Background: Autism spectrum disorder (ASD) is a public health problem and has a prevalence of 0.6%–1.7% in children. As well as psychiatric symptoms, dysbiosis and gastrointestinal comorbidities are also frequently reported. The gut–brain microbiota axis suggests that there is a form of communication between microbiota and the brain underlying some neurological disabilities. The aim of this study is to describe and compare the composition of gut microbiota in children with and without ASD. Methods: Electronic databases were searched as far as February 2020. Meta-analyses were performed using RevMan5.3 to estimate the overall relative abundance of gut bacteria belonging to 8 phyla and 17 genera in children with ASD and controls. Results: We included 18 studies assessing a total of 493 ASD children and 404 controls. The microbiota was mainly composed of the phyla Bacteroidetes, Firmicutes, and Actinobacteria, all of which were more abundant in the ASD children than in the controls. Children with ASD showed a significantly higher abundance of the genera Bacteroides, Parabacteroides, Clostridium, Faecalibacterium, and Phascolarctobacterium and a lower percentage of Coprococcus and Bifidobacterium. Discussion: This meta-analysis suggests that there is a dysbiosis in ASD children which may influence the development and severity of ASD symptomatology. Further studies are required in order to obtain stronger evidence of the effectiveness of pre- or probiotics in reducing autistic behaviors.

Anemia affects 1.62 billion people worldwide. Latin America and the Caribbean (LAC) comprise several developing countries where children are a population at risk. This systematic review and meta-analysis aimed to estimate the prevalence of anemia in this population. Electronic databases, reference lists, and websites of health ministries were searched until December 2018. Stratified analyses were performed using RevMan5.3 to estimate the overall prevalence of anemia in preschool and school-age children. The effectiveness of nutritional interventions was also evaluated. We included 61 studies from the 917 reviewed, which included 128,311 preschool- and 38,028 school-age children from 21 LAC countries. The number of anemic children was 32.93% and 17.49%, respectively, demonstrating a significant difference according to age (p < 0.01). No difference was observed by gender and only school-age children from low/very low socioeconomic status (SES) (25.75%) were more prone to anemia than those from middle SES (7.90%). It was not a concern in the Southern Cone but constituted a serious public health problem in the Latin Caribbean. Nutritional interventions reduced the prevalence from 45% to 25% (p < 0.01). Anemia is still a public health problem for children in LAC countries. National surveys should include school-age children. Further nutritional interventions are required to control anemia.

Iron deficiency and iron-deficiency anemia are the main worldwide nutritional disorders. A good level of prenatal iron is essential for the correct child neurodevelopment but this association has been poorly investigated. To gather the scientific evidence on the relation between prenatal iron status and child neurodevelopment. To emphasize the importance of personalize the dose and type of supplementation. Wide search strategy was performed in electronic databases for English language articles with no limitations as regards the language or date of publication. Additional studies were selected by hand search. The inclusion criteria were pregnant women without high-risk pregnancy and their children as study population and neurodevelopment as the main outcome. Six RCTs and 13 observational studies were included. The majority concluded that deficit or excess iron during pregnancy injures the mental and psychomotor development of child. Other authors found no association of low iron level with troubles in neurodevelopment, recommended multi-micronutrients instead of iron alone and/or showed inconsistent results. Both iron deficiency as its excess are harmful for the child neurodevelopment. The prenatal iron supplementation should be adjusted for each woman, taking into account the iron stores, some genetic mutation and other health habits.

Type 2 diabetes poses a major public health challenge. Here, we conducted a cohort study with a large sample size to determine the association of baseline serum ferritin (SF), a marker of iron status, with incident type 2 diabetes in primary healthcare patients in Catalonia, a western Mediterranean region. A total of 206,115 patients aged 35–75 years without diabetes and with available baseline SF measurements were eligible. The variables analyzed included sociodemographic characteristics, anthropometry, lifestyle, morbidity and iron status (SF, serum iron and hemoglobin). Incident type 2 diabetes during follow-up (2006–2016) was ascertained using the International Classification of Diseases, 10th edition. Cox proportional-hazards models adjusted for multiple baseline confounders/mediators were used to estimate hazard ratios (HRs). Over a median follow-up of 8.4 years, 12,371 new cases of type 2 diabetes were diagnosed, representing an incidence rate of 7.5 cases/1000 persons/year. Since at baseline, the median SF concentration was higher in subjects who developed type 2 diabetes (107.0 µg/L vs. 60.3 µg/L; p < 0.001), SF was considered an independent risk predictor for type 2 diabetes; the multivariable-adjusted HRs for incident type 2 diabetes across SF quartiles 1–4 were 1.00 (reference), 0.95 (95% CI = 0.85–1.06), 1.18 (95% CI = 1.65–1.31) and 1.51 (95% CI = 1.36–1.65), respectively. Our study suggested that higher baseline SF was significantly associated with an increased risk of new-onset type 2 diabetes in Catalan primary healthcare users, supporting the relevance of monitoring iron stores in order to improve the diagnosis and management of diabetes in clinical practice.