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Rigutto-Farebrother J, Zimmermann MB. Salt Reduction and Iodine Fortification Policies Are Compatible: Perspectives for Public Health Advocacy. Nutrients 2024; 16:2517. [PMID: 39125397 PMCID: PMC11314281 DOI: 10.3390/nu16152517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2024] [Revised: 07/24/2024] [Accepted: 07/25/2024] [Indexed: 08/12/2024] Open
Abstract
Cardiovascular diseases account for almost 18 million deaths annually, the most of all non-communicable diseases. The reduction of dietary salt consumption is a modifiable risk factor. The WHO recommends a daily sodium intake of <2000 mg but average consumption exceeds this in many countries globally. Strategies proposed to aid effective salt reduction policy include product reformulation, front of pack labelling, behavioural change campaigns and establishing a low-sodium-supportive environment. Yet, salt for household and processed food use is, in countries wholly or partially adopting a universal salt iodisation policy, the principal vehicle for population-wide iodine fortification. With salt reduction policies in place, there is concern that iodine deficiency disorders may re-emerge. Recognising the urgency to tackle the rising prevalence of NCDs yet not risk the re-emergence and detrimental effect of inadequate iodine intakes, this review lays out the feasibility of integrating both salt reduction and salt iodine fortification strategies. Reducing the burden of health risks associated with an excessive sodium intake or inadequate iodine through population-tailored, cost-effective strategies involving salt is both feasible and achievable, and represents an opportunity to improve outcomes in public health.
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Affiliation(s)
- Jessica Rigutto-Farebrother
- Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zürich, 8092 Zürich, Switzerland
- Laboratory of Nutrition and Metabolic Epigenetics, Institute of Food, Nutrition and Health, ETH Zürich, 8092 Zürich, Switzerland
| | - Michael B. Zimmermann
- Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zürich, 8092 Zürich, Switzerland
- MRC Human Immunology Unit, MRC Wetherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
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Mahwera D, Killel E, Jonas N, Hancy A, Zangira A, Lekey A, Msaki R, Katana D, Kishimba R, Charwe D, Abdallah F, Chiduo G, Masumo R, Leyna G, Mchau G. Evaluation of the Universal Salt Iodization (USI) surveillance system in Tanzania, 2022. PLoS One 2024; 19:e0299025. [PMID: 38640102 PMCID: PMC11029623 DOI: 10.1371/journal.pone.0299025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 02/02/2024] [Indexed: 04/21/2024] Open
Abstract
BACKGROUND The evaluation of surveillance systems has been recommended by the World Health Organization (WHO) to identify the performance and areas for improvement. Universal salt iodization (USI) as one of the surveillance systems in Tanzania needs periodic evaluation for its optimal function. This study aimed at evaluating the universal salt iodization (USI) surveillance system in Tanzania from January to December 2021 to find out if the system meets its intended objectives by evaluating its attributes as this was the first evaluation of the USI surveillance system since its establishment in 2010. The USI surveillance system is key for monitoring the performance towards the attainment of universal salt iodization (90%). METHODOLOGY This evaluation was guided by the Center for Disease Control Guidelines for Evaluating Public Health Surveillance Systems, (MMWR) to evaluate USI 2021 data. The study was conducted in Kigoma region in March 2022. Both Purposive and Convenient sampling was used to select the region, district, and ward for the study. The study involved reviewing documents used in the USI system and interviewing the key informants in the USI program. Data analysis was done by Microsoft Excel and presented in tables and graphs. RESULTS A total of 1715 salt samples were collected in the year 2021 with 279 (16%) of non-iodized salt identified. The majority of the system attributes 66.7% had a good performance with a score of three, 22.2% had a moderate performance with a score of two and one attribute with poor performance with a score of one. Data quality, completeness and sensitivity were 100%, acceptability 91.6%, simplicity 83% were able to collect data on a single sample in < 2 minutes, the system stability in terms of performance was >75% and the usefulness of the system had poor performance. CONCLUSION Although the system attributes were found to be working overall well, for proper surveillance of the USI system, the core attributes need to be strengthened. Key variables that measure the system performance must be included from the primary data source and well-integrated with the Local Government (district and regions) to Ministry of Health information systems.
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Affiliation(s)
- David Mahwera
- Department of Epidemiology and Biostatistics, Muhimbili University of Health and Allied Sciences, Dar es salaam, Tanzania
- Tanzania Field Epidemiology and Laboratory Training Program, Tanzania
| | - Erick Killel
- Department of Community Health and Nutrition, Tanzania Food and Nutrition Centre, Dar es salaam, Tanzania
| | - Ninael Jonas
- Department of Epidemiology and Biostatistics, Muhimbili University of Health and Allied Sciences, Dar es salaam, Tanzania
- Tanzania Field Epidemiology and Laboratory Training Program, Tanzania
| | - Adam Hancy
- Department of Nutrition Policy and Planning, Tanzania Food and Nutrition Center, Dar es salaam, Tanzania
| | - Anna Zangira
- Department of Community Health and Nutrition, Tanzania Food and Nutrition Centre, Dar es salaam, Tanzania
| | - Aika Lekey
- Department of Community Health and Nutrition, Tanzania Food and Nutrition Centre, Dar es salaam, Tanzania
| | - Rose Msaki
- Department of Community Health and Nutrition, Tanzania Food and Nutrition Centre, Dar es salaam, Tanzania
| | - Doris Katana
- Department of Nutrition Education and Training, Tanzania Food and Nutrition Centre, Dar es salaam, Tanzania
| | - Rogath Kishimba
- Tanzania Field Epidemiology and Laboratory Training Program, Tanzania
- Ministry of Health, Dodoma, Tanzania
| | - Debora Charwe
- Department of Nutrition Policy and Planning, Tanzania Food and Nutrition Center, Dar es salaam, Tanzania
| | - Fatma Abdallah
- Department of Community Health and Nutrition, Tanzania Food and Nutrition Centre, Dar es salaam, Tanzania
| | - Geofrey Chiduo
- Department of Nutrition Policy and Planning, Tanzania Food and Nutrition Center, Dar es salaam, Tanzania
| | - Ray Masumo
- Department of Community Health and Nutrition, Tanzania Food and Nutrition Centre, Dar es salaam, Tanzania
| | - Germana Leyna
- Department of Epidemiology and Biostatistics, Muhimbili University of Health and Allied Sciences, Dar es salaam, Tanzania
- Department of Community Health and Nutrition, Tanzania Food and Nutrition Centre, Dar es salaam, Tanzania
| | - Geofrey Mchau
- Department of Epidemiology and Biostatistics, Muhimbili University of Health and Allied Sciences, Dar es salaam, Tanzania
- Tanzania Field Epidemiology and Laboratory Training Program, Tanzania
- Department of Community Health and Nutrition, Tanzania Food and Nutrition Centre, Dar es salaam, Tanzania
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Davis JN, Kumordzie SM, Arnold CD, Wessells KR, Nyaaba KW, Adams KP, Tan XJ, Becher E, Vosti SA, Adu-Afarwuah S, Engle-Stone R. Consumption of Discretionary Salt and Salt from Bouillon among Households, Women, and Young Children in Northern Region, Ghana: A Mixed-Methods Study with the Condiment Micronutrient Innovation Trial (CoMIT) Project. Curr Dev Nutr 2024; 8:102088. [PMID: 38419834 PMCID: PMC10897853 DOI: 10.1016/j.cdnut.2024.102088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 01/11/2024] [Accepted: 01/24/2024] [Indexed: 03/02/2024] Open
Abstract
Background Information on salt consumption patterns is needed to inform the need for and design of salt reduction strategies. Objectives In northern Ghana, this study aimed to estimate household consumption of salt, including salt from bouillon, and compare (estimated) women and children's salt intake to global recommendations; to estimate the proportion of salt consumed from bouillon; and to identify factors, including knowledge, attitudes, and practices, associated with household salt consumption. Methods Employing mixed-methods methodology, we conducted a pilot survey (n = 369 households enrolled) and focus group discussions (FGDs; n = 20) in Tolon and Kumbungu districts (14 urban, 14 rural clusters) (clinicaltrials.gov registry: NCT04632771). Households reported purchases of discretionary salt (DS, "table salt") and bouillon cubes. DS and total salt (TS; DS+salt from bouillon) consumption for women (15-49 y) and children (2-5 y) were estimated using the Adult Male Equivalent method and compared with global recommendations (<5 g/d women; <3.75 g/d children). Women's salt intake was also predicted from urinary sodium excretion (INTERSALT equation). Associations between DS and TS consumption, as well as household and women's characteristics, were tested with minimally adjusted and multivariable linear mixed-effects models. Qualitative FGD themes were generated using the Framework Method. Results From household purchase data, estimated TS consumption exceeded global recommendations for 44% of children [median: 2.9 (IQR: 1.9, 5.2) g/d] and 60% of women [6.0 (4.0, 10.2) g/d]; 35% of children and 50% of women exceeded recommendations from DS alone. Bouillon contributed <25% of households' TS consumption. Few characteristics were associated with DS or TS consumption. Salient qualitative themes that shaped salt consumption behaviors included salt's ubiquity as a seasoning, key household members' influence on food procurement and preparation, and perceptions about health. Conclusions Purchase data suggest salt consumption among women and children exceeds recommendations, even when excluding salt from bouillon; food prepared outside the home likely further contributes. Salt reduction interventions may be warranted in this context.
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Affiliation(s)
- Jennie N Davis
- University of California, Department of Nutrition, Institute for Global Nutrition, Davis, CA, United States
| | - Sika M Kumordzie
- University of California, Department of Nutrition, Institute for Global Nutrition, Davis, CA, United States
| | - Charles D Arnold
- University of California, Department of Nutrition, Institute for Global Nutrition, Davis, CA, United States
| | - K Ryan Wessells
- University of California, Department of Nutrition, Institute for Global Nutrition, Davis, CA, United States
| | - Kania W Nyaaba
- University of Ghana, Department of Nutrition and Food Science, Legon, Accra, Ghana
| | - Katherine P Adams
- University of California, Department of Nutrition, Institute for Global Nutrition, Davis, CA, United States
| | - Xiuping Jenny Tan
- University of California, Department of Nutrition, Institute for Global Nutrition, Davis, CA, United States
| | - Emily Becher
- University of California, Department of Nutrition, Institute for Global Nutrition, Davis, CA, United States
| | - Stephen A Vosti
- University of California, Department of Agriculture and Resource Economics, Institute for Global Nutrition, Davis, CA, United States
| | - Seth Adu-Afarwuah
- University of Ghana, Department of Nutrition and Food Science, Legon, Accra, Ghana
| | - Reina Engle-Stone
- University of California, Department of Nutrition, Institute for Global Nutrition, Davis, CA, United States
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Kenao TS, Sossa JC, Paraiso MN, Belo M, Sopoh GE, Tchankoni KM, Agueh V. Sodium, potassium food intake and global cardiovascular risks in Togo. J Public Health Afr 2023; 14:2301. [PMID: 37441118 PMCID: PMC10334439 DOI: 10.4081/jphia.2023.2301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 09/04/2022] [Indexed: 07/15/2023] Open
Abstract
Objectives To assess urinary sodium/potassium intake and identify its links with global cardiovascular risk (GCVR) according to the WHOPEN approach to WHO/ISH (International High Blood Pressure Society). Methods It was a cross-sectional and analytical study that took place from July 6, 2020, to September 17, 2021, in Togo, in the Aneho, Notse and Dapaong localities. It focused on 400 adults selected by sampling. The analysis of two urine samples was done. Cardiovascular risk scores were determined from specific graphs that take into account age, gender, systolic blood pressure, diabetes status, and smoking behavior. Results Among the 400 respondents, 49% lived in rural areas. The average age was 41 (30; 51) years. The average sodium and potassium intakes were respectively 3.2 g (1.04-5.99) or 7.95 g of salt and 1.4 g (1.89-5.62) per day. The risk of excessive sodium intake was 2.39 times higher in urban areas than in rural ones (P=0.049). Residing in rural areas was associated with high potassium intakes compared to urban ones [OR=3,2 IC (1.89-5.62)]. Thirteen percent (13%) of respondents were likely to develop at least a deadly or non-deadly cardiovascular disease in the next 10 years 'time, of whom 5% present a high risk. Excessive sodium intake increases by 2.10 times the risk of a deadly cardiovascular disease occurrence. Conclusions Sodium intakes are high while potassium intakes are low with a subsequent GCVR in the three cities. Sodium intakes were associated with GCVR. It is necessary to take steps to reduce excessive sodium intake and improve potassium intake.
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Affiliation(s)
- Tchasso Serge Kenao
- Health Promotion Department, Regional Institute of Public Health, University of Abomey-Calavi, Benin
| | - Jerome Charles Sossa
- Health Promotion Department, Regional Institute of Public Health, University of Abomey-Calavi, Benin
| | - Moussiliou Noël Paraiso
- Health Promotion Department, Regional Institute of Public Health, University of Abomey-Calavi, Benin
| | - Mofou Belo
- University of Lomé, Faculty of Medicine, Togo
| | - Ghislain Emmanuel Sopoh
- Department of Policy and Health Policy, Regional Institute of Public Health, University of Abomey-Calavi, Benin
| | | | - Victoire Agueh
- Health Promotion Department, Regional Institute of Public Health, University of Abomey-Calavi, Benin
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Zhang X, Zhang F, Li Q, Feng C, Teng W. Iodine nutrition and papillary thyroid cancer. Front Nutr 2022; 9:1022650. [PMID: 36337631 PMCID: PMC9631789 DOI: 10.3389/fnut.2022.1022650] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 09/30/2022] [Indexed: 09/19/2023] Open
Abstract
Thyroid cancer (TC) is the most frequent endocrine malignancy. The incidence of TC, especially papillary thyroid carcinoma (PTC), has continued to rise all over the world during the past few years, for reasons that are not entirely clear. Though the phenomenon of overdiagnosis is occurring, it is not the sole driver of the substantial increase in incidence. Lifestyle, environmental factors, or complications are considered to be potential risk factors. Among these factors, iodine is a micronutrient that is vital to thyroid function. The effect of iodine intake on PTC has been controversial for many years and the epidemiological or experimental studies provided diametrically opposite conclusions. Combining all these studies, we found that iodine nutrition may affect the overall prevalence, distribution of the histological types, and clinicopathological aggressiveness of TC, especially PTC. However, the available evidence is poor due to the impact of various internal and external related factors. Therefore, this article sums up available results from both epidemiological and experimental studies, future studies are also warranted to expound on the relationship between overall PTC prevalence and iodine intake.
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Nista F, Bagnasco M, Gatto F, Albertelli M, Vera L, Boschetti M, Musso N, Ferone D. The effect of sodium restriction on iodine prophylaxis: a review. J Endocrinol Invest 2022; 45:1121-1138. [PMID: 35079975 DOI: 10.1007/s40618-022-01749-y] [Citation(s) in RCA: 3] [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] [Received: 12/20/2021] [Accepted: 01/16/2022] [Indexed: 01/06/2023]
Abstract
PURPOSE Sodium is essential to life. However, its dietary excess is detrimental to the cardiovascular system, and sodium restriction is a crucial step in cardiovascular prevention. Iodine deficiency has been fought worldwide for decades, and substantial success has been achieved introducing the use of iodine-enriched salt. Nevertheless, areas of iodine deficiency persist around the world, both in developing and industrialized countries, and a major concern affecting dietary sodium reduction programs is represented by a possible iodine intake deficiency. There are substantial differences in the source of alimentary iodine among countries, such as iodized salt added, household tap water, seafood, or salt employed in packaged food. It is clear that a sodium-restricted diet can induce differences in terms of iodine intake, depending on the country considered. Moreover, iodine status has undergone relevant changes in many countries in the last years. METHODS Systematic review of literature evidence about the possible effects of sodium restriction on population iodine status. RESULTS To date, the available results are conflicting, depending on country, salt iodization policy, as well as time frame of data collection. However, to ensure an optimal iodine supply by salt fortification, without exceeding the current recommendation by World Health Organization for salt intake, seems to be an achievable goal. CONCLUSION A balanced approach may be obtained by an adequate iodine concentration in fortified salt and by promoting the availability of iodized salt for household consumption and food industry use. In this scenario, updated prospective studies are strongly needed.
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Affiliation(s)
- F Nista
- Endocrinology Unit, Department of Internal Medicine and Center of Excellence for Biomedical Research, University of Genoa, Genoa, Italy
| | - M Bagnasco
- Department of Internal Medicine and Medical Specialties, President-elect of the Italian Thyroid Association, University of Genoa, Genoa, Italy
| | - F Gatto
- Endocrinology Unit, IRCCS Ospedale Policlinico San Martino, 16132, Genoa, Italy.
| | - M Albertelli
- Endocrinology Unit, Department of Internal Medicine and Center of Excellence for Biomedical Research, University of Genoa, Genoa, Italy
| | - L Vera
- Endocrinology Unit, IRCCS Ospedale Policlinico San Martino, 16132, Genoa, Italy
| | - M Boschetti
- Endocrinology Unit, Department of Internal Medicine and Center of Excellence for Biomedical Research, University of Genoa, Genoa, Italy
| | - N Musso
- Endocrinology Unit, IRCCS Ospedale Policlinico San Martino, 16132, Genoa, Italy
| | - D Ferone
- Endocrinology Unit, Department of Internal Medicine and Center of Excellence for Biomedical Research, University of Genoa, Genoa, Italy
- Endocrinology Unit, IRCCS Ospedale Policlinico San Martino, 16132, Genoa, Italy
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Matthias D, McDonald CM, Archer N, Engle-Stone R. The Role of Multiply-Fortified Table Salt and Bouillon in Food Systems Transformation. Nutrients 2022; 14:nu14050989. [PMID: 35267964 PMCID: PMC8912775 DOI: 10.3390/nu14050989] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 02/18/2022] [Accepted: 02/23/2022] [Indexed: 01/09/2023] Open
Abstract
Our global food system lacks the critically needed micronutrients to meet the daily requirements of the most at-risk populations. Diets also continue to shift toward unhealthy foods, including the increased intake of salt. While most countries exceed the WHO’s recommended levels, sodium does play an essential physiological role. Table salt and other salt-containing condiments, such as bouillon, also have cultural importance, as they are used to enhance the flavor of foods cooked at home. Given their universal consumption across income classes and both urban and rural populations, these condiments are an integral part of the food system and should, therefore, be part of its transformation. Fortification of salt and salt-containing condiments can play a catalytic role in the delivery of population-wide nutritional and health benefits. With relatively consistent levels of intake across the population, these condiments hold high potential for delivering micronutrients beyond iodine while also reducing concerns related to high micronutrient intake, particularly so in countries where the industries are relatively consolidated. As a flexible and complementary strategy to an evolving food system, fortification levels can also be adjusted over time to ensure micronutrient delivery targets continue to be achieved as the system improves, whether through lower intakes of sodium in line with WHO recommendations, enhanced consumption of nutrient-dense foods, and/or broader adoption of biofortified crops. Future areas of innovation are required to realize this vision, including developing affordable salt substitutes to meet cost requirements of consumers in low-and middle-income countries, improving the stability and bioavailability of the micronutrients in condiments so that delivery targets can be reached without affecting sensory attributes, and the development of efficient systems for monitoring population intake and micronutrient status to inform fortification program design and management. Rather than being considered antithetical to the transformation, multiply-fortified salt and bouillon can strengthen our ability to meet the cultural, sensory, nutritional, and health needs of an evolving food system.
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Affiliation(s)
- Dipika Matthias
- Bill & Melinda Gates Foundation, Seattle, WA 98109, USA
- Correspondence:
| | - Christine M. McDonald
- Departments of Pediatrics, and Epidemiology and Biostatistics, University of California, San Francisco, CA 94143, USA;
- Department of Nutrition and Institute for Global Nutrition, University of California, Davis, CA 95616, USA;
| | - Nicholas Archer
- CSIRO Health and Biosecurity, North Ryde, Sydney 2113, Australia;
| | - Reina Engle-Stone
- Department of Nutrition and Institute for Global Nutrition, University of California, Davis, CA 95616, USA;
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Ngounda J, Baumgartner J, Nel M, Walsh CM. Iodine status of pregnant women residing in the urban Free State Province of South Africa is borderline adequate: The NuEMI study. Nutr Res 2022; 98:18-26. [DOI: 10.1016/j.nutres.2021.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 11/30/2021] [Accepted: 12/02/2021] [Indexed: 10/19/2022]
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Arns-Glaser L, Zandberg L, Assey VD, Baumgartner J, Abdallah F, Galetti V, Dary O, Zimmermann MB, Andersson M. Seasonal effects on urinary iodine concentrations in women of reproductive age: An observational study in Tanzania and South Africa. Am J Clin Nutr 2022; 115:298-309. [PMID: 34601579 DOI: 10.1093/ajcn/nqab327] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 09/24/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Iodine intake in populations is usually assessed by measuring urinary iodine concentrations (UICs) in spot samples. Hot climate conditions may reduce urine volume, thus leading to overestimations of UIC and thereby masking inadequate iodine intake. OBJECTIVES We investigated the effects of season on UICs in 2 populations exposed to high-temperature climates. METHODS In this observational study, we examined women (18-49 years) in Tanzania (ncold = 206; nhot = 179) and South Africa (ncold = 157; nhot = 126) during cold and hot seasons. From each woman in both seasons, we obtained two 24-hour urine collections and 2 spot urine samples, as well as salt, water, and cow's milk samples. We measured the urine volume, UIC, and urinary creatinine concentration (UCC). The 24-hour urinary iodine excretion (UIE) was calculated and used to estimate the iodine intake. We used linear mixed-effects models to test for differences between seasons. RESULTS In Tanzanian women, we observed no seasonal effect on the urine volume, 24-hour UIE, 24-hour UIC, spot UIC, spot UIC:UCC ratio, or salt iodine concentration. In South African women, the median 24-hour urine volume was 1.40 L (IQR, 0.96-2.05 L) in the winter and 15% lower in the summer (P < 0.001). The median 24-hour UIE was 184 µg/day (IQR, 109-267 µg/day) in the winter and 34% lower in the summer (P < 0.001), indicating a lower iodine intake. As a result, UICs did not significantly differ between seasons in 24-hour collections and spot samples, whereas the spot UIC:UCC ratio differed by 21% (P < 0.001) and reflected the lower iodine intake. In both study populations, the within- and between-person variabilities in urine volume, 24-hour UICs, and spot UICs were higher than the variability between seasons. CONCLUSIONS Spot UIC may slightly overestimate the iodine intake in hot temperatures due to concentrated urine, and methods to correct for urine volume may be considered. Local seasonal differences in iodine intakes may also occur in some populations. This trial was registered at http://www.clinicaltrials.gov as NCT03215680.
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Affiliation(s)
- Leonie Arns-Glaser
- Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Lizelle Zandberg
- Centre of Excellence for Nutrition, Faculty of Health Sciences, North-West University, Potchefstroom, South Africa
| | - Vincent D Assey
- Nutrition Services Section Ministry of Health, Community Development, Gender, Elderly and Children, Dar es Salaam, Tanzania.,Iodine Global Network, Ottawa, Canada
| | - Jeannine Baumgartner
- Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.,Centre of Excellence for Nutrition, Faculty of Health Sciences, North-West University, Potchefstroom, South Africa
| | - Fatma Abdallah
- Iodine Global Network, Ottawa, Canada.,Tanzania Food and Nutrition Centre, Dar es Salaam, Tanzania
| | - Valeria Galetti
- Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Omar Dary
- Division of Nutrition and Environmental Health, Office of Maternal and Child Health and Nutrition, Bureau for Global Health, United States Agency for International Development, Washington, DC, USA
| | - Michael B Zimmermann
- Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.,Iodine Global Network, Ottawa, Canada
| | - Maria Andersson
- Iodine Global Network, Ottawa, Canada.,Nutrition Research Unit, Children's Research Centre, University Children's Hospital Zurich, Zürich, Switzerland
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