UNASSIGNED: Vitamin A deficiency, iodine deficiency, and protein-energy malnutrition are prevalent malnutrition issues that disproportionately affect low-income countries and pose significant risks to the health and development of children and adolescents. This study offers a detailed examination of these deficiencies\' prevalence trends and gender and regional variations using Global Burden of Disease Study data from 1990 to 2019. It also assesses the specific impact on various age groups, providing essential insights for targeted health interventions and policy-making.
UNASSIGNED: Data spanning from 1990 to 2019 on Vitamin A deficiency, iodine deficiency, and protein-energy malnutrition were extracted from the 2019 Global Burden of Disease Study. Age-Standardized Incidence Rates (ASR) were computed by gender, region, and etiology, utilizing the estimated annual percentage change (EAPC) to assess temporal trends.
UNASSIGNED: In 2019, Central Sub-Saharan Africa had the highest prevalence of Vitamin A deficiency, particularly among males, and iodine deficiency peaked in the same region for both genders. South Asia had the highest incidence of protein-energy malnutrition for both genders. Regions with a low Socio-Demographic Index (SDI) showed lower ASR for these deficiencies. Notably, Cameroon, Equatorial Guinea, and Maldives recorded the highest ASR for vitamin A deficiency, iodine deficiency, and protein-energy malnutrition, respectively. The declining ASR trend for vitamin A deficiency, especially among males, suggests effective interventions. East Asia saw a significant increase in iodine deficiency ASR from 1990 to 2019, particularly among women, requiring targeted interventions. The rising ASR of protein-energy malnutrition in several regions, especially among men, raises concerns. Vitamin A deficiency primarily affected children and adolescents, iodine deficiency predominantly impacted adolescents and young adults, and protein-energy malnutrition was chiefly observed among children under 5 years old. These findings underscore the necessity for tailored interventions considering age-specific nutritional needs and challenges.

BACKGROUND: This study aimed to investigate the impact of Vitamin A (VA) on intestinal glucose metabolic phenotypes.
METHODS: Male C57BL/6 mice were randomized assigned to a VA-normal diet (VAN) or a VA-deficient diet (VAD) for 12 weeks. After12 weeks, the VAD mice were given 30 IU/g/d retinol for 10 days and VAN diet (VADN) for 10 weeks. By using glucose tolerance tests, immunofluorescence staining, quantitative polymerase chain reaction, siRNA transduction, and enzyme-linked immunosorbent assay, the glucose metabolic phenotypes as well as secretory function and intracellular hormone changes of STC-1 were assessed.
RESULTS: VAD mice showed a decrease of glucose-stimulated insulin secretion and a loss of intestinal glucagon-like peptide-1 (GLP-1) expression. Through reintroducing dietary VA to VAD mice, the intestinal VA levels, GLP-1 expression and normal glucose can be restored. The incubation with retinol increased VA signaling factors expression within STC-1 cells, especially retinoic acid receptor β (RARβ). The activation of RARβ restored intracellular incretin hormone synthesis and secretory function.
CONCLUSIONS: VA deficiency leads to an imbalance of intestinal glucose metabolic phenotypes through a mechanism involving RARβ signaling pathway, suggesting a new method to achieve the treatment for VAD induced glucose metabolism impairment.

According to global prevalence analysis studies, acute upper respiratory tract infections (URTIs) are the most common acute infectious disease in children, especially in preschool children. Acute URTIs lead to an economic burden on families and society. Vitamin A refers to the fat-soluble compound all-trans-retinol and also represents retinol and its active metabolites. Vitamin A interacts with both the innate immune system and the adaptive immune system and improves the host\'s defences against infections. Correlation studies show that serum retinol deficiency was associated with a higher risk of respiratory tract infections. Therefore, vitamin A supplementation may be important in preventing acute URTIs.
To assess the effectiveness and safety of vitamin A supplements for preventing acute upper respiratory tract infections in children up to seven years of age.
We searched CENTRAL, MEDLINE, Embase, the Chinese Biomedical Literature Database, and two trial registration platforms to 8 June 2023. We also checked the reference lists of all primary studies and reviewed relevant systematic reviews and trials for additional references. We imposed no language or publication restrictions.
We included randomised controlled trials (RCTs), which evaluated the role of vitamin A supplementation in the prevention of acute URTIs in children up to seven years of age.
We used the standard methodological procedures expected by Cochrane.
We included six studies (27,351 participants). Four studies were RCTs and two were cluster-RCTs. The included studies were all conducted in lower-middle-income countries (two in India, two in South Africa, one in Ecuador, and one in Haiti). Three studies included healthy children who had no vitamin A deficiency, one study included children born to HIV-infected women, one study included low-birthweight neonates, and one study included children in areas with a high local prevalence of malnutrition and xerophthalmia. In two studies, vitamin E was a co-treatment administered in addition to vitamin A. We judged the included studies to be at either a high or unclear risk of bias for random sequence generation, incomplete outcome data, and blinding. Primary outcomes Six studies reported the incidence of acute URTIs during the study period. Five studies reported the number of acute URTIs over a period of time, but there was population heterogeneity and the results were presented in different forms, therefore only three studies were meta-analysed. We are uncertain of the effect of vitamin A supplementation on the number of acute URTIs over two weeks (risk ratio (RR) 1.00, 95% confidence interval (CI) 0.92 to 1.09; I2 = 44%; 3 studies, 22,668 participants; low-certainty evidence). Two studies reported the proportion of participants with an acute URTI. We are uncertain of the effect of vitamin A supplementation on the proportion of participants with an acute URTI (2 studies, 15,535 participants; low-certainty evidence). Only one study (116 participants) reported adverse events. No infant in either the placebo or vitamin A group was found to have feeding difficulties (failure to feed or vomiting), a bulging fontanelle, or neurological signs before or after vitamin A administration (very low-certainty evidence). Secondary outcomes Two studies (296 participants) reported the severity of subjective symptoms, presented by the mean duration of acute URTI. Vitamin A may have little to no effect on the mean duration of acute URTI (very low-certainty evidence).
The evidence for the use of vitamin A supplementation to prevent acute URTI is uncertain, because population, dose and duration of interventions, and outcomes vary between studies. From generally very low- to low-certainty evidence, we found that there may be no benefit in the use of vitamin A supplementation to prevent acute URTI in children up to seven years of age. More RCTs are needed to strengthen the current evidence. Future research should report over longer time frames using validated tools and consistent reporting, and ensure adequate power calculations, to allow for easier synthesis of data. Finally, it is important to assess vitamin A supplementation for preschool children with vitamin A deficiency.

BACKGROUND: Nutritional deficiencies remain serious medical and public health issues worldwide, especially in children. This study aims to analyze cross-country inequality in four common nutritional deficiencies (protein-energy malnutrition, dietary iron deficiency, vitamin A deficiency and iodine deficiency) among children from 1990 to 2019 based on Global Burden of Disease (GBD) 2019 data.
METHODS: Prevalence and disability-adjusted life years (DALYs) data as measures of four nutritional deficiency burdens in people aged 0 to 14 years were extracted from the GBD Results Tool. We analyzed temporal trends in prevalence by calculating the average annual percent change (AAPC) and quantified cross-country inequalities in disease burden using the slope index.
RESULTS: Globally, the age-standardized prevalence rates of dietary iron deficiency, vitamin A deficiency and iodine deficiency decreased, with AAPCs of -0.14 (-0.15 to -0.12), -2.77 (-2.96 to -2.58), and -2.17 (-2.3 to -2.03) from 1999 to 2019, respectively. Significant reductions in socio-demographic index (SDI)-related inequality occurred in protein-energy malnutrition and vitamin A deficiency, while the health inequality for dietary iron deficiency and iodine deficiency remained basically unchanged. The age-standardized prevalence and DALY rates of the four nutritional deficiencies decreased as the SDI and healthcare access and quality index increased.
CONCLUSIONS: The global burden of nutritional deficiency has decreased since 1990, but cross-country health inequalities still exist. More efficient public health measures are needed to reduce disease burdens, particularly in low-SDI countries/territories.

UNASSIGNED: Vitamin A deficiency (VAD) is a leading global nutritional concern, ranking among the top four major nutritional deficiencies worldwide. The prevalence of VAD is unevenly distributed across various regions, both within China and globally.
UNASSIGNED: The report adds valuable insights into the vitamin A nutritional status of rural students aged 6-17 years who participated in the Nutrition Improvement Programme for Rural Compulsory Education Students (NIPRCES). Over the decade from 2012 to 2021, there was a modest improvement in vitamin A status. The prevalence of VAD and sub-clinical VAD (SVAD) declined as the students aged. Throughout the majority of the survey years, the incidence of VAD was higher among males and western regions compared to females and central regions, respectively.
UNASSIGNED: A comprehensive approach, incorporating dietary diversification, nutrition education, and food fortification, should be implemented to prevent VAD and SVAD especially in males, younger children and children in western areas.

UNASSIGNED: Recurrent respiratory tract infections (RRTIs) are common in children and its development might be associated with vitamin A deficiency according to recent research. The aim of this study was to understand the relation between vitamin A status and RRTIs in children, and the relation between dietary intake of vitamin A and RRTIs.
UNASSIGNED: 2,592 children aged 0.5-14 years from Heilongjiang province of China participated in the survey. The RRTI group consisted of 1,039 children with RRTIs, while 1,553 healthy children were included in the control group. The levels of serum vitamin A were determined by high performance liquid chromatography (HPLC); dietary information was collected with the Food Frequency Questionnaire (FFQ).
UNASSIGNED: Serum vitamin A concentration in the RRTI group was significantly lower than that in the control group (0.27 ± 0.09 mg/L vs. 0.29 ± 0.09 mg/L) (P < 0.01). The levels of vitamin A was obviously associated with the occurrence of RRTIs. The odds ratios (ORs) for vitamin A insufficiency and deficiency were 1.32 (95% CI: 1.09-1.60) and 1.95 (95% CI: 1.50-2.55) respectively; whereas 1.48 (95% CI: 1.13-1.94) and 6.51 (95% CI: 4.18-10.14) respectively, in children with current respiratory tract infection (RTI) symptoms. Even an insufficient intake of animal liver was associated with lower RRTIs [OR: 0.45 (95% CI: 0.38-0.53)], while only an excessive intake of meat had the same effect [OR: 0.85 (95% CI: 0.68-1.06)].
UNASSIGNED: Low serum vitamin A concentration was associated with high incidence of RRTIs in children in northeast China; low serum vitamin A concentrations and the current RTI symptoms were associated with the development of RRTIs; and low intakes of vitamin A-rich foods were also associated with the development of RRTIs.

Acute respiratory distress syndrome (ARDS) is a major disease that threatens the life and health of neonates. Vitamin A (VA) can participate in early fetal lung development and affect lung immune function. Researches revealed that the serum VA level in premature infants with ARDS was lower than that in premature infants without ARDS of the same gestational age, and premature infants with VA deficiency (VAD) were more likely to develop ARDS. Moreover, the VA levels can be used as a predictor of the development and severity of neonatal ARDS. However, the critical question here is; Does ARDS develop due to VAD in these systemic diseases? Or does ARDS develop because these diseases cause VAD? We hypothesize that VAD may aggravate neonatal ARDS by affecting immunity, metabolism, barriers and other pathways. In this article, we used multiomics analysis to find that VAD may aggravate ARDS mainly through the Fc epsilon RI signaling pathway, the HIF-1 signaling pathway, glutathione metabolism, and valine, leucine and isoleucine degradation signaling pathways, which may provide the molecular pathogenic mechanism behind the pathology of VAD-aggravated ARDS and can also provide potential molecular targets for subsequent research on ARDS.

The Keratoconus (KC) is a corneal ectatic disease with unclear etiology. There are increasing studies that reported its association with a variety of inflammatory mechanisms. Vitamin A(VA) is an important nutrient related to inflammation regulation, and its deficiency may cause abnormalities of the ocular surface. However, the proportion of Vitamin A deficiency(VAD) was found surprisingly high among KC patients in our clinic practice. The aim of this study is to explore the effects of VAD on the transcriptome of corneas with the help of the VAD murine model and transcriptomics techniques. Blood samples of KC patients and non-KC controls (NC) were collected and the serum VA concentrations were measured and analyzed. A total of 52 NC and 39 KC were enrolled and the comparison of serum VA showed that the proportion of VAD in KC patients was 48.7% versus 1.9% in NC group. The further analysis of gender differences showed the proportion of VAD in female KC was 88.9% versus 36.7% in KC male patients. To explore the influence of VAD on cornea, the VAD mice fed with VAD diets were used. The RNA sequencing was employed to compare the corneal transcriptomic characteristics between the VAD female mice, NC female mice, VAD male mice and NC male mice. The transcriptome analysis revealed that the upregulated differential genes were mainly enriched in the immune response related pathways in VAD female mice versus NC female mice, especially the genes of JAK-STAT signaling pathway. The downstream molecules of JAK-STAT pathway were also significant after corneal mechanical scratching in female VAD mice. While, the differential genes between VAD male mice and NC male mice were estrogen signaling pathway instead of JAK-STAT pathway. This study indicates that VAD affects the transcriptomics of murine cornea with gender differences, which specifically affects the inflammatory status of the female murine cornea.

Vitamin A (VA) plays an essential role in modulating both the gut microbiota and gut barrier function. Short-chain fatty acids (SCFAs), as metabolites of the gut microbiota, protect the physiological intestinal barrier; however, they are compromised when VA is deficient. Thus, there is an urgent need to understand how and which SCFAs modulate colonic epithelial barrier integrity in VA deficiency (VAD). Herein, compared with normal VA rats (VAN), at the beginning of pregnancy, we confirmed that the colonic desmosome junction was impaired in the VAD group, and the amounts of acetate, propionate, and butyrate declined because of the decreased abundance of SCFA-producing bacteria (Romboutsia, Collinsella, and Allobaculum). The differentially expressed genes correlated with the gut barrier and the histone deacetylase complex between the VAD and VAN groups were enriched by RNA sequencing. In the VAD group, the expression levels of colonic CEA cell adhesion molecule 1 (CEACAM1) were down-regulated, and the levels of histone deacetylase 1 (HDAC1) and HDAC3 were up-regulated. Intriguingly, the above changes in the VAD groups were rescued by VA supplementation in the early postnatal period. Further study indicated that in Caco-2 cells, butyrate treatment significantly repressed the enrichment of HDAC3 on the promoter of the CEACAM1 gene to induce its expression. Our findings support that butyrate intervention can alleviate the impairment of colonic barrier function caused by VAD, and timely postnatal VA intervention may reverse the damage caused by VAD on gut barrier integrity during pregnancy.

UNASSIGNED: Vitamin A deficiency (VAD) is widely recognised as a major public health concern in low- and middle-income countries (LMICs). Despite various interventions implemented in many countries, a lack of reliable data is hindering progress. We aimed to consolidate available data and quantify estimates of the prevalence of VAD among children ≤18 years in LMICs.
UNASSIGNED: We searched PubMed, Medline and Embase for studies reported the prevalence of VAD or marginal (m)VAD among children. A multilevel mixed-effects meta-regression approach was applied to establish the regression models for VAD and mVAD prevalence. The total numbers of children affected by VAD and mVAD in LMICs in 2019 were separately calculated from the estimated age- and socio-demographic index (SDI)-specific prevalence with their corresponding United Nations Population Division populations projections. We estimated areas of significant public health concern in 165 LMICs using the lower confidence interval (CI) of VAD prevalence.
UNASSIGNED: A total of 116 articles from 40 LMICs were retained. In 2019, VAD and mVAD affected 333.95 million (95% CI = 253.00-433.74) and 556.13 million (95% CI = 388.83-767.94) children and adolescents in 165 LMICs, respectively, corresponding to a prevalence of 14.73% (95% CI = 11.16-19.14) and 24.54% (95% CI = 17.15-33.88). The prevalence of both VAD and mVAD was the highest in children aged 0-5 years at 19.53% (95% CI = 15.03-24.91) and 28.22% (95% CI = 20.00-38.24), respectively, with both steadily decreasing to 10.09% (95% CI = 7.44-13.50) and 20.76% (95% CI = 14.16-29.50) in adolescents aged 13-18 years. The prevalence of VAD was significantly higher in the low SDI region at 29.67% (95% CI = 22.67-37.53) compared to 5.17% (95% CI = 3.14-8.43) estimated in the high-middle SDI region. 68 of the 165 LMICs (41.21%) were classified as areas of moderate to severe VAD public health significance.
UNASSIGNED: VAD continues to pose a significant public health concern in many low-income settings. Development in LMICs is a crucial factor for VAD, with a disproportionately higher burden in low SDI regions.
UNASSIGNED: This study protocol was registered with PROSPERO, CRD42020220654.