification level of 50 ppm. Median UIC was 407 (312-491) μg/L; 76% of infants had a UIC >300 μg/L, suggesting iodine excess. Calculated mean iodine intake in 12-24-month-old infants was 220 μg/day, exceeding the recommended safe upper limit for iodine at this age (200 μg/day). Among the infants, 15.8% had an elevated Tg, 7.4% had subclinical hypothyroidism, but <1% had overt hypothyroidism. UIC was not a significant predictor of thyroid function, thyroid hormones, or Tg. CONCLUSION In 6-24-month-old infants exposed to excessive iodine intake, ∼7% have subclinical hypothyroidism but <1% have overt hypothyroidism. These findings suggest the thyroid in late infancy is already able to adapt to high iodine intakes and, in most cases, maintain euthyroidism.
Collapse
Affiliation(s)
- Ashwini Kumar Nepal
- 1 Department of Biochemistry, B.P. Koirala Institute of Health Sciences , Dharan, Nepal
| | - Ranjan Suwal
- 1 Department of Biochemistry, B.P. Koirala Institute of Health Sciences , Dharan, Nepal
| | - Sharad Gautam
- 1 Department of Biochemistry, B.P. Koirala Institute of Health Sciences , Dharan, Nepal
| | - Gauri Shankar Shah
- 2 Department of Pediatric and Adolescent Medicine, B.P. Koirala Institute of Health Sciences , Dharan, Nepal
| | - Nirmal Baral
- 1 Department of Biochemistry, B.P. Koirala Institute of Health Sciences , Dharan, Nepal
| | - Maria Andersson
- 3 Human Nutrition Laboratory, Institute of Food Nutrition and Health, Swiss Federal Institute of Technology (ETH) , Zurich, Switzerland
| | - Michael Bruce Zimmermann
- 3 Human Nutrition Laboratory, Institute of Food Nutrition and Health, Swiss Federal Institute of Technology (ETH) , Zurich, Switzerland
| |
Collapse
|
11
|
Campos RDO, Barreto IDS, Maia LRDJ, Rebouças SCL, Cerqueira TLDO, Oliveira CA, Santos CADST, Mendes CMC, Teixeira LSG, Ramos HE. Iodine nutritional status in Brazil: a meta-analysis of all studies performed in the country pinpoints to an insufficient evaluation and heterogeneity. ARCHIVES OF ENDOCRINOLOGY AND METABOLISM 2015; 59:13-22. [DOI: 10.1590/2359-3997000000004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 10/12/2014] [Indexed: 11/21/2022]
|