The Long Term Impact of Micronutrient Supplementation during Infancy on Cognition and Executive Function Performance in Pre-School Children

Brain growth and development are critically dependent on several micronutrients. During early development cellular activity may be sensitive to micronutrient deficiencies, however the evidence from human studies is equivocal. The objective of this study was to examine the long-term cognitive and social-emotional effects of multiple micronutrient supplementation compared with iron supplementation alone, administered during infancy. This study was a follow-up to an initial randomized, double-blind controlled trial (RCT) in 2010 in which 902 infants, aged 6-17 months, from Lima, Peru, were given daily supplements of either iron (Fe) or multiple micronutrients (MMN) including zinc (451 in each group). The supplementation period for both groups was six months. In 2012, a subsample of 184 children from the original cohort (now aged 36-48 months) was randomly selected to participate in a follow-up trial and was assessed for intelligence, working memory, inhibition, and executive function. The tests showed no significant differences between the supplementation groups though there were some gender differences, with girls displaying higher scores than boys across both groups on the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) Verbal IQ sentences subtest, the Day-Night cognitive test and on the Brief Infant-Toddler Social Emotional Assessment (BITSEA) social competency, and boys scoring higher than girls in problem behaviour. The results indicate that MMN supplementation had no long term additional effects on cognitive function compared with iron supplementation alone. The timing of supplement administration for maximum impact on a child's cognitive development requires further investigation

The relationship between zinc intake and growth in children aged 1-8 years: a systematic review and meta-analysis

BACKGROUND/OBJECTIVES: It is estimated that zinc deficiency affects 17% of the world's population, and because of periods of rapid growth children are at an increased risk of deficiency, which may lead to stunting. This paper presents a systematic review and meta-analysis of the randomised controlled trials (RCTs) that assess zinc intake and growth in children aged 1–8 years. This review is part of a larger systematic review by the European Micronutrient Recommendations Aligned Network of Excellence that aims to harmonise the approach to setting micronutrient requirements for optimal health in European populations (www.eurreca.org). SUBJECT/METHODS: Searches were performed of literature published up to and including December 2013 using MEDLINE, Embase and the Cochrane Library databases. Included studies were RCTs in apparently healthy child populations aged from 1 to 8 years that supplied zinc supplements either as capsules or as part of a fortified meal. Pooled meta-analyses were performed when appropriate. RESULTS: Nine studies met the inclusion criteria. We found no significant effect of zinc supplementation of between 2 weeks and 12 months duration on weight gain, height for age, weight for age, length for age, weight for height (WHZ) or WHZ scores in children aged 1–8 years. CONCLUSIONS: Many of the children in the included studies were already stunted and may have been suffering from multiple micronutrient deficiencies, and therefore zinc supplementation alone may have only a limited effect on growth

The relationship between zinc intake and serum/plasma zinc concentration in adults: a systematic review and dose–response meta-analysis by the EURRECA Network

Dietary zinc recommendations vary widely across Europe due to the heterogeneity of pproaches used by expert panels. Under the EURRECA consortium a protocol was designed to systematically review and undertake meta-analyses of research data to create a database that includes “best practice” guidelines which can be used as a resource by future panels when setting micronutrient recommendations. As part of this process, the objective of the present study was to undertake a systematic review and meta-analysis of previously published data describing the relationship between zinc intake and status in adults. Searches were performed of literature published up to February 2010 using MEDLINE, Embase, and Cochrane Library. Data extracted included population characteristics, dose of zinc, duration of study, dietary intake of zinc, and mean concentration of zinc in plasma or serum at the end of the intervention period. An intake-status regression coefficient was estimated for each individual study, and pooled meta-analysis undertaken. The overall pooled for zinc supplementation on serum/plasma zinc concentrations from RCTs and observational studies was 0.08 (95% CI 0.05, 0.11; p<0.0001; I2 84.5%). An overall of 0.08 means that for every doubling in zinc intake, the difference in zinc serum or plasma concentration is (20.08 = 1.06), which is 6%. Whether the dose-response relationship, as provided in this paper, could be used as either qualitative or quantitative evidence to substantiate the daily zinc intake dose necessary to achieve normal or optimal levels of biomarkers for zinc status, remains a matter of discussion

Effect of zinc intake on growth in infants: A meta-analysis

A systematic review and meta-analysis of available randomized controlled trials (RCTs) was conducted to evaluate the effect of zinc (Zn) intake on growth in infants. Out of 5500 studies identified through electronic searches and reference lists, 19 RCTs were selected after applying the exclusion/inclusion criteria. The influence of Zn intake on growth was considered in the overall meta-analysis. Other variables were also taken into account as possible effect modifiers: doses of Zn intake, intervention duration, nutritional status, and risk of bias. From each select growth study, final measures of weight, length, mid upper arm circumference (MUAC), head circumference, weight for age z-score (WAZ), length for age z-score (LAZ), and weight for length z-score (WLZ) were assessed. Pooled β and 95% confidence interval (CI) were calculated. Additionally, we carried out a sensitivity analysis. Zn intake was not associated with weight, length, MUAC, head circumference, and LAZ in the pooled analyses. However, Zn intake had a positive and statistically effect on WAZ (β = 0.06; 95%CI 0.02 to 0.10) and WLZ (β = 0.05; 95%CI 0.01 to 0.08). The dose–response relationship between Zn intake and these parameters indicated that a doubling of Zn intake increased WAZ and WLZ by approximately 4%. Substantial heterogeneity was present only in length analyses (I2 = 45%; p = 0.03). Zn intake was positively associated with length values at short time (four to 20 weeks) (β = 0.01; CI 95% 0 to 0.02) and at medium doses of Zn (4.1 to 8 mg/day) (β = 0.003; CI 95% 0 to 0.01). Nevertheless, the effect magnitude was small. Our results indicate that Zn intake increases growth parameters of infants. Nonetheless, interpretation of these results should be carefully considered

Development and Sustainability of National Food Composition Databases for use in Dietary Monitoring and Public Health Nutrition in the Eastern Mediterranean Region

Background:Similar to Western Countries, the Eastern Mediterranean Region (EMR) also presents major public health issues associated with the increased consumption of sugar, fat (saturated fatty acids, trans fatty acids), salt. Therefore, one of the policies of the World Health Organization’s (WHO) EMRO is to reduce the intake of these, to address the risk of obesity and non-communicable diseases such as diabetes, cardiovascular disease and cancer. In order to do this, access to updated, standardized, harmonized food composition data (FCD) is essential. Aims: Objectives within this Medical Research Council GCRF project, working jointly with WHO–EMRO, are to assess the status of national FCD and to provide training and capacity development in the use of improved standardized methodologies to update FCD as well as dietary intake methods, use of suitable biomarkers of nutritional value and to determine health outcomes in the low- and middle-income countries (LMIC) of this region. By identifying specific regional needs for FCD compilation, detailed training workshops can be developed to enable the production of vital high-quality harmonised data in the EMR including: Iran, Iraq, Pakistan, Kuwait, Tunisia, Morocco, Sudan, Egypt, Jordan together with Mauritania. This capacity building will lead to the development and sustainability of up-to-date national and regional FCD for use in dietary monitoring assessment in food and nutrient intakes. Methods: Training needs were identified, and short-term scientific missions organized for researchers via training, knowledge exchange workshops and short-term exchange of researchers. Training at CAPNUTRA (Serbia) and INNTA (Tunisia) included the use of improved standardized methodologies for food composition and food intake for 7 EMR countries leading to development of national FCD, enabling upload onto the EuroFIR data platform. A 3-week training course on analytical methods was carried out at INSA (Portugal) for analysts from Egypt, Jordan and Sudan. Key findings: A total of 45 participants from 13 countries including 10 EMR and 3 invited West African countries attended 5 workshops and training exchanges. Training topics included: value documentation and quality assessment; food composition data tools (Food Composition And System Environment (FoodCASE), Diet assess and Plan (DAP), Nutritics; food classification and description of composite dishes, recipe calculation approaches; use of yield and retention factors; EuroFIR e-learning tools and case studies; laboratory food analysis (vitamins A, B1, B2, C, D2, D3 and E, fatty acids, amino acids, minerals, fibre); quality management system; food metrology principles; validation of chromatographic methods; and food label legislation. 6 countries have imported their FCD, as open access, into the EuroFIR FoodEXplorer platform. The WHO-EMRO jointly with MRC GCRF project funded and mobilized research institutions in over 10 countries, with more focus on identifying traditional dishes and micronutrients. Conclusions and project Implications: The use of improved standardized methodologies for food composition and dietary intake will produce robust measurements that will reinforce dietary monitoring and policy in LMIC. The capacity building from this project has led to searchable national food composition data from developing/emerging countries being made available in an open access form for the first time. WHO-EMRO, is funding further updates of FCD tables in Jordan, Lebanon, Oman, Sudan, Tunisia, Morocco, Pakistan, Iran Egypt, and UAE, with the focus on identifying TFA, SFA, salt and sugar in addition to micronutrients.Project supported by Global Challenges Research Funds (UK) and Medical Research Council (MR/R019576/1), is grateful to WHO EMRO.info:eu-repo/semantics/publishedVersio

Development and Sustainability of Eastern Mediterranean Region and South African National Food Composition Databases

Introduction: The World Health Organization’s (WHO)-Eastern Mediterranean Region Office (EMRO) aims to reduce the consumption of sugar, fat (saturated fatty acids, trans fatty acids) and salt; and decrease the risk of obesity and non-communicable diseases in the Eastern Mediterranean Region (EMR). To address this Quadram Institute Bioscience is working jointly with WHO-EMRO in providing training and capacity development to national experts, leading to standardized, harmonized, comprehensive, open access Food Composition Data (FCD) to underpin food and nutrition programs and policies in these low- and middle-income countries (LMIC). Materials and Methods: By identifying specific regional needs for FCD compilation, detailed training workshops were developed to enable the production of vital high-quality harmonised data in the EMR including: Iran, Iraq, Pakistan, Kuwait, Tunisia, Morocco, Sudan, Egypt, and Jordan. Training on standardized methodologies for food composition and dietary intake methods, biomarkers, analytical methods and FCD tools were provided by experts from UK, Serbia, Portugal and WHO-EMRO, via knowledge exchange workshops and short-term training exchange of researchers. Results: A total of 45 FCD expert compilers from 13 countries attended 2 workshops and 3 training exchanges. Knowledge transfer consisted of: value documentation; quality assessment; online food composition data tools; food classification and description of composite dishes; recipe calculation; yield and retention factors; and laboratory food analysis (vitamins A, B1, B2, C, D2, D3 and E, fatty acids, amino acids, minerals, fibre). FCD from 6 countries was standardized using the EuroFIR data template and Theasuri (standardised vocabularies). The final datasets from Iran, Iraq, Pakistan, Kuwait, Tunisia and Morocco were made available via FoodExplorer an innovative interface for FCD which allows users to search information from food composition data simultaneously across many countries. Discussion: The use of improved standardized methodologies for food composition and dietary intake will produce robust measurements that will reinforce dietary monitoring and policy in LMIC. The capacity building from this project has led to searchable national food composition data from LMIC being made available as open access form for the first time. WHO-EMRO, is funding further updates of FCD tables in Jordan, Lebanon, Oman, Sudan, Tunisia, Morocco, Pakistan, Iran, Egypt, and UAE, with the focus on identifying TFA, SFA, salt and sugar in addition to micronutrients.Project supported by Global Challenges Research Funds (UK) and Medical Research Council (MR/R019576/1), is grateful to WHO EMRO.info:eu-repo/semantics/publishedVersio

Dietary zinc intake and whole blood zinc concentration in subjects with type 2 diabetes versus healthy subjects: A systematic review, meta-analysis and meta-regression

The aim of this systematic review, meta-analysis and meta-regression was to examine the relationship between type 2 diabetes mellitus (T2DM) and concentration of zinc in whole blood, as well as dietary zinc intake. Searches were performed using Ovid MEDLINE, Embase (Ovid) and The Cochrane Library (CENTRAL). Observational studies conducted on diabetic and healthy adults, with data on dietary zinc intake and/or concentration of zinc in whole blood, were selected. The search strategy yielded 11,150 publications and the manual search 6, of which 11 were included in the meta-analyses. Mean difference (MD) and 95% confidence interval (CI), were calculated using the generic inverse-variance method with random-effects models. Heterogeneity was assessed by the Cochran Q-statistic and quantified by the I2 statistic. Meta-regressions and stratified analysis were used to examine whether any covariate had influence on the results. The pooled MD for the dietary zinc intake meta-analysis was −0.40 (95% CI: −1.59 to 0.79; I2 = 61.0%). Differences between diabetic and non-diabetic subjects became significant in the presence of complications associated with diabetes (MD = −2.26; 95% CI: −3.49 to −1.02; I2 = 11.9%). Meta-regression showed that for each year since the diagnosis of diabetes the concentration of zinc in whole blood decreased in diabetic patients regarding healthy controls [MD (concentration of zinc in blood) = 732.61 + (−77.88303) × (duration of diabetes in years)], which is not generally explained by a lower intake of zinc

Zinc Intake and Status and Risk of Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Zinc could have a protective role against type 2 diabetes mellitus (T2DM). This systematic review and meta-analysis aimed to evaluate the association between dietary, supplementary, and total zinc intake, as well as serum/plasma and whole blood zinc concentration, and risk of T2DM. Observational studies, conducted on cases of incident diabetes or T2DM patients and healthy subjects that reported a measure of association between zinc exposure and T2DM, were selected. Random effects meta-analyses were applied to obtain combined results. Stratified meta-analyses and meta-regressions were executed to assess sources of heterogeneity, as well as the impact of covariates on the findings. From 12,136 publications, 16 studies were selected. The odds ratio (OR) for T2DM comparing the highest versus lowest zinc intake from diet was 0.87 (95% CI: 0.78–0.98). Nevertheless, no association between supplementary or total zinc intake from both diet and supplementation, and T2DM was observed. A direct relationship was found between serum/plasma zinc levels and T2DM (OR = 1.64, 95% CI: 1.25–2.14). A moderately high dietary zinc intake, in relation to the Dietary Reference Intake, could reduce by 13% the risk of T2DM, and up to 41% in rural areas. Conversely, elevated serum/plasma zinc concentration was associated with an increased risk of T2DM by 64%, suggesting disturbances in zinc homeostasis

The Relationship between Zinc Intake and Serum/Plasma Zinc Concentration in Children: A Systematic Review and Dose-Response Meta-Analysis

Recommendations for zinc intake during childhood vary widely across Europe. The EURRECA project attempts to consolidate the basis for the definition of micronutrient requirements, taking into account relationships among intake, status and health outcomes, in order to harmonise these recommendations. Data on zinc intake and biomarkers of zinc status reported in randomised controlled trials (RCTs) can provide estimates of dose-response relationships which may be used for underpinning zinc reference values. This systematic review included all RCTs of apparently healthy children aged 1–17 years published by February 2010 which provided data on zinc intake and biomarkers of zinc status. An intake-status regression coefficient was calculated for each individual study and calculated the overall pooled and SE using random effects meta-analysis on a double log scale. The pooled dose-response relationship between zinc intake and zinc status indicated that a doubling of the zinc intake increased the serum/plasma zinc status by 9%. This evidence can be utilised, together with currently used balance studies and repletion/depletion studies, when setting zinc recommendations as a basis for nutrition policies