A micronutrient-fortified seasoning powder reduces morbidity and improves short-term cognitive function, but has no effect on anthropometric measures in primary school children in northeast Thailand: a randomized controlled trial

Quality and Quantity of School Lunch in Nanjing: Based on Data from the Sunshine Restaurant Supervision Platform

School lunch plays an important role in children's healthy growth. Previous investigations revealed many problems with school lunches, including unreasonable dietary structure and insufficient micronutrients. This study aimed to assess the dietary structure and nutritional quality of lunches in Nanjing primary and middle schools. A stratified cluster random sampling method was used to select 44 schools that supply lunch in 12 districts in Nanjing, with two primary and two middle schools in each district. Twenty-four primary and twenty middle schools were selected. The Mann-Whitney U test was used to explore the influencing factors. Findings revealed a serious shortage of milk and fruit in school lunches; supply of eggs, fish, shrimp, and shellfish was less than half of the recommended quantity; livestock and poultry supply exceeded the recommended level by over four times. Energy and nutrition intake were suboptimal. Provision of energy, carbohydrates, vitamins (A, B1, B2, and C), calcium, and iron in urban primary schools was significantly higher than that in non-urban primary schools. The same pattern of significantly higher nutrients was equally seen in urban middle schools compared with non-urban middle schools, indicating that food supply was affected by regional economies. Therefore, it is urgent to improve the quality of lunches, with a particular focus on those in non-urban areas.

Fortification of condiments and seasonings with iron for preventing anaemia and improving health

BACKGROUND

Anaemia affects approximately 1.8 billion people worldwide; over 60% of anaemia cases globally are due to iron deficiency (ID). Iron deficiency and anaemia contribute to the global burden of disease and affect physical and cognitive development in children, and work productivity and economic well-being in adults. Fortification of food with iron, alone or in combination with other nutrients, is an effective intervention to control ID. Condiments and seasonings are ideal food vehicles for iron fortification in countries where they are commonly used.

OBJECTIVES

To determine the effects and safety of condiment and seasoning fortification with iron alone or iron plus other micronutrients on iron deficiency, anaemia, and health-related outcomes in the general population.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, and other databases up to 24 January 2023. We also searched the International clinical trials registry platform (ICTRP) for any ongoing trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) (randomisation at individual or cluster level), non-randomised controlled trials, interrupted time series with at least three measure points both before and after intervention, and controlled before-after studies. Participants were populations of any age (including pregnant women), from any country, excluding those with critical illness or severe co-morbidities. We included interventions in which condiments or seasonings have been fortified with any combination of iron and other vitamins and minerals, irrespective of the fortification technology used.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened and assessed the eligibility of studies. Disagreements were resolved through discussion or input from a third review author. Two review authors extracted the data and assessed the risk of bias in all the included studies. We followed the methods laid out by Cochrane and used GRADE criteria for assessing certainty of the evidence.

MAIN RESULTS

Our search identified 15,902 records after removal of duplicates. We included 16 studies with 20,512 participants (18,410 participants after adjusting for clustering effects). They were all carried out in upper-middle- and lower-middle-income countries. Three studies were controlled before-after studies, one was non-randomised trial, and 12 were RCTs (including three cluster RCTs). Six studies took place in schools; seven in communities; and one each in a nursery/kindergarten, tea estate, and factory. Three studies involved only women, one study involved both women and their children, and all other studies focused on children and/or adolescents. Nine studies used salt as a vehicle for iron fortification, three used fish sauce, two used soy sauce, one used curry powder, and one a "seasoning powder". The dose of iron received by participants ranged from 4.4 mg to 55 mg/day. The sample sizes in the trials ranged from 123 to 14,398, and study durations ranged from three months to two years. Twelve RCTs contributed data for meta-analysis. Six trials compared iron-fortified condiments versus the unfortified condiment, and six trials provided data comparing iron fortification in combination with other micronutrients versus the same condiment with other micronutrients, but no added iron. In one trial, the fortificant contained micronutrients that may have affected the absorption of iron. Overall no studies were assessed as having a low risk of bias. All included studies were assessed to have a high overall risk of bias, with the most concerns being around allocation concealment, blinding, and random sequence generation. There was very high heterogeneity amongst studies in almost all examined outcomes. Condiments/seasonings fortified with iron versus unfortified condiments/seasonings We are uncertain about whether consuming condiments/seasonings fortified with iron in comparison to the same unfortified condiment reduces anaemia at the end of intervention (risk ratio (RR) 0.34, 95% confidence interval (CI) 0.18 to 0.65; 2328 participants; 4 studies; very low-certainty of evidence). We are uncertain about whether consuming iron-fortified condiments increases haemoglobin concentrations (mean difference (MD) 6.40 (g/L), 95% CI -0.62 to 13.41; 2808 participants; 5 studies; very low-certainty evidence). Fortification of condiments/seasonings with iron probably slightly reduces ID (RR 0.33, 95% CI 0.11 to 1.01; 391 participants; 2 studies; moderate-certainty evidence). We are uncertain about whether fortification with iron increases ferritin concentration (MD 14.81 (µg/L), 95% CI 5.14 to 24.48; 4459 participants; 6 studies; very low-certainty evidence). Condiments/seasonings fortified with iron plus other micronutrients versus condiments/seasonings fortified with other micronutrients except iron Consuming condiments/seasonings fortified with iron plus other micronutrients may reduce anaemia (RR 0.59, 95% CI 0.40 to 0.89; 1007 participants; 4 studies; low-certainty evidence). We are uncertain about whether fortification of condiments/seasonings with iron plus other micronutrients will improve haemoglobin concentration (MD 6.22 g/dL, 95% CI 1.60 to 10.83; 1270 participants; 5 studies; very low-certainty evidence). It may reduce ID (RR 0.36, 95% CI 0.19 to 0.69; 1154 participants; 4 studies; low-certainty evidence). We are uncertain about whether fortification with iron plus other micronutrients improves ferritin concentration (MD 10.63 µg/L, 95% CI 2.40 to 18.85; 1251 participants; 5 studies; very low -certainty evidence). Condiments/seasonings fortified with iron versus no intervention No trial reported data on this comparison. No studies reported adverse effects. Funding sources do not appear to have distorted the results in any of the assessed trials.

AUTHORS' CONCLUSIONS

We are uncertain whether consuming iron-fortified condiments/seasonings reduces anaemia, improves haemoglobin concentration, or improves ferritin concentration. It may reduce ID. Findings about ferritin should be interpreted with caution since its concentrations increase during inflammation. Consuming condiments/seasonings fortified with iron plus other micronutrients may reduce anaemia, and we are uncertain whether this will improve haemoglobin concentration or ferritin concentration. More studies are needed to determine the true effect of iron-fortified condiments/seasonings on preventing anaemia and improving health. The effects of this intervention on other health outcomes like malaria incidence, growth and development are unclear.

Effects of iron deficiency and iron supplementation at the host-microbiota interface: Could a piglet model unravel complexities of the underlying mechanisms?

Iron deficiency is the most prevalent human micronutrient deficiency, disrupting the physiological development of millions of infants and children. Oral iron supplementation is used to address iron-deficiency anemia and reduce associated stunting but can promote infection risk since restriction of iron availability serves as an innate immune mechanism against invading pathogens. Raised iron availability is associated with an increase in enteric pathogens, especially Enterobacteriaceae species, accompanied by reductions in beneficial bacteria such as Bifidobacteria and lactobacilli and may skew the pattern of gut microbiota development. Since the gut microbiota is the primary driver of immune development, deviations from normal patterns of bacterial succession in early life can have long-term implications for immune functionality. There is a paucity of knowledge regarding how both iron deficiency and luminal iron availability affect gut microbiota development, or the subsequent impact on immunity, which are likely to be contributors to the increased risk of infection. Piglets are naturally iron deficient. This is largely due to their low iron endowments at birth (primarily due to large litter sizes), and their rapid growth combined with the low iron levels in sow milk. Thus, piglets consistently become iron deficient within days of birth which rapidly progresses to anemia in the absence of iron supplementation. Moreover, like humans, pigs are omnivorous and share many characteristics of human gut physiology, microbiota and immunity. In addition, their precocial nature permits early maternal separation, individual housing, and tight control of nutritional intake. Here, we highlight the advantages of piglets as valuable and highly relevant models for human infants in promoting understanding of how early iron status impacts physiological development. We also indicate how piglets offer potential to unravel the complexities of microbiota-immune responses during iron deficiency and in response to iron supplementation, and the link between these and increased risk of infectious disease.

Effects of Foods Fortified with Zinc, Alone or Cofortified with Multiple Micronutrients, on Health and Functional Outcomes: A Systematic Review and Meta-Analysis

Seventeen per cent of the world's population is estimated to be at risk of inadequate zinc intake, which could in part be addressed by zinc fortification of widely consumed foods. We conducted a review of efficacy and effectiveness studies to ascertain the effect of zinc fortification [postharvest fortification of an industrially produced food or beverage; alone or with multiple micronutrients (MMN)] on a range of health outcomes. Previous reviews have required that the effect of zinc be isolated; because zinc is always cofortified with MMN in existing fortification programs, we did not impose this condition. Outcomes assessed were zinc-related biomarkers (plasma or serum, hair or urine zinc concentrations, comet assay, plasma fatty acid concentrations, and the proportion of and total zinc absorbed in the intestine from the diet), child anthropometry, morbidity, mortality, cognition, plasma or serum iron and copper concentrations, and for observational studies, a change in consumption of the food vehicle. Fifty-nine studies were included in the review; 54 in meta-analyses, totaling 73 comparisons. Zinc fortification with and without MMN increased plasma zinc concentrations (efficacy, n = 27: 4.68 μg/dL; 95% CI: 2.62-6.75; effectiveness, n = 13: 6.28 μg/dL; 95% CI: 5.03-7.77 μg/dL) and reduced the prevalence of zinc deficiency (efficacy, n = 11: OR: 0.76, 95% CI: 0.60-0.96; effectiveness, n = 10: OR: 0.45, 95% CI: 0.31-0.64). There were statistically significant increases in child weight (efficacy, n = 11: 0.43 kg, 95% CI: 0.11-0.75 kg), improvements in short-term auditory memory (efficacy, n = 3: 0.32 point, 95% CI: 0.13-0.50 point), and decreased incidence of diarrhea (efficacy, n = 3: RR: 0.79, 95% CI: 0.68-0.92) and fever (efficacy, n = 2: RR: 0.85, 95% CI: 0.74-0.97). However, these effects cannot be solely attributed to zinc. Our review found that zinc fortification with or without MMN reduced the prevalence of zinc deficiency and may provide health and functional benefits, including a reduced incidence of diarrhea.

Effects of preventive nutrition interventions among adolescents on health and nutritional status in low- and middle-income countries: A systematic review

Background

Malnutrition is one of the most common causes of morbidity and mortality among children and adolescents and is now considered to be one of the largest risk factors responsible for the global burden of diseases along with poor diet.

Objectives

The objective of this review was to assess the impact of preventive nutrition interventions (including nutrition education and counselling; micronutrient supplementation/fortification and macronutrient supplementation) to improve the health and nutritional status of adolescents aged 10-19 years in low- and middle-income countries (LMICs). The secondary objective of the review was to assess various contextual factors based on the World Health Organisation (WHO) health system building blocks framework that might potentially impact the effectiveness of these interventions for this age group.

Search Methods

The search was conducted on Cochrane Controlled Trials Register (CENTRAL), MEDLINE, EMBASE, CINAHL, PsycINFO, the WHO nutrition databases, CAB Global Health, Social Science Citation Index, Scopus, WHO Global Health Index, ADOLEC and EPPI until February 5, 2019. We searched Google Scholar along with key nutrition agencies database such as Nutrition International, the Global Alliance for Improved Nutrition, the World Food Programme and HarvestPlus to search for nonindexed, grey literature to locate relevant programme evaluations and any additional trials. All searches were performed without any restrictions on publication date, language or publication status.

Selection Criteria

We included randomised controlled trials, quasiexperimental studies, controlled before-after studies and interrupted time series evaluating the effectiveness of preventive nutrition interventions among adolescents between 10 and 19 years of age from LMICs.

Data Collection and Analysis

Two review authors independently assessed trials for inclusion, assessed risk of bias and extracted data from included studies. Meta-analysis was conducted separately for each outcome and intervention. For dichotomous data, we reported risk ratios (RR) with 95% confidence intervals (CI). For continuous data, we reported the mean difference (MD) or standard mean difference (SMD) with 95% CI.

Main Results

This review summarises findings from a total of 10 studies from 15 papers including 10,802 participants. All the studies included in this review assessed the impact of micronutrient supplementation/fortification on health and nutritional status among adolescents in LMIC. We did not find any study assessing the impact of nutrition education and counselling or on macronutrient supplementation among adolescents. Micronutrient supplementation/fortification interventions included calcium/vitamin D supplementation/fortification, iron supplementation with or without folic acid, zinc supplementation and multiple micronutrient (MMN) fortification. The majority of the studies (eight out of 10 studies) included adolescent girls aged between 10 and 19 years of age. We did not find any large scale preventive nutrition intervention programmes targeting adolescents in LMICs. We are uncertain of the effect of iron supplementation with or without folic acid on anaemia (daily supplementation; RR: 1.04, 95% CI 0.88, 1.24; one study; 1,160 participants; low quality evidence. Weekly supplementation; RR: 1.07, 95% CI: 0.91, 1.26; one study; 1,247 participants; low quality evidence). We are uncertain of the effect of various micronutrient supplementation/fortification on body mass index (calcium/vitamin D supplementation; (MD: -0.01 kg/m2; 95% CI: -1.20, 1.17; two studies; 730 participants; I 2 94%; very low quality evidence, iron supplementation with or without folic acid; MD: 0.29 kg/m2; 95% CI: -0.25, 0.83; two studies; 652 participants; I 2 69%; very low quality evidence, zinc supplementation; MD: 0.35 kg/m2; 95% CI: -0.15, 0.85; one study; 382 participants; very low quality evidence) and MMN fortification; MD: 0.23 kg/m2, 95% CI: -0.11, 0.57; two studies; 943 participants; I 2 22%; very low quality evidence). None of the included studies reported any other primary outcomes including morbidity or adverse effects. Iron supplementation with or without folic acid may improve haemoglobin concentrations (MD: 0.42 g/dL, 95% CI: 0.13, 0.71; four studies; 1,020 participants; I 2 89%; low quality evidence). Calcium/vitamin D supplementation may improve serum 25(OH) D levels (standardised mean difference [SMD]: 2.85, 95% CI: 0.89, 4.82; two studies; 395 participants; I 2 99%; low quality evidence). We are uncertain of the effect of calcium only supplementation (MD: 0.02 g/cm2, 95% CI: -0.00, 0.04; one study; 233 participants; low quality outcome) and calcium + vitamin D supplementation (MD: 0.02 g/cm2, 95% CI: -0.00, 0.04; one study; 235 participants; low quality evidence) on total bone mineral density (BMD). We are uncertain of the effect of MMN fortification on haemoglobin concentrations (MD: -0.10 g/dL, 95% CI: -0.88, 0.68; two studies; 1102 participants; I 2 100%; very low quality evidence); calcium supplementation on total body bone mineral content (BMC); (MD: 30.20 g, 95% CI: -40.56, 100.96; one study; 233 participants; low quality evidence), calcium + vitamin D supplementation on total body BMC (MD: 21.60 g, 95% CI: -45.32, 88.52; one study; 235 participants; low quality evidence) and zinc supplementation on serum zinc levels (SMD: 6.94, 95% CI: -4.84, 18.71; two studies; 494 participants; very low quality evidence). One study reported the impact of iron supplementation with or without folic acid on cognition of adolescent girls suggesting improved cognition in most of the tests with daily or twice weekly supplementation compared to once weekly or no supplementation. None of the other secondary outcomes were reported including any other development outcomes and all-cause mortality. These findings warrant caution while interpreting due to very few studies and high heterogeneity.

Authors' Conclusions

There is limited evidence of micronutrient supplementation/fortification among adolescents on health and nutritional status in LMICs, with lack of evidence on nutrition education and counselling and macronutrient supplementation. The findings are generaliseable for adolescent girls since all studies (except one) targeted female adolescents.

Effects of Preventive Nutrition Interventions among Adolescents on Health and Nutritional Status in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis

The objective of this review was to assess the impact of preventive nutrition interventions on health and nutritional status of adolescents aged 10–19 years in low- and middle-income countries (LMICs). We searched the databases until 5 February 2019 without any restrictions on publication, date, language, or publication status. A total of 10 studies (15 papers) including 10,802 participants assessing the impact of micronutrient supplementation/fortification were included in this review. We did not find any study assessing the impact of nutrition education and counseling or macronutrient supplementation among adolescents. Among primary outcomes, we are uncertain of the effect of iron supplementation with or without folic acid on anemia (daily supplementation; relative risk (RR): 1.04, 95% confidence interval (CI) 0.42, 2.57; one study; 1160 participants; low-quality evidence; weekly supplementation; RR: 1.07, 95% CI: 0.46, 2.52; one study; 1247 participants; low-quality evidence). We are also uncertain of the effect of various micronutrient supplementation/fortification on body mass index (BMI) (calcium/vitamin D supplementation; (MD: −0.01 kg/m²; 95% CI: −1.20, 1.17; two studies; 730 participants; I² 94%; very-low-quality evidence, iron supplementation with or without folic acid; MD: 0.47 kg/m²; 95% CI: −0.17, 1.11; two studies; 652 participants; I² 37%; very-low-quality evidence, zinc supplementation; MD: 0.35 kg/m²; 95% CI: −0.15, 0.85; one study; 382 participants; very-low-quality evidence) and multiple micronutrient (MMN) fortification; MD: 0.23 kg/m², 95% CI: −0.11, 0.57; two studies; 943 participants; I² 22%; very-low-quality evidence). None of the included studies reported any other primary outcomes including morbidity or adverse effects. Among secondary outcomes, iron supplementation with or without folic acid may improve hemoglobin concentrations, and calcium/vitamin D supplementation may improve serum 25(OH)D levels, while calcium only supplementation and calcium and vitamin D supplementation may marginally improve total body bone mineral density (BMD). We are uncertain of the effect of MMN fortification on hemoglobin concentrations, calcium supplementation on total body bone mineral content (BMC), calcium + vitamin D supplementation on total body BMC, and zinc supplementation on zinc levels. There is limited evidence of micronutrient supplementation/fortification among adolescents, especially adolescent boys, on health and nutritional status in LMICs. These findings should be interpreted with caution due to the low quality and limited number of studies.

Iodine fortification of foods and condiments, other than salt, for preventing iodine deficiency disorders

BACKGROUND

Iodine deficiency disorders (IDD) affect close to 1.9 billion people worldwide, and are a major public health concern in many countries. Among children, iodine deficiency is the main cause of potentially preventable deficits of central nervous system development and impairment of cognitive function, as well as goitre and hypothyroidism in people of all ages. Salt iodisation is the preferred strategy for IDD prevention and control, however, in some instances where salt is not the major condiment, alternate vehicles for iodine fortification have been considered.

OBJECTIVES

To assess the effects of fortifying foods, beverages, condiments, or seasonings other than salt with iodine alone or in conjunction with other micronutrients, on iodine status and health-related outcomes in all populations.

SEARCH METHODS

Studies were identified through systematic searches of the following databases from their start date to January 2018: Cochrane Public Health Group Specialised Register; CENTRAL; MEDLINE; MEDLINE in Process; Embase; Web of Science; CINAHL; POPLINE; AGRICOLA; BIOSIS; Food Science and Technology Abstracts; OpenGrey; Bibliomap and TRoPHI; AGRIS; IBECS; Scielo; Global Index Medicus-AFRO and EMRO; LILACS; PAHO; WHOLIS; WPRO; IMSEAR; IndMED; and Native Health Research Database. We also searched reference list of relevant articles, conference proceedings, and databases of ongoing trials, and contacted experts and relevant organisations to identify any unpublished work. We applied no language or date restrictions.

SELECTION CRITERIA

Studies were eligible if they were randomised or quasi-randomised controlled trials (RCT) with randomisation at either the individual or cluster level (including cross-over trials), non-randomised RCTs, or prospective observational studies with a control group, such as cohort studies, controlled before-and-after studies, and interrupted time series. We included studies that examined the effects of fortification of food, beverage, condiment, or seasoning with iodine alone, or in combination with other micronutrients versus the same unfortified food, or no intervention. We considered the following measures: death (all-cause), goitre, physical development, mental development, cognitive function and motor skill development, cretinism, hypothyroidism, adverse effects (any reported by trialists), urinary iodine concentration, thyroid-stimulating hormone (TSH) concentration, and serum thyroglobulin concentration. We included all populations, including pregnant women, from any country.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data, and assessed risk of bias of included studies.We used random-effects meta-analyses to combine data and generate an overall estimate of treatment effect, when more than one study examined the same outcome measure. The overall effect estimate was calculated as the mean difference (MD) or standardised mean difference (SMD) between the intervention group and the comparison group for continuous outcomes, and as odds ratio (OR) for dichotomous outcomes. We assessed the level of heterogeneity through the I² statistic. We conducted post-hoc subgroup analyses to explore possible sources of heterogeneity, and sensitivity analyses to check the robustness of the findings from the primary analyses. We assessed the quality of the evidence for each outcome using the GRADE framework.Where it was not possible to pool the results in a meta-analysis, we provided a narrative summary of the outcomes.

MAIN RESULTS

Eleven studies met the criteria, providing 14 comparisons, and capturing data on 4317 participants. Seven studies were RCTs, three were cluster non-RCTs, and one was a randomised cross-over design. Seven studies were carried out among school children (N = 3636), three among women of reproductive age (N = 648), and one among infants (N = 33). The studies used diverse types of food as vehicle for iodine delivery: biscuits, milk, fish sauce, drinking water, yoghourt, fruit beverage, seasoning powder, and infant formula milk. Daily amounts of iodine provided ranged from 35 µg/day to 220 µg/day; trial duration ranged from 11 days to 48 weeks. Five studies examined the effect of iodine fortification alone, two against the same unfortified food, and three against no intervention. Six studies evaluated the effect of cofortification of iodine with other micronutrients versus the same food without iodine but with different levels of other micronutrients. We assessed one study to be at low risk of bias for all bias domains, three at low risk of bias for all domains apart from selective reporting, and seven at an overall rating of high risk of bias.No study assessed the primary outcomes of death, mental development, cognitive function, cretinism, or hypothyroidism, or secondary outcomes of TSH or serum thyroglobulin concentration. Two studies reported the effects on goitre, one on physical development measures, and one on adverse effects. All studies assessed urinary iodine concentration.The effects of iodine fortification compared to control on goitre prevalence (OR 1.60, 95% CI 0.60 to 4.31; 1 non-RCT, 83 participants; very low-quality evidence), and five physical development measures were uncertain (1 non-RCT, 83 participants; very low-quality evidence): weight (MD 0.23 kg, 95% CI -6.30 to 6.77); height (MD -0.66 cm, 95% CI -4.64 to 3.33); weight-for-age (MD 0.05, 95% CI -0.59 to 0.69); height-for-age (MD -0.30, 95% CI -0.75 to 0.15); and weight-for-height (MD -0.21, 95% CI -0.51 to 0.10). One study reported that there were no adverse events observed during the cross-over trial (low-quality evidence).Pooled results from RCTs showed that urinary iodine concentration significantly increased following iodine fortification (SMD 0.59, 95% CI 0.37 to 0.81; 6 RCTs, 2032 participants; moderate-quality evidence). This is equivalent to an increase of 38.32 µg/L (95% CI 24.03 to 52.61 µg/L). This effect was not observed in the meta-analysis of non-RCTs (SMD 0.25, 95% CI -0.16 to 0.66; 3 non-RCTs, 262 participants; very low-quality evidence). Sensitivity analyses did not change the effect observed in the primary analyses.

AUTHORS' CONCLUSIONS

The evidence on the effect of iodine fortification of foods, beverages, condiments, or seasonings other than salt on reducing goitre, improving physical development measures, and any adverse effects is uncertain. However, our findings suggest that the intervention likely increases urinary iodine concentration. Additional, adequately powered, high-quality studies on the effects of iodine fortification of foods on these, and other important outcomes, as well as its efficacy and safety, are required.

Еffects of fortified milk on cognitive abilities in school-aged children: results from a randomized-controlled trial

BACKGROUND

Micronutrients such as vitamins and minerals and long-chain polyunsaturated omega-3 fatty acids (PUFAs) are essential for children's brain development and cognitive functions. The current study investigated whether milk fortified with micronutrients and PUFA can result in improved cognitive function in mainstream school children.

METHODS

One-hundred-and-nineteen children (age 8-14, 58 boys) were randomly allocated to a fortified milk group or a regular full milk control group. Participants consumed 0.6L/day of the milk for 5 months. We recorded relevant biochemical, anthropometric, and cognitive measures (working memory and processing speed) at the start of the study and at follow-up after 5 months.

RESULTS

The fortified milk significantly increased docosahexaenoic acid (DHA) (change from baseline of 28% [95% CI 17-39%] vs. -6% [95% CI - 13 to 0%] in the control group) and serum 25OH-vitamin D concentrations (41% [95% CI 30-52%] vs. 21% [95% CI 11-30%] in the control group). The fortified milk improved working memory on one of two tests (32% [95% CI 17-47%] vs. 13% [95% CI 6-19%] in the control group). The fortified milk also indirectly increased processing speed on one of two tests; this effect was small and completely mediated by increases in 25OH-vitamin D concentrations.

CONCLUSIONS

These results suggest that fortifying milk with micronutrients and PUFA could be an effective and practical way to aid children's cognitive development.

Point-of-use fortification of foods with micronutrient powders containing iron in children of preschool and school-age

BACKGROUND

Approximately 600 million children of preschool and school age are anaemic worldwide. It is estimated that at least half of the cases are due to iron deficiency. Point-of-use fortification of foods with micronutrient powders (MNP) has been proposed as a feasible intervention to prevent and treat anaemia. It refers to the addition of iron alone or in combination with other vitamins and minerals in powder form, to energy-containing foods (excluding beverages) at home or in any other place where meals are to be consumed. MNPs can be added to foods either during or after cooking or immediately before consumption without the explicit purpose of improving the flavour or colour.

OBJECTIVES

To assess the effects of point-of-use fortification of foods with iron-containing MNP alone, or in combination with other vitamins and minerals on nutrition, health and development among children at preschool (24 to 59 months) and school (five to 12 years) age, compared with no intervention, a placebo or iron-containing supplements.

SEARCH METHODS

In December 2016, we searched the following databases: CENTRAL, MEDLINE, Embase, BIOSIS, Science Citation Index, Social Science Citation Index, CINAHL, LILACS, IBECS, Popline and SciELO. We also searched two trials registers in April 2017, and contacted relevant organisations to identify ongoing and unpublished trials.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs trials with either individual or cluster randomisation. Participants were children aged between 24 months and 12 years at the time of intervention. For trials with children outside this age range, we included studies where we were able to disaggregate the data for children aged 24 months to 12 years, or when more than half of the participants were within the requisite age range. We included trials with apparently healthy children; however, we included studies carried out in settings where anaemia and iron deficiency are prevalent, and thus participants may have had these conditions at baseline.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the eligibility of trials against the inclusion criteria, extracted data from included trials, assessed the risk of bias of the included trials and graded the quality of the evidence.

MAIN RESULTS

We included 13 studies involving 5810 participants from Latin America, Africa and Asia. We excluded 38 studies and identified six ongoing/unpublished trials. All trials compared the provision of MNP for point-of-use fortification with no intervention or placebo. No trials compared the effects of MNP versus iron-containing supplements (as drops, tablets or syrup).The sample sizes in the included trials ranged from 90 to 2193 participants. Six trials included participants younger than 59 months of age only, four included only children aged 60 months or older, and three trials included children both younger and older than 59 months of age.MNPs contained from two to 18 vitamins and minerals. The iron doses varied from 2.5 mg to 30 mg of elemental iron. Four trials reported giving 10 mg of elemental iron as sodium iron ethylenediaminetetraacetic acid (NaFeEDTA), chelated ferrous sulphate or microencapsulated ferrous fumarate. Three trials gave 12.5 mg of elemental iron as microencapsulated ferrous fumarate. Three trials gave 2.5 mg or 2.86 mg of elemental iron as NaFeEDTA. One trial gave 30 mg and one trial provided 14 mg of elemental iron as microencapsulated ferrous fumarate, while one trial gave 28 mg of iron as ferrous glycine phosphate.In comparison with receiving no intervention or a placebo, children receiving iron-containing MNP for point-of-use fortification of foods had lower risk of anaemia prevalence ratio (PR) 0.66, 95% confidence interval (CI) 0.49 to 0.88, 10 trials, 2448 children; moderate-quality evidence) and iron deficiency (PR 0.35, 95% CI 0.27 to 0.47, 5 trials, 1364 children; moderate-quality evidence) and had higher haemoglobin (mean difference (MD) 3.37 g/L, 95% CI 0.94 to 5.80, 11 trials, 2746 children; low-quality evidence).Only one trial with 115 children reported on all-cause mortality (zero cases; low-quality evidence). There was no effect on diarrhoea (risk ratio (RR) 0.97, 95% CI 0.53 to 1.78, 2 trials, 366 children; low-quality evidence).

AUTHORS' CONCLUSIONS

Point-of-use fortification of foods with MNPs containing iron reduces anaemia and iron deficiency in preschool- and school-age children. However, information on mortality, morbidity, developmental outcomes and adverse effects is still scarce.

A Randomized, Double-Blind Study Assessing Changes in Cognitive Function in Indian School Children Receiving a Combination of Bacopa monnieri and Micronutrient Supplementation vs. Placebo

Several studies have indicated a chronic cognitive enhancing effect of Bacopa monnieri across different ages and cognitive impairment associated with vitamin and mineral deficiencies in children. Therefore, we investigated the effects of 4-month supplementation with a combination of B. monnieri extract and multiple micronutrients on cognitive functions in Indian school children aged 7–12 years. This was a randomized, double-blind, parallel design, single-center study in which 300 children were randomized to receive a beverage either fortified with B. monnieri and multiple micronutrients (“fortified”) or a non-fortified isocaloric equivalent (“control”) twice-daily for 4 months. Cognitive function was assessed by the Cambridge Neuropsychological Automated Test Battery (CANTAB) administered at baseline, Day 60 and Day 121. The primary endpoint was change in short-term memory (working memory) from baseline in subjects receiving “fortified” vs. “control” beverages after 4 months. Secondary endpoints included sustained attention, episodic memory, and executive function. The “fortified” beverage did not significantly improve short-term memory or any of the secondary outcomes tested relative to the “control” beverage. However, the spatial working memory “strategy” score showed significant improvement on Day 60 (difference between groups in change from baseline: −0.55; p < 0.05), but not on Day 121 due to the active intervention. Study products were well-tolerated. Reasons for these unexpected findings are discussed.

Impact of Childhood Malnutrition on Host Defense and Infection

The global impact of childhood malnutrition is staggering. The synergism between malnutrition and infection contributes substantially to childhood morbidity and mortality. Anthropometric indicators of malnutrition are associated with the increased risk and severity of infections caused by many pathogens, including viruses, bacteria, protozoa, and helminths. Since childhood malnutrition commonly involves the inadequate intake of protein and calories, with superimposed micronutrient deficiencies, the causal factors involved in impaired host defense are usually not defined. This review focuses on literature related to impaired host defense and the risk of infection in primary childhood malnutrition. Particular attention is given to longitudinal and prospective cohort human studies and studies of experimental animal models that address causal, mechanistic relationships between malnutrition and host defense. Protein and micronutrient deficiencies impact the hematopoietic and lymphoid organs and compromise both innate and adaptive immune functions. Malnutrition-related changes in intestinal microbiota contribute to growth faltering and dysregulated inflammation and immune function. Although substantial progress has been made in understanding the malnutrition-infection synergism, critical gaps in our understanding remain. We highlight the need for mechanistic studies that can lead to targeted interventions to improve host defense and reduce the morbidity and mortality of infectious diseases in this vulnerable population.

The Impact of Nutritional Interventions beyond the First 2 Years of Life on Linear Growth: A Systematic Review and Meta-Analysis

A large body of evidence suggests that the first 1000 d from conception is a critical window in which interventions to address malnutrition will be most effective, but little is known about the impact on linear growth of nutritional interventions in children ≥2 y of age. The aim of this analysis was to evaluate the effectiveness of several nutrition-based interventions, specifically iron, zinc, calcium, iodine, vitamin A, multiple (≥2) micronutrients, protein, and food, at improving growth in children ≥2 y of age. A systematic search of MEDLINE and EMBASE retrieved 7794 articles. A total of 69 studies met prespecified inclusion criteria. Baseline height-for-age z score, age, nutrient dose, and study duration were examined as potential sources of heterogeneity. Zinc (mean effect size: 0.15; 95% CI: 0.06, 0.24), vitamin A (0.05; 95% CI: 0.01, 0.09), multiple micronutrients (0.26; 95% CI: 0.13, 0.39), and protein (0.68; 95% CI: 0.30, 1.05) had significant positive effects on linear growth, with baseline height-for-age z score as a significant inverse predictor of the effect size. Iron, calcium, iodine, and food-based interventions had no significant effect on growth. Age at baseline, study duration, and dose were not related to effect size for any nutrient examined. These findings suggest that zinc, vitamin A, multiple micronutrients, and protein interventions delivered after 24 mo of age can have a positive effect on linear growth, especially in populations that have experienced growth failure.

Oral zinc for treating diarrhoea in children

BACKGROUND

In developing countries, diarrhoea causes around 500,000 child deaths annually. Zinc supplementation during acute diarrhoea is currently recommended by the World Health Organization (WHO) and the United Nations Children's Fund (UNICEF).

OBJECTIVES

To evaluate oral zinc supplementation for treating children with acute or persistent diarrhoea.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (the Cochrane Library 2016, Issue 5), MEDLINE, Embase, LILACS, CINAHL, mRCT, and reference lists up to 30 September 2016. We also contacted researchers.

SELECTION CRITERIA

Randomized controlled trials (RCTs) that compared oral zinc supplementation with placebo in children aged one month to five years with acute or persistent diarrhoea, including dysentery.

DATA COLLECTION AND ANALYSIS

Both review authors assessed trial eligibility and risk of bias, extracted and analysed data, and drafted the review. The primary outcomes were diarrhoea duration and severity. We summarized dichotomous outcomes using risk ratios (RR) and continuous outcomes using mean differences (MD) with 95% confidence intervals (CI). Where appropriate, we combined data in meta-analyses (using either a fixed-effect or random-effects model) and assessed heterogeneity.We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

Thirty-three trials that included 10,841 children met our inclusion criteria. Most included trials were conducted in Asian countries that were at high risk of zinc deficiency. Acute diarrhoeaThere is currently not enough evidence from well-conducted RCTs to be able to say whether zinc supplementation during acute diarrhoea reduces death or number of children hospitalized (very low certainty evidence).In children older than six months of age, zinc supplementation may shorten the average duration of diarrhoea by around half a day (MD -11.46 hours, 95% CI -19.72 to -3.19; 2581 children, 9 trials, low certainty evidence), and probably reduces the number of children whose diarrhoea persists until day seven (RR 0.73, 95% CI 0.61 to 0.88; 3865 children, 6 trials, moderate certainty evidence). In children with signs of malnutrition the effect appears greater, reducing the duration of diarrhoea by around a day (MD -26.39 hours, 95% CI -36.54 to -16.23; 419 children, 5 trials, high certainty evidence).Conversely, in children younger than six months of age, the available evidence suggests zinc supplementation may have no effect on the mean duration of diarrhoea (MD 5.23 hours, 95% CI -4.00 to 14.45; 1334 children, 2 trials, moderate certainty evidence), or the number of children who still have diarrhoea on day seven (RR 1.24, 95% CI 0.99 to 1.54; 1074 children, 1 trial, moderate certainty evidence).None of the included trials reported serious adverse events. However, zinc supplementation increased the risk of vomiting in both age groups (children greater than six months of age: RR 1.57, 95% CI 1.32 to 1.86; 2605 children, 6 trials, moderate certainty evidence; children less than six months of age: RR 1.54, 95% CI 1.05 to 2.24; 1334 children, 2 trials, moderate certainty evidence). Persistent diarrhoeaIn children with persistent diarrhoea, zinc supplementation probably shortens the average duration of diarrhoea by around 16 hours (MD -15.84 hours, 95% CI -25.43 to -6.24; 529 children, 5 trials, moderate certainty evidence).

AUTHORS' CONCLUSIONS

In areas where the prevalence of zinc deficiency or the prevalence of malnutrition is high, zinc may be of benefit in children aged six months or more. The current evidence does not support the use of zinc supplementation in children less six months of age, in well-nourished children, and in settings where children are at low risk of zinc deficiency.

Fortification of staple foods with zinc for improving zinc status and other health outcomes in the general population

BACKGROUND

Zinc deficiency is a global nutritional problem, particularly in children and women residing in settings where diets are cereal based and monotonous. It has several negative health consequences. Fortification of staple foods with zinc may be an effective strategy for preventing zinc deficiency and improving zinc-related health outcomes.

OBJECTIVES

To evaluate the beneficial and adverse effects of fortification of staple foods with zinc on health-related outcomes and biomarkers of zinc status in the general population.

SEARCH METHODS

We searched the following databases in April 2015: Cochrane Central Register of Controlled Trials (CENTRAL, Issue 3 of 12, 2015, the Cochrane Library), MEDLINE & MEDLINE In Process (OVID) (1950 to 8 April 2015), EMBASE (OVID) (1974 to 8 April 2015), CINAHL (1982 to April 2015), Web of Science (1900 to 9 April 2015), BIOSIS (1969 to 9 April 2015), POPLINE (1970 to April 2015), AGRICOLA, OpenGrey, BiblioMap, and Trials Register of Promoting Health Interventions (TRoPHI), besides regional databases (April 2015) and theses. We also searched clinical trial registries (17 March 2015) and contacted relevant organisations (May 2014) in order to identify ongoing and unpublished studies.

SELECTION CRITERIA

We included randomised controlled trials, randomised either at the level of the individual or cluster. We also included non-randomised trials at the level of the individual if there was a concurrent comparison group. We included non-randomised cluster trials and controlled before-after studies only if there were at least two intervention sites and two control sites. Interventions included fortification (central/industrial) of staple foods (cereal flours, edible fats, sugar, condiments, seasonings, milk and beverages) with zinc for a minimum period of two weeks. Participants were members of the general population who were over two years of age (including pregnant and lactating women) from any country.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the eligibility of studies for inclusion, extracted data from included studies, and assessed the risk of bias of the included studies.

MAIN RESULTS

We included eight trials (709 participants); seven were from middle-income countries of Asia, Africa, Europe, and Latin America where zinc deficiency is likely to be a public health problem. Four trials compared the effect of zinc-fortified staple foods with unfortified foods (comparison 1), and four compared zinc-fortified staple foods in combination with other nutrients/factors with the same foods containing other nutrients or factors without zinc (comparison 2). The interventions lasted between one and nine months. We categorised most trials as having unclear or high risk of bias for randomisation, but low risk of bias for blinding and attrition. None of the studies in comparison 1 reported data on zinc deficiency.Foods fortified with zinc increased the serum or plasma zinc levels in comparison to foods without added zinc (mean difference (MD) 2.12 µmol/L, 95% confidence interval (CI) 1.25 to 3.00 µmol/L; 3 studies; 158 participants; low-quality evidence). Participants consuming foods fortified with zinc versus participants consuming the same food without zinc had similar risk of underweight (average risk ratio 3.10, 95% CI 0.52 to 18.38; 2 studies; 397 participants; low-quality evidence) and stunting (risk ratio (RR) 0.88, 95% CI 0.36 to 2.13; 2 studies; 397 participants; low-quality evidence). A single trial of addition of zinc to iron in wheat flour did not find a reduction in proportion of zinc deficiency (RR 0.17, 95% CI 0.01 to 3.94; very low-quality evidence). We did not find a difference in serum or plasma zinc levels in participants consuming foods fortified with zinc plus other micronutrients when compared with participants consuming the same foods with micronutrients but no added zinc (MD 0.03 µmol/L, 95% CI -0.67 to 0.72 µmol/L; 4 studies; 250 participants; low-quality evidence). No trial in comparison 2 provided information about underweight or stunting.There was no reported adverse effect of fortification of foods with zinc on indicators of iron or copper status.

AUTHORS' CONCLUSIONS

Fortification of foods with zinc may improve the serum zinc status of populations if zinc is the only micronutrient used for fortification. If zinc is added to food in combination with other micronutrients, it may make little or no difference to the serum zinc status. Effects of fortification of foods with zinc on other outcomes including zinc deficiency, children's growth, cognition, work capacity of adults, or on haematological indicators are unknown. Given the small number of trials and participants in each trial, further investigation of these outcomes is required.

Micronutrient Fortified Condiments and Noodles to Reduce Anemia in Children and Adults--A Literature Review and Meta-Analysis

Micronutrient deficiencies impose a considerable burden of disease on many middle and low income countries. Several strategies have been shown to be effective in improving micronutrient deficiencies. However, the impact of fortified condiments as well as fortified noodles is less well documented. We aimed to investigate existing evidence on the impact of micronutrient fortified condiments and noodles on hemoglobin, anemia, and functional outcomes in children and adults (age: 5 to 50 years). We conducted a literature review in electronic databases. In addition, we screened the homepages of relevant organizations and journals. We included randomized controlled trials (RCT). Of 1046 retrieved studies, 14 RCT provided data for the meta-analysis. Micronutrient fortification of condiments and noodles increased hemoglobin concentrations by 0.74 g/dL (95%-confidence intervals (95%-CI): 0.56 to 0.93; 12 studies) and 0.3 g/dL (95%-CI: 0.12 to 0.48; 1 study), respectively. Micronutrient fortification also led to a reduced risk of having anemia (risk ratio 0.59 (95%-CI 0.44 to 0.80)). Ferritin concentrations increased with fortified condiments. Functional outcomes were rarely assessed and showed mixed results. The use of micronutrient fortified condiments can be a strategy to reduce anemia in children and adults due to micronutrient deficiencies. The effect of fortified noodles seems to be smaller.

Bioavailability of iron, vitamin A, zinc, and folic acid when added to condiments and seasonings

Seasonings and condiments can be candidate vehicles for micronutrient fortification if consumed consistently and if dietary practices ensure bioavailability of the nutrient. In this review, we identify factors that may affect the bioavailability of iron, vitamin A, zinc, and folic acid when added to seasonings and condiments and evaluate their effects on micronutrient status. We take into consideration the chemical and physical properties of different forms of the micronutrients, the influence of the physical and chemical properties of foods and meals to which fortified seasonings and condiments are typically added, and interactions between micronutrients and the physiological and nutritional status of the target population. Bioavailable fortificants of iron have been developed for use in dry or fluid vehicles. For example, sodium iron ethylenediaminetetraacetic acid (NaFeEDTA) and ferrous sulfate with citric acid are options for iron fortification of fish and soy sauce. Furthermore, NaFeEDTA, microencapsulated ferrous fumarate, and micronized elemental iron are potential fortificants in curry powder and salt. Dry forms of retinyl acetate or palmitate are bioavailable fortificants of vitamin A in dry candidate vehicles, but there are no published studies of these fortificants in fluid vehicles. Studies of zinc and folic acid bioavailability in seasonings and condiments are also lacking.

Iron fortification adversely affects the gut microbiome, increases pathogen abundance and induces intestinal inflammation in Kenyan infants

BACKGROUND

In-home iron fortification for infants in developing countries is recommended for control of anaemia, but low absorption typically results in >80% of the iron passing into the colon. Iron is essential for growth and virulence of many pathogenic enterobacteria. We determined the effect of high and low dose in-home iron fortification on the infant gut microbiome and intestinal inflammation.

METHODS

We performed two double-blind randomised controlled trials in 6-month-old Kenyan infants (n=115) consuming home-fortified maize porridge daily for 4 months. In the first, infants received a micronutrient powder (MNP) containing 2.5 mg iron as NaFeEDTA or the MNP without iron. In the second, they received a different MNP containing 12.5 mg iron as ferrous fumarate or the MNP without the iron. The primary outcome was gut microbiome composition analysed by 16S pyrosequencing and targeted real-time PCR (qPCR). Secondary outcomes included faecal calprotectin (marker of intestinal inflammation) and incidence of diarrhoea. We analysed the trials separately and combined.

RESULTS

At baseline, 63% of the total microbial 16S rRNA could be assigned to Bifidobacteriaceae but there were high prevalences of pathogens, including Salmonella Clostridium difficile, Clostridium perfringens, and pathogenic Escherichia coli. Using pyrosequencing, +FeMNPs increased enterobacteria, particularly Escherichia/Shigella (p=0.048), the enterobacteria/bifidobacteria ratio (p=0.020), and Clostridium (p=0.030). Most of these effects were confirmed using qPCR; for example, +FeMNPs increased pathogenic E. coli strains (p=0.029). +FeMNPs also increased faecal calprotectin (p=0.002). During the trial, 27.3% of infants in +12.5 mgFeMNP required treatment for diarrhoea versus 8.3% in -12.5 mgFeMNP (p=0.092). There were no study-related serious adverse events in either group.

CONCLUSIONS

In this setting, provision of iron-containing MNPs to weaning infants adversely affects the gut microbiome, increasing pathogen abundance and causing intestinal inflammation.

TRIAL REGISTRATION NUMBER

NCT01111864.

Vitamin D status among Thai school children and the association with 1,25-Dihydroxyvitamin D and parathyroid hormone levels

In several low latitude countries, vitamin D deficiency is emerging as a public health issue. Adequate vitamin D is essential for bone health in rapidly growing children. In the Thai population, little is known about serum 25-hydroxyvitamin D [25(OH)D] status of infants and children. Moreover, the association between 25(OH)D and the biological active form of 1,25-dihydroxyvitamin D [1,25(OH)]₂D is not clear. The specific aims of this study were to characterize circulating serum 25(OH)D, 1,25(OH)₂D and their determinants including parathyroid hormone (PTH), age, sex, height and body mass index (BMI) in 529 school-aged Thai children aged 6–14 y. Adjusted linear regression analysis was performed to examine the impact of age and BMI, and its interaction with sex, on serum 25(OH)D concentrations and 1,25(OH)₂D concentrations. Serum 25(OH)D, 1,25(OH)₂D and PTH concentrations (geometric mean ± geometric SD) were 72.7±1.2 nmol/L, 199.1±1.3 pmol/L and 35.0±1.5 ng/L, respectively. Only 4% (21 of 529) participants had a serum 25(OH)D level below 50 nmol/L. There was statistically significant evidence for an interaction between sex and age with regard to 25(OH)D concentrations. Specifically, 25(OH)D concentrations were 19% higher in males. Moreover, females experienced a statistically significant 4% decline in serum 25(OH)D levels for each increasing year of age (P = 0.001); no decline was seen in male participants with increasing age (P = 0.93). When BMI, age, sex, height and serum 25(OH)D were individually regressed on 1,25(OH)₂D, height and sex were associated with 1,25(OH)₂D with females exhibiting statistically significantly higher serum 1,25(OH)₂D levels compared with males (P<0.001). Serum 1,25(OH)₂D among our sample of children exhibiting fairly sufficient vitamin D status were higher than previous reports suggesting an adaptive mechanism to maximize calcium absorption.

Single-micronutrient and broad-spectrum micronutrient approaches for treating mood disorders in youth and adults

Several different vitamins and minerals appear to be effective augmenting agents for mood-modifying drugs, but are not potent monotherapies in themselves for treating psychiatric disorders. In contrast, broad-spectrum micronutrient interventions appear in early trials to be as effective as psychiatric medications with fewer adverse effects for treating mood disorders, ADHD, aggressivity, and misconduct in youth and adults. Broad-spectrum treatments also may improve stress responses, cognition, and sense of well-being in healthy adults, but have been less well studied in youth. Current clinical data justify an extensive expansion of research on micronutrient mechanisms and treatments in psychiatry.

The effect of iodine-deficiency disorders on academic achievement of schoolchildren in Southern Ethiopia

OBJECTIVE

The present study aimed to assess the effect of iodine deficiency on academic achievement of schoolchildren in Wolaita Sodo town, Southern Ethiopia.

DESIGN

School-based comparative cross-sectional study.

SETTINGS

Primary school in Sodo town, Southern Ethiopia.

SUBJECTS

A sample population of 270 children with goitre and 264 without goitre. All students in each class were examined for the presence of goitre and classified based on WHO recommendations.

RESULTS

Among children with goitre, a higher proportion (54·8 %) was female and the proportion increased with age. The odds of scoring low on school performance was higher among children whose fathers were illiterate (adjusted OR = 1·9; 95 % CI 1·1, 3·5) and those who were absent for more than 5 d in the last academic year (adjusted OR = 1·5; 95 % CI 1·1, 2·3). Goitre was significantly associated with low academic achievement (adjusted OR = 1·8; 95 % CI 1·2, 2·5).

CONCLUSIONS

The study showed that the presence of goitre has a negative effect on academic achievement even after accounting for parental education and absenteeism from school. Awareness of endemic goitre and its impact on school performance, and an emphasis on prevention and control by concerned bodies, are recommended to alleviate the problem.

Vitamin A deficiency is associated with gastrointestinal and respiratory morbidity in school-age children

Infection is an important cause of morbidity throughout childhood. Poor micronutrient status is a risk factor for infection-related morbidity in young children, but it is not clear whether these associations persist during school-age years. We examined the relation between blood concentrations of micronutrient status biomarkers and risk of gastrointestinal and respiratory morbidity in a prospective study of 2774 children aged 5-12 y from public schools in Bogotá, Colombia. Retinol, zinc, ferritin, mean corpuscular volume, hemoglobin, erythrocyte folate, and vitamin B-12 concentrations were measured in blood at enrollment into the cohort. Children were followed for 1 academic year for incidence of morbidity, including diarrhea with vomiting, cough with fever, earache or ear discharge with fever, and doctor visits. Compared with adequate vitamin A status (≥30.0 μg/dL), vitamin A deficiency (<10.0 μg/dL) was associated with increased risk of diarrhea with vomiting [unadjusted incidence rate ratio (IRR): 2.17; 95% CI: 0.95, 4.96; P-trend = 0.03] and cough with fever (unadjusted IRR: 2.36; 95% CI: 1.30, 4.31; P-trend = 0.05). After adjustment for several sociodemographic characteristics and hemoglobin concentrations, every 10 μg/dL plasma retinol was associated with 18% fewer days of diarrhea with vomiting (P < 0.001), 10% fewer days of cough with fever (P < 0.001), and 6% fewer doctor visits (P = 0.01). Every 1 g/dL of hemoglobin was related to 17% fewer days with ear infection symptoms (P < 0.001) and 5% fewer doctor visits (P = 0.009) after controlling for sociodemographic factors and retinol concentrations. Zinc, ferritin, mean corpuscular volume, erythrocyte folate, and vitamin B-12 status were not associated with morbidity or doctor visits. Vitamin A and hemoglobin concentrations were inversely related to rates of morbidity in school-age children. Whether vitamin A supplementation reduces the risk or severity of infection in children over 5 y of age needs to be determined.

Oral zinc supplementation may improve cognitive function in schoolchildren

Zinc is an important micronutrient for humans, and zinc deficiency among schoolchildren is deleterious to growth and development, immune competence, and cognitive function. However, the effect of zinc supplementation on cognitive function remains poorly understood. The purpose of our study was to evaluate the effect of oral zinc supplementation (5 mg Zn/day for 3 months) on the Full Scale Intelligence Quotient (FSIQ), Verbal Intelligence Quotient (VIQ), and Performance Intelligence Quotient (PIQ) using a Wechsler Intelligence Scale for Children (WISC-III). We studied 36 schoolchildren aged 6 to 9 years (7.8 ± 1.1) using a nonprobability sampling method. The baseline serum zinc concentrations increased significantly after zinc supplementation (p < 0.0001), with no difference between sexes. Tests were administered under basal conditions before and after zinc supplementation, and there was no difference in FSIQ according to gender or age. The results demonstrated that zinc improved the VIQ only in the Information Subtest (p = 0.009), although the supplementation effects were more significant in relation to the PIQ, as these scores improved for the Picture Completion, Picture Arrangement, Block Design, and Object Assembly Subtests (p = 0.0001, for all subtests). In conclusion, zinc supplementation improved specific cognitive abilities, thereby positively influencing the academic performance of schoolchildren, even those without marginal zinc deficiency.

Micronutrient fortification of food and its impact on woman and child health: a systematic review

BACKGROUND

Vitamins and minerals are essential for growth and metabolism. The World Health Organization estimates that more than 2 billion people are deficient in key vitamins and minerals. Groups most vulnerable to these micronutrient deficiencies are pregnant and lactating women and young children, given their increased demands. Food fortification is one of the strategies that has been used safely and effectively to prevent vitamin and mineral deficiencies.

METHODS

A comprehensive search was done to identify all available evidence for the impact of fortification interventions. Studies were included if food was fortified with a single, dual or multiple micronutrients and impact of fortification was analyzed on the health outcomes and relevant biochemical indicators of women and children. We performed a meta-analysis of outcomes using Review Manager Software version 5.1.

RESULTS

Our systematic review identified 201 studies that we reviewed for outcomes of relevance. Fortification for children showed significant impacts on increasing serum micronutrient concentrations. Hematologic markers also improved, including hemoglobin concentrations, which showed a significant rise when food was fortified with vitamin A, iron and multiple micronutrients. Fortification with zinc had no significant adverse impact on hemoglobin levels. Multiple micronutrient fortification showed non-significant impacts on height for age, weight for age and weight for height Z-scores, although they showed positive trends. The results for fortification in women showed that calcium and vitamin D fortification had significant impacts in the post-menopausal age group. Iron fortification led to a significant increase in serum ferritin and hemoglobin levels in women of reproductive age and pregnant women. Folate fortification significantly reduced the incidence of congenital abnormalities like neural tube defects without increasing the incidence of twinning. The number of studies pooled for zinc and multiple micronutrients for women were few, though the evidence suggested benefit. There was a dearth of evidence for the impact of fortification strategies on morbidity and mortality outcomes in women and children.

CONCLUSION

Fortification is potentially an effective strategy but evidence from the developing world is scarce. Programs need to assess the direct impact of fortification on morbidity and mortality.

Early-stage primary school children attending a school in the Malawian School Feeding Program (SFP) have better reversal learning and lean muscle mass growth than those attending a non-SFP school

In developing countries, schoolchildren encounter a number of challenges, including failure to complete school, poor health and nutrition, and poor academic performance. Implementation of school feeding programs (SFPs) in less developed countries is increasing and yet there is mixed evidence regarding their positive effects on nutrition, education, and cognition at the population level. This study evaluated cognitive and anthropometric outcomes in entry-level primary school children in Malawi with the aim of generating evidence for the ongoing debate about SFPs in Malawi and other developing countries. A total of 226 schoolchildren aged 6-8 y in 2 rural Malawian public primary schools were followed for one school year. Children attending one school (SFP school) received a daily ration of corn-soy blend porridge, while those attending the other (non-SFP school) did not. Baseline and post-baseline outcomes included the Cambridge Neurological Test Automated Battery cognitive tests of paired associate learning, rapid visual information processing and intra-extra dimensional shift, and anthropometric measurements of weight, height, and mid-upper arm circumference (MUAC). At follow-up, the SFP subcohort had a greater reduction than the non-SFP subcohort in the number of intra-extra predimensional shift errors made (mean 18.5 and 24.9, respectively; P-interaction = 0.02) and also showed an increase in MUAC (from 16.3 to 17.0; P-interaction <0.0001). The results indicate that the SFP in Malawi is associated with an improvement in reversal learning and catch-up growth in lean muscle mass in children in the SFP school compared with children in the non-SFP school. These findings suggest that the Malawian SFP, if well managed and ration sizes are sustained, may have the potential to improve nutritional and cognitive indicators of the most disadvantaged children.

Oral zinc for treating diarrhoea in children

BACKGROUND

In developing countries, diarrhoea causes around two million child deaths annually. Zinc supplementation during acute diarrhoea is currently recommended by the World Health Organization and UNICEF.

OBJECTIVES

To evaluate oral zinc supplementation for treating children with acute or persistent diarrhoea.

SEARCH METHODS

In February 2012, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library 2011, Issue 11), MEDLINE, EMBASE, LILACS, CINAHL, mRCT, and reference lists. We also contacted researchers.

SELECTION CRITERIA

Randomized controlled trials comparing oral zinc supplementation with placebo in children aged one month to five years with acute or persistent diarrhoea, including dysentery.

DATA COLLECTION AND ANALYSIS

Both authors assessed trial eligibility and risk of bias, extracted and analysed data, and drafted the review. Diarrhoea duration and severity were the primary outcomes. We summarized dichotomous outcomes using risk ratios (RR) and continuous outcomes using mean differences (MD) with 95% confidence intervals (CI). Where appropriate, we combined data in meta-analyses (using the fixed- or random-effects model) and assessed heterogeneity.The quality of evidence has been assessed using the GRADE methods

MAIN RESULTS

Twenty-four trials, enrolling 9128 children, met our inclusion criteria. The majority of the data is from Asia, from countries at high risk of zinc deficiency, and may not be applicable elsewhere. Acute diarrhoea. There is currently not enough evidence from well conducted randomized controlled trials to be able to say whether zinc supplementation during acute diarrhoea reduces death or hospitalization (very low quality evidence).In children aged greater than six months with acute diarrhoea, zinc supplementation may shorten the duration of diarrhoea by around 10 hours (MD -10.44 hours, 95% CI -21.13 to 0.25; 2175 children, six trials, low quality evidence), and probably reduces the number of children whose diarrhoea persists until day seven (RR 0.73, 95% CI 0.61 to 0.88; 3865 children, six trials, moderate quality evidence). In children with signs of moderate malnutrition the effect appears greater, reducing the duration of diarrhoea by around 27 hours (MD -26.98 hours, 95% CI -14.62 to -39.34; 336 children, three trials, high quality evidence).Conversely, In children aged less than six months, the available evidence suggests zinc supplementation may have no effect on mean diarrhoea duration (MD 5.23 hours, 95% CI -4.00 to 14.45; 1334 children, two trials, low quality evidence), and may even increase the proportion of children whose diarrhoea persists until day seven (RR 1.24, 95% CI 0.99 to 1.54; 1074 children, one trial, moderate quality evidence).No trials reported serious adverse events, but zinc supplementation during acute diarrhoea causes vomiting in both age groups (RR 1.59, 95% 1.27 to 1.99; 5189 children, 10 trials, high quality evidence). Persistent diarrhoea. In children with persistent diarrhoea, zinc supplementation probably shortens the duration of diarrhoea by around 16 hours (MD -15.84 hours, 95% CI -25.43 to -6.24; 529 children, five trials, moderate quality evidence).

AUTHORS' CONCLUSIONS

In areas where the prevalence of zinc deficiency or the prevalence of moderate malnutrition is high, zinc may be of benefit in children aged six months or more.The current evidence does not support the use of zinc supplementation in children below six months of age.

Vitamin D, cognition, and dementia: a systematic review and meta-analysis

OBJECTIVE

To examine the association between cognitive function and dementia with vitamin D concentration in adults.

METHODS

Five databases were searched for English-language studies up to August 2010, and included all study designs with a comparative group. Cognitive function or impairment was defined by tests of global or domain-specific cognitive performance and dementia was diagnosed according to recognized criteria. A vitamin D measurement was required. Two authors independently extracted data and assessed study quality using predefined criteria. The Q statistic and I² methods were used to test for heterogeneity. We conducted meta-analyses using random effects models for the weighted mean difference (WMD) and Hedge's g.

RESULTS

Thirty-seven studies were included; 8 contained data allowing mean Mini-Mental State Examination (MMSE) scores to be compared between participants with vitamin D <50 nmol/L to those with values ≥50 nmol/L. There was significant heterogeneity among the studies that compared the WMD for MMSE but an overall positive effect for the higher vitamin D group (1.2, 95% confidence interval [CI] 0.5 to 1.9; I² = 0.65; p = 0.002). The small positive effect persisted despite several sensitivity analyses. Six studies presented data comparing Alzheimer disease (AD) to controls but 2 utilized a method withdrawn from commercial use. For the remaining 4 studies the AD group had a lower vitamin D concentration compared to the control group (WMD = -6.2 nmol/L, 95% CI -10.6 to -1.8) with no heterogeneity (I² < 0.01; p = 0.53).

CONCLUSION

These results suggest that lower vitamin D concentrations are associated with poorer cognitive function and a higher risk of AD. Further studies are required to determine the significance and potential public health benefit of this association.

Oral zinc for treating diarrhoea in children

BACKGROUND

In developing countries, diarrhoea causes around two million child deaths annually. Zinc supplementation during acute diarrhoea is currently recommended by the World Health Organization and UNICEF.

OBJECTIVES

To evaluate oral zinc supplementation for treating children with acute or persistent diarrhoea.

SEARCH METHODS

In February 2012, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library 2011, Issue 11), MEDLINE, EMBASE, LILACS, CINAHL, mRCT, and reference lists. We also contacted researchers.

SELECTION CRITERIA

Randomized controlled trials comparing oral zinc supplementation with placebo in children aged one month to five years with acute or persistent diarrhoea, including dysentery.

DATA COLLECTION AND ANALYSIS

Both authors assessed trial eligibility and risk of bias, extracted and analysed data, and drafted the review. Diarrhoea duration and severity were the primary outcomes. We summarized dichotomous outcomes using risk ratios (RR) and continuous outcomes using mean differences (MD) with 95% confidence intervals (CI). Where appropriate, we combined data in meta-analyses (using the fixed- or random-effects model) and assessed heterogeneity.The quality of evidence has been assessed using the GRADE methods

MAIN RESULTS

Twenty-four trials, enrolling 9128 children, met our inclusion criteria. The majority of the data is from Asia, from countries at high risk of zinc deficiency, and may not be applicable elsewhere.Acute diarrhoeaThere is currently not enough evidence from well conducted randomized controlled trials to be able to say whether zinc supplementation during acute diarrhoea reduces death or hospitalization (very low quality evidence).In children aged greater than six months with acute diarrhoea, zinc supplementation may shorten the duration of diarrhoea by around 10 hours (MD -10.44 hours, 95% CI -21.13 to 0.25; 2091 children, five trials, low quality evidence), and probably reduces the number of children whose diarrhoea persists until day seven (RR 0.73, 95% CI 0.61 to 0.88; 3865 children, six trials, moderate quality evidence). In children with signs of moderate malnutrition the effect appears greater, reducing the duration of diarrhoea by around 27 hours (MD -26.98 hours, 95% CI -14.62 to -39.34; 336 children, three trials, high quality evidence).Conversely, In children aged less than six months, the available evidence suggests zinc supplementation may have no effect on mean diarrhoea duration (MD 5.23 hours, 95% CI -4.00 to 14.45; 1334 children, two trials, low quality evidence), and may even increase the proportion of children whose diarrhoea persists until day seven (RR 1.24, 95% CI 0.99 to 1.54; 1074 children, one trial, moderate quality evidence).No trials reported serious adverse events, but zinc supplementation during acute diarrhoea causes vomiting in both age groups (RR 1.59, 95% 1.27 to 1.99; 5189 children, 10 trials, high quality evidence).Persistent diarrhoeaIn children with persistent diarrhoea, zinc supplementation probably shortens the duration of diarrhoea by around 16 hours (MD -15.84 hours, 95% CI -25.43 to -6.24; 529 children, five trials, moderate quality evidence).

AUTHORS' CONCLUSIONS

In areas where the prevalence of zinc deficiency or the prevalence of moderate malnutrition is high, zinc may be of benefit in children aged six months or more.The current evidence does not support the use of zinc supplementation in children below six months of age.

The effect of a 1-year multiple micronutrient or n-3 fatty acid fortified food intervention on morbidity in Indian school children

BACKGROUND/OBJECTIVES

Few studies have shown that supplementation with micronutrients (MNs) or n-3 fatty acids may have health benefits such as reduced morbidity in schoolchildren. The effect of a combination of these nutrients has never been investigated. This study aimed to determine the effect of a combination of two different doses of MN and n-3 fatty acids on morbidity in schoolchildren in Bangalore, India.

SUBJECTS/METHODS

In all 598 children (6-10 years) received foods fortified with either high (100% recommended dietary allowance) or low (15% recommended dietary allowance) MN, combined with either high (900 mg α-linolenic acid (ALA) plus 100 mg docosahexaenoic acid) or low (140 mg ALA) n-3 fatty acids for 1 year. Morbidity was measured by weekly self-reports using a structured questionnaire. Poisson regression analyses of episodes/child/year and duration/episode adjusted for age and sex were performed on clusters of symptoms, including upper and lower respiratory tract infections (URTI and LRTI), gastrointestinal complaints (GI) and general symptoms of illness to observe MN and n-3 fatty acid treatment effects.

RESULTS

Children consuming high n-3 fatty acids had significantly fewer episodes of URTI/child/year (relative risk (RR)=0.88, 95% confidence interval (CI): 0.79, 0.97) and significantly shorter duration/episode of URTI (RR=0.81, 95% CI: 0.78, 0.85), LRTI (RR=0.91, 95% CI: 0.85, 0.97), GI complaints (RR=0.79, 95% CI: 0.74, 0.85) and general symptoms (RR=0.90, 95% CI: 0.82, 0.98) compared with children who received low n-3 fatty acid intervention. The high MN intervention reduced the duration of general symptoms (RR=0.89, 95% CI: 0.82, 0.98).

CONCLUSION

Although n-3 fatty acids may be beneficial for reducing illness in Indian schoolchildren, more research is needed to confirm presence of combined effect with MN.

Decreased parasite load and improved cognitive outcomes caused by deworming and consumption of multi-micronutrient fortified biscuits in rural Vietnamese schoolchildren

Micronutrient deficiencies are associated with impaired growth and cognitive function. A school-based fortification program might benefit schoolchildren but a high prevalence of parasite infestation might affect effectiveness. A randomized, double-blind, placebo-controlled 2 × 2 factorial trial was conducted to assess the efficacy of multi-micronutrient fortified biscuits with or without de-worming on growth, cognitive function, and parasite load in Vietnamese schoolchildren. Schoolchildren (n = 510), 6-8 years of age were randomly allocated to receive albendazole or placebo at baseline and four months of multi-micronutrient fortified biscuits (FB) or non-fortified biscuits. Children receiving FB for four months scored higher on two cognitive tests: Raven's Colored Progressive Matrices and the Digit Span Forward test. Children receiving albendazole plus FB had the lowest parasite load after four months. In children receiving FB, mid-upper arm circumference was slightly improved (+0.082 cm) but there were no differences in other indexes of anthropometry. Combining multi-micronutrient fortified biscuits with de-worming is an effective strategy.

A multi-micronutrient beverage enhances the vitamin A and zinc status of Nigerian primary schoolchildren

Schoolchildren in Nigeria are rarely targeted by micronutrient interventions. We completed a 6-mo, double-blind, placebo-controlled trial to determine the effects of a multi-micronutrient beverage on biochemical and anthropometric indicators of nutritional status among schoolchildren participating in a pilot school feeding program in Nasarawa State, Nigeria. Children received 1 of 2 interventions 5 d/wk during school hours: 1) 250 mL/d of a multi-micronutrient beverage that included vitamin A, iron, and zinc (micronutrient); or 2) an isoenergetic control beverage (control). At baseline, 566 children 5-13 y old were randomized to groups (micronutrient: n = 288; control: n = 278). Height, weight, hemoglobin, and serum concentrations of C-reactive protein, ferritin, retinol, and zinc were measured at baseline and at the end of the study. A total of 270 children in the micronutrient group and 264 children in the control group completed the study. Self-reports of vomiting increased in both groups at 6 mo; however, the prevalence tended to be greater in the micronutrient group (21%) compared to the control group (14%) (P = 0.06). Biochemical changes were greater in the micronutrient group compared to control for serum retinol (0.10 ± 0.02 μmol/L vs. 0.02 ± 0.02 μmol/L; P = 0.016) and zinc (1.0 ± 0.2 μmol/L vs. 0.6 ± 0.2 μmol/L; P = 0.031). The intervention did not significantly affect hemoglobin or serum ferritin concentrations. The cost effectiveness of the intervention needs to be further evaluated, as does the efficacy of the beverage on anemia and indicators of iron status.

Can multi-micronutrient food fortification improve the micronutrient status, growth, health, and cognition of schoolchildren? A systematic review

Micronutrient deficiencies compromise the health and development of many school-age children worldwide. Previous research suggests that micronutrient interventions might benefit the health and development of school-age children and that multiple micronutrients might be more effective than single micronutrients. Fortification of food is a practical way to provide extra micronutrients to children. Earlier reviews of (multiple) micronutrient interventions in school-age children did not distinguish between supplementation or fortification studies. The present review includes studies that tested the impact of multiple micronutrients provided via fortification on the micronutrient status, growth, health, and cognitive development of schoolchildren. Twelve eligible studies were identified. Eleven of them tested the effects of multiple micronutrients provided via fortified food compared to unfortified food. One study compared fortification with multiple micronutrients to fortification with iodine alone. Multi-micronutrient food fortification consistently improved micronutrient status and reduced anemia prevalence. Some studies reported positive effects on morbidity, growth, and cognitive outcomes, but the overall effects on these outcomes were equivocal.

Effect of vitamin A, vitamin A plus iron and multiple micronutrient-fortified seasoning powder on infectious morbidity of preschool children

OBJECTIVE

Improvement of hemoglobin and serum retinol and facilitation of the mobilization of iron storage were achieved with a multiple-micronutrient-fortified diet in preschoolers for 6 mo in a suburb of Chongqing, China. We investigated whether fortification with multiple micronutrients in a diet for preschool children results in changes in children's infectious morbidity compared with diets fortified solely with vitamin A and with vitamin A plus iron.

METHODS

From December 2005 to June 2006, 226 2- to 6-y-old preschool children were recruited from three nurseries randomly assigned to three different fortified-diet groups for 6 mo. Group I was fortified with vitamin A; groups II and III were fortified with vitamin A plus iron and vitamin A plus iron, thiamine, riboflavin, folic acid, niacinamide, zinc, and calcium, respectively. The secondary functional outcomes, morbidity of diarrhea and respiratory infection, were collected during supplementation.

RESULTS

The groups were comparable concerning compliance and loss to follow-up. There was evidence of a lower incidence rate of respiratory-related illnesses, diarrhea-related illness, fewer symptoms of runny nose, cough, and fever, and shorter duration of respiratory-related illnesses and cough for children in group III compared with children in groups I and II. However, there was no significantly or clinically important difference between children in groups I and II.

CONCLUSION

The beneficial effects on infectious morbidity over 6 mo, in addition to some biochemical improvements, highlight the potential of this micronutrient-fortified seasoning powder supplied in a diet for preschool children.

Iodine deficiency in pregnancy, infancy and childhood and its consequences for brain development

Iodine deficiency during foetal development and early childhood is associated with cognitive impairment. Randomised clinical studies in school-aged children encountered in the literature indicate that cognitive performance can be improved by iodine supplementation, but most studies suffer from methodological constraints. Tests to assess cognitive performance in the domains that are potentially affected by iodine deficiency need to be refined. Maternal iodine supplementation in areas of mild-to-moderate iodine deficiency may improve cognitive performance of the offspring, but randomised controlled studies with long-term outcomes are lacking. Studies in infants or young children have not been conducted. The best indicators for iodine deficiency in children are thyroid-stimulating hormone (TSH) in newborns and thyroglobulin (Tg) in older children. Urinary iodine may also be useful but only at the population level. Adequate salt iodisation will cover the requirements of infants and children as well as pregnant women. However, close monitoring remains essential.

Hand sanitisers for reducing illness absences in primary school children in New Zealand: a cluster randomised controlled trial study protocol

Background

New Zealand has relatively high rates of morbidity and mortality from infectious disease compared with other OECD countries, with infectious disease being more prevalent in children compared with others in the population. Consequences of infectious disease in children may have significant economic and social impact beyond the direct effects of the disease on the health of the child; including absence from school, transmission of infectious disease to other pupils, staff, and family members, and time off work for parents/guardians. Reduction of the transmission of infectious disease between children at schools could be an effective way of reducing the community incidence of infectious disease. Alcohol based no-rinse hand sanitisers provide an alternative hand cleaning technology, for which there is some evidence that they may be effective in achieving this. However, very few studies have investigated the effectiveness of hand sanitisers, and importantly, the potential wider economic implications of this intervention have not been established.

Aims

The primary objective of this trial is to establish if the provision of hand sanitisers in primary schools in the South Island of New Zealand, in addition to an education session on hand hygiene, reduces the incidence rate of absence episodes due to illness in children. In addition, the trial will establish the cost-effectiveness and conduct a cost-benefit analysis of the intervention in this setting.

Methods/Design

A cluster randomised controlled trial will be undertaken to establish the effectiveness and cost-effectiveness of hand sanitisers. Sixty-eight primary schools will be recruited from three regions in the South Island of New Zealand. The schools will be randomised, within region, to receive hand sanitisers and an education session on hand hygiene, or an education session on hand hygiene alone. Fifty pupils from each school in years 1 to 6 (generally aged from 5 to 11 years) will be randomly selected for detailed follow-up about their illness absences, providing a total of 3400 pupils. In addition, absence information will be collected on all children from the school rolls. Investigators not involved in the running of the trial, outcome assessors, and the statistician will be blinded to the group allocation until the analysis is completed.

Trial registration

ACTRN12609000478213

Multiple micronutrient supplementation for improving cognitive performance in children: systematic review of randomized controlled trials

BACKGROUND

Although multiple micronutrient interventions have been shown to benefit children's intellectual development, a thorough evaluation of the totality of evidence is currently lacking to direct public health policy.

OBJECTIVE

This study aimed to systematically review the present literature and to quantify the effect of multiple micronutrients on cognitive performance in schoolchildren.

METHODS

The Institute for Scientific Information Web of Knowledge and local medical databases were searched for trials published from 1970 to 2008. Randomized controlled trials that investigated the effect of > or =3 micronutrients compared with placebo on cognition in healthy children aged 0-18 y were included following protocol. Data were extracted by 2 independent researchers. The cognitive tests used in the trials were grouped into several cognitive domains (eg, fluid and crystallized intelligence), and pooled effect size estimates were calculated per domain. Heterogeneity was explored through sensitivity and meta-regression techniques.

RESULTS

Three trials were retrieved in children aged <5 y, and 17 trials were retrieved in children aged 5-16 y. For the older children, pooled random-effect estimates for intervention were 0.14 SD (95% CI: -0.02, 0.29; P = 0.083) for fluid intelligence and -0.03 SD (95% CI: -0.21, 0.15; P = 0.74) for crystallized intelligence, both of which were based on 12 trials. Four trials yielded an overall effect of 0.30 SD (95% CI: 0.01, 0.58; P = 0.044) for academic performance. For other cognitive domains, no significant effects were found.

CONCLUSIONS

Multiple micronutrient supplementation may be associated with a marginal increase in fluid intelligence and academic performance in healthy schoolchildren but not with crystallized intelligence. More research is required, however, before public health recommendations can be given.

Provision of a school snack is associated with vitamin B-12 status, linear growth, and morbidity in children from Bogota, Colombia

In 2004, Bogotá's Secretary of Education (SED) initiated a snack program in public primary schools. A midmorning food ration was provided free of charge to children to supplement 30 and 50% of their daily requirements of energy and iron, respectively. The purpose of this study, an observational investigation of 3202 children ages 5-12 y, was to examine whether the snack program improved children's nutritional and health status. We measured micronutrient levels (plasma ferritin and vitamin B-12, and erythrocyte folate), anthropometry, and reported morbidity during the first semester of the 2006 school year. After adjusting for socioeconomic status and other school interventions, children at schools receiving the snack (n = 1803) had greater increases in plasma vitamin B-12 (42 pmol/L; P < 0.0001) from baseline to 3 mo of follow-up than children at schools not receiving the snack (n = 1399). They also experienced a smaller decrease in height-for-age Z-scores than children who did not receive the snack (P = 0.001). Provision of the SED snack was associated with significantly fewer reported days with morbidity symptoms (e.g. cough with fever, diarrhea with vomiting), 44% fewer doctor visits (P = 0.02), and 23% fewer days of school absenteeism (P = 0.03). The snack was not related to ferritin or folate levels. In conclusion, provision of a school-administered snack was related to improved vitamin B-12 status and linear growth and decreased reported morbidity. Although provision of the snack was not related to BMI changes over a 4-mo period, snack components such as candy and sugar-sweetened beverages should be replaced with healthier options, as the rates of child overweight in Colombia are not negligible.

Effect of fortification with multiple micronutrients and n-3 fatty acids on growth and cognitive performance in Indian schoolchildren: the CHAMPION (Children's Health and Mental Performance Influenced by Optimal Nutrition) Study

BACKGROUND

Fortification with multiple micronutrients has been shown to improve growth and cognitive performance among children in developing countries, but it is unknown whether higher concentrations are more effective than lower concentrations.

OBJECTIVE

We compared the effect of 2 different concentrations of a combination of micronutrients and n-3 (omega-3) fatty acids on indicators of growth and cognitive performance in low-income, marginally nourished schoolchildren in Bangalore, India.

DESIGN

In a 2-by-2 factorial, double-blind, randomized controlled trial, 598 children aged 6-10 y were individually allocated to 1 of 4 intervention groups to receive foods fortified with either 100% or 15% of the Recommended Dietary Allowance of micronutrients in combination with either 900 mg alpha-linolenic acid plus 100 mg docosahexaenoic acid or 140 mg alpha-linolenic acid for 12 mo. Anthropometric and biochemical assessments were performed at baseline and 12 mo. Cognitive performance was measured at baseline and at 6 and 12 mo.

RESULTS

The high micronutrient treatment significantly improved linear growth at 12 mo (0.19 cm; 0.01, 0.36) and short-term memory at 6 mo (0.11 SD; 0.01, 0.20) and was less beneficial on fluid reasoning at 6 (-0.10 SD; -0.17, -0.03) and 12 (-0.12 SD; -0.20, -0.04) mo than was the low micronutrient treatment, whereas no differences were observed on weight, retrieval ability, cognitive speediness, and overall cognitive performance. No significant differences were found between the n-3 treatments.

CONCLUSIONS

The high micronutrient treatment was more beneficial for linear growth than was the low micronutrient treatment. However, with some small differential effects, higher micronutrient concentrations were as effective as lower concentrations on cognitive performance. This trial was registered at clinicaltrials.gov as NCT00467909.

Impact of Zinc Fortification on Zinc Nutrition

Food fortification is increasingly recognized as an effective approach to improve a population's micronutrient status. The present report provides a critical review of the scientific evidence currently available on the impact of zinc fortification on zinc nutrition.

The available studies clearly show that zinc fortification can increase dietary zinc intake and total daily zinc absorption. Most absorption studies also indicate that adding zinc to food does not adversely affect the absorption of other minerals, such as iron. Despite the positive effect of zinc fortification on total zinc absorption, only a few studies have found positive impacts of zinc fortification on serum zinc concentrations or functional indicators of zinc status. The reasons for these inconsistent results are uncertain but may relate to the choice of food vehicles, the age group and zinc status of the study populations, or particular aspects of the study design. Thus, additional research is needed to determine the impact of zinc fortification, with or without other micronutrients, in populations at risk for zinc deficiency.

Because of the benefits of increasing intake in populations at high risk for zinc deficiency, the documented increase in total zinc absorption that occurs following zinc fortification, the absence of any adverse effects, and the relatively low cost of adding zinc, public health planners should consider including zinc in mass and targeted fortification programs in such populations. Because of the limited available information on program impact, it will be important to evaluate the outcomes of such programs.

Oral zinc for treating diarrhoea in children

BACKGROUND

Diarrhoea causes around two million child deaths annually. Zinc supplementation could help reduce the duration and severity of diarrhoea, and is recommended by the World Health Organization and UNICEF.

OBJECTIVES

To evaluate oral zinc supplementation for treating children with acute or persistent diarrhoea.

SEARCH STRATEGY

In November 2007, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library 2007, Issue 4), MEDLINE, EMBASE, LILACS, CINAHL, mRCT, and reference lists. We also contacted researchers.

SELECTION CRITERIA

Randomized controlled trials comparing oral zinc supplementation (>/= 5 mg/day for any duration) with placebo in children aged one month to five years with acute or persistent diarrhoea, including dysentery.

DATA COLLECTION AND ANALYSIS

Both authors assessed trial eligibility and methodological quality, extracted and analysed data, and drafted the review. Diarrhoea duration and severity were the primary outcomes. We summarized dichotomous outcomes using risk ratios (RR) and continuous outcomes using mean differences (MD) with 95% confidence intervals (CI). Where appropriate, we combined data in meta-analyses (using the fixed- or random-effects model) and assessed heterogeneity.

MAIN RESULTS

Eighteen trials enrolling 6165 participants met our inclusion criteria. In acute diarrhoea, zinc resulted in a shorter diarrhoea duration (MD -12.27 h, 95% CI -23.02 to -1.52 h; 2741 children, 9 trials), and less diarrhoea at day three (RR 0.69, 95% CI 0.59 to 0.81; 1073 children, 2 trials), day five (RR 0.55, 95% CI 0.32 to 0.95; 346 children, 2 trials), and day seven (RR 0.71, 95% CI 0.52 to 0.98; 4087 children, 7 trials). The four trials (1458 children) that reported on diarrhoea severity used different units and time points, and the effect of zinc was less clear. Subgroup analyses by age (trials with only children aged less than six months) showed no benefit with zinc. Subgroup analyses by nutritional status, geographical region, background zinc deficiency, zinc type, and study setting did not affect the results' significance. Zinc also reduced the duration of persistent diarrhoea (MD -15.84 h, 95% CI -25.43 to -6.24 h; 529 children, 5 trials). Few trials reported on severity, and results were inconsistent. No trial reported serious adverse events, but vomiting was more common in zinc-treated children with acute diarrhoea (RR 1.71, 95% 1.27 to 2.30; 4727 children, 8 trials).

AUTHORS' CONCLUSIONS

In areas where diarrhoea is an important cause of child mortality, research evidence shows zinc is clearly of benefit in children aged six months or more.