Adolescent girls are an important target group for micronutrient interventions particularly in Sub-Saharan Africa where adolescent pregnancy and micronutrient deficiencies are common. When consumed in sufficient amounts and at levels appropriate for the population, fortified foods may be a useful strategy for this group, but little is known about their effectiveness and timing (regarding menarche), particularly in resource-poor environments. We evaluated the effect of consuming multiple micronutrient-fortified biscuits (MMB), sold in the Ghanaian market, 5 d/week for 26 weeks compared with unfortified biscuits (UB) on the micronutrient status of female adolescents. We also explored to what extent the intervention effect varied before or after menarche. Ten2Twenty-Ghana was a 26-week double-blind, randomised controlled trial among adolescent girls aged 10–17 years (n 621) in the Mion District, Ghana. Biomarkers of micronutrient status included concentrations of Hb, plasma ferritin (PF), soluble transferrin receptor (TfR) and retinol-binding protein (RBP), including body-iron stores. Intention-to-treat analysis was supplemented by protocol-specific analysis. We found no effect of the intervention on PF, TfR and RBP. MMB consumption did not affect anaemia and micronutrient deficiencies at the population level. MMB consumption increased the prevalence of vitamin A deficiency by 6·2 % (95 % CI (0·7, 11·6)) among pre-menarche girls when adjusted for baseline micronutrient status, age and height-for-age Z-score, but it decreased the prevalence of deficient/low vitamin A status by −9·6 % (95 % CI (−18·9, −0·3)) among post-menarche girls. Consuming MMB available in the market did not increase iron status in our study, but reduced the prevalence of deficient/low vitamin A status in post-menarcheal girls.

Vitamin A is an essential micronutrient, especially during pregnancy. We aimed to assess the prevalence of vitamin A deficiency in Brazilian women of childbearing age. We conducted a systematic review with meta-analysis of studies that assessed vitamin A deficiency in women of childbearing age following the registered protocol (CRD42020171856). Independent peer researchers selected the studies retrieved from MEDLINE, Embase, Scopus and other sources. Data from the eligible studies were extracted in pairs and assessed for methodological quality. The prevalence of vitamin A deficiency (< 0·70 µmol/l or <0·20 µg/dl) and 95 % CI was combined by meta-analysis, and heterogeneity was estimated by I 2. Out of 3610 screened records, thirty-two studies were included, which assessed 12 577 women from 1965 to 2017, mostly in maternity hospitals. Main limitations of the studies were in sample frame (30/32) and sampling method (29/32). Deficiency occurred in 13 % (95 % CI 9·4, 17·2 %; I² = 97 %) of all women and was higher in pregnant women (16·1 %; 95 % CI 5·6, 30·6 %; I² = 98 %) than non-pregnant women (12·3 %; 95 % CI 8·4, 16·8 %; I² = 96 %). The prevalence increased according to the decade, from 9·5 % (95 % CI 1·9–21·6 %; I² = 98 %) up to 1990, 10·8 % (95 % CI 7·9, 14·2 %; I² = 86 %) in the 2000s and 17·8 % (95 % CI 8·7, 29·0 %; I² = 98 %) in the 2010s. Over 10 % of Brazilian women in childbearing age were deficient in vitamin A. Higher prevalence was observed in pregnant women, and deficiency seemed to be increasing over the decades. Low representativeness of the studies, mainly based on convenience sampling that included pregnant, postpartum, lactating and non-pregnant women, as well as high heterogeneity, limits the findings.

Childhood malnutrition is known as a public health concern globally. The present study aims to assess the anthropometry and blood biochemical status of rural primary schoolchildren in Malaysia. A total of 776 children (7–11 years old) from ten rural primary schools from five states were included in this study. Nutritional outcomes were assessed based on sex, age group and school categories among the children (median age: 9 years (P25:8, P75:10)). The overall prevalence of malnutrition was 53·4 %. Vitamin A deficiency (VAD) was recorded at 20·6 and 39·8 % based on retinol and retinol-binding protein (RBP) levels, respectively. Anaemia, iron deficiency (ID), iron-deficiency anaemia (IDA) and elevated inflammation were found at 14·9, 17·9, 9·1 and 11·5 %, respectively. Malnutrition, VAD, anaemia, ID, IDA and elevated inflammation were more prevalent among Orang Asli (OA) schoolchildren compared with Non-Orang Asli schoolchildren. Higher occurrences of VAD and anaemia were also found among children aged <10 years. Retinol, RBP, α-carotene, ferritin and haemoglobin levels were lower among undernourished children. Besides, overweight/obese children exhibited a higher level of high-sensitivity C-reactive protein. Multivariate analysis demonstrated that OA school children (adjusted OR (AOR): 6·1; 95 % CI 4·1, 9·0) and IDA (AOR: 3·6; 95 % CI 1·9, 6·6) were associated with stunting among this population. The present study revealed that malnutrition, micronutrient deficiencies and anaemia are prevalent among rural primary schoolchildren in Malaysia, especially those from OA schools and younger age children (<10 years). Hence, more appropriate and targeted measures are needed to improve the nutritional status of these children.

India is coming to grips with a stage of nutrition transition. According to the Food Safety and Standards Authority of India (FSSAI), preventable micronutrient deficiency is arising public health precedence in India. However, the foremost public health concern is the lack of national prevalence data. The present study was carried out to estimate the pooled age-wise prevalence of six preventable micronutrient deficiencies (vitamin A, vitamin B12, vitamin D, iron, iodine and folic acid) in India. A systematic review was carried out on PubMed and Global Index Medicus databases using the Boolean search strategy. Statistical analyses were done using R software, version 3.6. 2. PRISMA guidelines were strictly adhered to during the review. A preliminary literature search yielded 4302 articles; however, 270 original research articles were found eligible to be included in quantitative synthesis. The estimated overall prevalence was 17 % [95 % confidence interval (CI) 0⋅07, 0⋅26] for iodine deficiency, 37 % (95 % CI 0⋅27, 0⋅46) for folic acid deficiency, 54 % (95 % CI 0⋅49, 0⋅59) for iron deficiency, 53 % (95 % CI 0⋅41, 0⋅64) for vitamin B12 deficiency, 19 % (95 % CI 0⋅09, 0⋅29) for vitamin A deficiency and 61 % (95 % CI 0⋅07, 0⋅26) for vitamin D with high heterogeneity. We classified the population into infants (0–5 years), adolescents (<18 years), adults (>18 years) and pregnant women. Iron deficiency was most prevalent (61 %) in pregnant women. The results of the present study reinforce the data on micronutrient deficiency in India and warrant the immediate need for further active public health interventions to address these deficiencies. The study is registered with PROSPERO (CRD42020205043).

Countries are increasingly transitioning from event-based vitamin A supplementation (VAS) distribution to delivery through routine health system contacts, shifting also to administrative, electronic-based monitoring tools, a process that brings certain limitations affecting the quality of administrative VAS coverage. At present, there is no standardised methodology for measuring the coverage of VAS delivered through routine health services. To address this gap, we conducted a systematic review of the literature to identify and recommend methods to measure VAS coverage, with the aim of providing guidance to countries on the collection of consistent data for planning, monitoring and evaluating VAS programmes integrated into routine health systems. We searched the PubMed®, Embase®, Scopus, Google Scholar and World Health Organization (WHO) Global Index Medicus databases for studies published from 1 January 2000 to 1 January 2021, reporting original data on VAS coverage and methodologies used for measurement. We screened 2371 original titles and abstracts, assessed twenty-seven full-text articles and ultimately included eighteen studies. All but two studies used a coverage cluster survey (CCS) design to measure VAS coverage, adapting the WHO Vaccination Coverage Cluster Surveys methodology, by modifying sample size and sampling parameters. Annual two-dose VAS coverage was reported from only four studies. Until electronic-based systems to collect and analyse VAS data are equipped to measure routine two-dose VAS coverage using administrative data, CCSs that comply with the 2018 WHO Vaccination Coverage Cluster Surveys Reference Manual represent the gold-standard method for effective VAS programme monitoring.

Biofortified yellow cassava has been developed to alleviate vitamin A deficiency. We examined the potential contribution of yellow cassava to total retinol activity equivalent (RAE) intake if replacing white by yellow cassava among pre-school Nigerian children. Dietary intake was assessed as part of a randomised controlled trial. Pre-schoolchildren (n 176) were randomly assigned to receive either white cassava (WC) or yellow cassava (YC) for 17 weeks. Dietary intake assessments were conducted during the intervention and 1 month after, when children had resumed their habitual diet. Differences in RAE intake between groups and time points were compared using a linear mixed model regression analysis. During intervention, median RAE intake was 536 µg/d in the YC group and 301 µg/d in the WC group (P < 0·0001). YC contributed approximately 40 % to total RAE intake. Of the children, 9 % in the YC group and 29 % in the WC group had RAE intake below the Estimated Average Requirement. After intervention, median RAE intake was 300 µg/d and did not differ between intervention groups (P = 0·5). The interaction effect of group and time showed a 37 % decrease in RAE intake in the YC group after the intervention (Exp(β) = 0·63; 95 % CI 0·56, 0·72). If WC was replaced by YC after intervention, the potential contribution of YC to total RAE intake was estimated to be approximately 32 %. YC increased total RAE intake and showed a substantially lower inadequacy of intake. It is therefore recommended as a good source of provitamin A in cassava-consuming regions.

The present study investigated the effects of dietary vitamin A on immune function in the proximal intestine (PI), mid intestine (MI) and distal intestine (DI) of young grass carp (Ctenopharyngodon idella). Fish were fed graded levels of dietary vitamin A for 10 weeks, and then a challenge test using an injection of Aeromonas hydrophila was conducted for 14 d. The results showed that, compared with the optimum vitamin A level, vitamin A deficiency significantly decreased fish growth performance, increased enteritis morbidity, decreased intestinal innate humoral immune response and aggravated intestinal inflammation. However, liver-expressed antimicrobial peptide 2A/B mRNA in the DI and IL-6, IL-17D, IL-10, transforming growth factor (TGF)-β1 and TGF-β2 mRNA in the PI were not affected by vitamin A levels. Meanwhile, vitamin A deficiency disturbed inflammatory cytokines in the PI, MI and DI, which might be partly linked to p38 mitogen-activated protein kinase (p38MAPK) signalling and NF-κB canonical signalling pathway (IκB kinase β (IKKβ), IKKγ, inhibitor of κBα, NF-κB p65 and c-Rel) rather than NF-κB non-canonical signalling pathway (NF-κB p52 and IKKα). However, the signalling molecules NF-κB p65 and p38MAPK did not participate in regulating cytokines in the PI. These results suggested that vitamin A deficiency decreased fish growth and impaired intestinal immune function, and that different immune responses in the PI, MI and DI were mediated partly by NF-κB canonical signalling and p38MAPK signalling pathways. On the basis of percentage of weight gain, to protect fish against enteritis morbidity and acid phosphatase activity, the optimum dietary vitamin A levels were estimated to be 0·664, 0·707 and 0·722 mg /kg, respectively.

This paper provides a comprehensive review of the current situation regarding micronutrient deficiencies among children and women in Bangladesh. This review also discusses the successes and current challenges of existing intervention programmes. Data from nationally representative and selected small surveys since the 1980s that have reported on the status of at least one micronutrient in children and/or women have been examined. National policy documents/reports on existing interventions have been analysed. While the severity of various micronutrient deficiencies has declined since the 1980s, a significant proportion of preschool-age children remains with deficiencies in vitamin A (20·5 %), Zn (44·5 %) and vitamin D (39·6 %); about one-third of these children are anaemic, and 10·7 % of the children are Fe deficient. A high proportion of non-pregnant and non-lactating women is deficient in Zn (57 %) and I (42 %), while one-quarter of women live with anaemia and vitamin B12 and vitamin D (21 %) deficiencies. Nearly one-half of the pregnant and lactating women are anaemic. Suboptimal diets, poor hygiene, infection and infestation are identified as some of the key factors associated with high levels of deficiencies. Multiple approaches and interventions are being supported, and while some notable progress has been achieved, significant challenges continue, including those related to coverage, quality and compliance. It is concluded that although current intervention programmes have made some progress in controlling the severe deficiencies, micronutrient deficiencies in Bangladesh remain a considerable problem. More well-integrated approaches for strengthening the existing intervention programmes are needed. In addition, new intervention strategies for alleviating and preventing specific micronutrient deficiencies are recommended.

The aim of this study was to explore the effect of single-dose albendazole and vitamin A intervention on the anaemic status and Fe metabolism of pre-school children. This study was a randomised, placebo-controlled and double-blinded intervention trial. All eligible anaemic pre-school children were randomly divided into three groups: group 1 received no intervention, which served as the control group, group 2 received 400 mg single-dose albendazole administration and group 3 received a 60000 μg vitamin A capsule combined with 400 mg single-dose albendazole at the beginning of the study. The follow-up period was for 6 months. Anthropometry and biochemical index about Fe metabolism were measured before and after intervention. A total of 209 pre-school anaemic children were randomly divided into three intervention groups (sixty-four, sixty-two and sixty for groups 1, 2 and 3, respectively). The mean age of the children in the study was 4·4 (sd 0·7) years and 50·5 % of the children were female (94/186). After a follow-up period of 6 months, the levels of serum retinol, ferritin, transferrin receptor-ferritin index and body total Fe content of children in group 3 were significantly higher compared with children in groups 1 and 2 (P<0·05). Moreover, the proportion of vitamin A deficiency, marginal vitamin A deficiency and Fe deficiency among children in group 3 were markedly lower compared with children in groups 1 and 2 (P<0·05). Albendazole plus vitamin A administration showed more efficacy on the improvement of serum retinol and Fe metabolic status.

As WHO recommends vitamin A supplementation (VAS) at vaccination contacts after age 6 months, many children receive VAS together with measles vaccine (MV). We aimed to investigate the immunological effect of VAS given with MV. Within a randomised placebo-controlled trial investigating the effect on overall mortality of providing VAS with vaccines in Guinea-Bissau, we conducted an immunological sub-study of VAS v. placebo with MV, analysing leucocyte counts, whole blood in vitro cytokine production, vitamin A status and concentration of C-reactive protein (CRP). VAS compared with placebo was associated with an increased frequency of CRP≥5 mg/l (28 v. 12 %; P=0·005). Six weeks after supplementation, VAS had significant sex-differential effects on leucocyte, lymphocyte, monocyte and basophil cell counts, decreasing them in males but increasing them in females. Mainly in females, the effect of VAS on cytokine responses differed by previous VAS: in previous VAS recipients, VAS increased the pro-inflammatory and T helper cell type 1 (Th1) cytokine responses, whereas VAS decreased these responses in previously unsupplemented children. In previous VAS recipients, VAS was associated with increased IFN-γ responses to phytohaemagglutinin in females (geometric mean ratio (GMR): 3·97; 95 % CI 1·44, 10·90) but not in males (GMR 0·44; 95 % CI 0·14, 1·42); the opposite was observed in previously unsupplemented children. Our results corroborate that VAS provided with MV has immunological effects, which may depend on sex and previous VAS. VAS may increase the number of leucocytes, but also repress both the innate and lymphocyte-derived cytokine responses in females, whereas this repression may be opposite if the females have previously received VAS.