Correlation Between Drinking Water and Iodine Status: a Systematic Review and Meta-analysis.

Iodine is a micronutrient essential for maintaining normal body functioning, and the consumption depends on the distribution in the environment, and insufficient or excessive intake results in thyroid dysfunction. The purpose of this review was to evaluate the correlation between iodine concentration in drinking water and the iodine status of the population. The systematic review was conducted following the PRISMA guidelines and was registered at the International Prospective Register of Ongoing Systematic Reviews (CRD42019128308). A literature search was conducted using MEDLINE/PUBMED (National Library of Medicine), LILACS (Latin-American and Caribbean Literature on Health Sciences), and Cochrane Library, June 2021. The quality of the studies was assessed by a checklist for cross-sectional studies developed by Joanna Briggs Institute. The initial search identified 121 articles, out of which ten were included in this systematic review, and five were included in the meta-analysis. Among the articles listed, six adopted cutoff points to classify the iodine content in the drinking water. The study identified median iodine concentration in drinking water from 2.2 to 617.8 µg/L and the correlation between iodine concentration in drinking water and urinary iodine concentration was 0.92, according to meta-analysis. Furthermore, the iodine status was correlated to the iodine content in water. The determination of a cutoff point can contribute to the implementation of iodine consumption control measures.

Assessment of the Impact of Salt Iodisation Programmes on Urinary Iodine Concentrations and Goitre Rates: A Systematic Review.

INTRODUCTION: Two main strategies are currently recommended for the prevention and control of iodine deficiency in the world: implementation of universal salt iodisation programmes and permanent monitoring of iodine consumption by the population. Although iodine intake and coverage iodised salt have increased in the world population, iodine deficiency disorders (IDDs) may still be a public health problem in a few countries or communities. OBJECTIVE: To assess the impact of salt iodisation programmes on urinary iodine concentrations and goitre rates in the world population. Methodology. A systematic review based on the PRISMA method. We obtained articles from Scopus, Science Direct, MEDLINE databases, and other sources between March and April 2020, without limitation of dates. "Iodisation" AND "urinary iodine concentrations" AND "goitre" in English, Portuguese, and Spanish without filters and clinical trial, case-control, and cross-sectional studies were included in this review. RESULTS: Of 479 abstracts, twenty-three were eligible. Coverage on iodised salt was in the range of 16 to 98%, and 11 studies had been sufficient, whilst eight studies had adequate iodine concentration in salt and three excess. 81.8% of studies that had an adequate median of UIC had a good impact in their respective salt iodisation programmes. CONCLUSION: After 18 years of salt iodisation programme implementation in the 13 countries, the majority achieved sustaining elimination of IDD whilst all had adequate median UIC; however, more detailed studies are still needed to confirm that all communities are equally protected of IDD.

Implications of iodine deficiency by gestational trimester: a systematic review.

As pregnant women are susceptible to changes in iodine, which can cause miscarriage, goiter, thyroid nodules, hypothyroidism, in addition to fetal neurological impairment or development. The aim of this study was to verify the implications of the iodine alteration in each gestational trimester and its consequences of physiological justification. The review was based on PRISMA. Searching for articles that took place in March 2020 without delimiting data. As bases consulted were the Clinical Trials, Cochrane Library, Lilacs and Medline (PubMed). The descriptors were combined as follows: "pregnancy" AND "iodine deficiency". Articles that addressed iodine deficiency and its implications were included. The selection followed the steps of reading the titles, abstracts and full articles. To assess the methodological quality of the studies, the STROBE Instruction instrument was used. The research resulted in 1,266 studies and 11 were included. In assessing methodological quality, the lowest score was and the maximum 20. According to studies, the fourth most affected by iodine loss are the second and third, it is possible to increase the volume and pneumatic nodules, subclinical hypothyroidism, pre-eclampsia, among others. The damages caused by iodine deficiency in the first or second trimester are still reversible, therefore, they need to be diagnosed early, to guarantee an iodic homeostasis and prevent damage to the health of the mother-child binomial.

Ingestion of supplements and fortified food with iodine on the breast milk iodine concentration in deficiency areas: a systematic review.

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.

Implications of iodine deficiency by gestational trimester: a systematic review

ABSTRACT As pregnant women are susceptible to changes in iodine, which can cause miscarriage, goiter, thyroid nodules, hypothyroidism, in addition to fetal neurological impairment or development. The aim of this study was to verify the implications of the iodine alteration in each gestational trimester and its consequences of physiological justification. The review was based on PRISMA. Searching for articles that took place in March 2020 without delimiting data. As bases consulted were the Clinical Trials, Cochrane Library, Lilacs and Medline (PubMed). The descriptors were combined as follows: "pregnancy" AND "iodine deficiency". Articles that addressed iodine deficiency and its implications were included. The selection followed the steps of reading the titles, abstracts and full articles. To assess the methodological quality of the studies, the STROBE Instruction instrument was used. The research resulted in 1,266 studies and 11 were included. In assessing methodological quality, the lowest score was and the maximum 20. According to studies, the fourth most affected by iodine loss are the second and third, it is possible to increase the volume and pneumatic nodules, subclinical hypothyroidism, pre-eclampsia, among others. The damages caused by iodine deficiency in the first or second trimester are still reversible, therefore, they need to be diagnosed early, to guarantee an iodic homeostasis and prevent damage to the health of the mother-child binomial.