Anxiety and eating disorders produce a physiological imbalance that triggers alterations in the abundance and composition of gut microbiota. Moreover, the gut–brain axis can be altered by several factors such as diet, lifestyle, infections, and antibiotic treatment. Diet alterations generate gut dysbiosis, which affects immune system responses, inflammation mechanisms, the intestinal permeability, as well as the production of short chain fatty acids and neurotransmitters by gut microbiota, which are essential to the correct function of neurological processes. Recent studies indicated that patients with generalized anxiety or eating disorders (anorexia nervosa, bulimia nervosa, and binge-eating disorders) show a specific profile of gut microbiota, and this imbalance can be partially restored after a single or multi-strain probiotic supplementation. Following the PRISMA methodology, the current review addresses the main microbial signatures observed in patients with generalized anxiety and/or eating disorders as well as the importance of probiotics as a preventive or a therapeutic tool in these pathologies.

The perinatal period is crucial to the establishment of lifelong gut microbiota. The abundance and composition of microbiota can be altered by several factors such as preterm delivery, formula feeding, infections, antibiotic treatment, and lifestyle during pregnancy. Gut dysbiosis affects the development of innate and adaptive immune responses and resistance to pathogens, promoting atopic diseases, food sensitization, and infections such as necrotizing enterocolitis (NEC). Recent studies have indicated that the gut microbiota imbalance can be restored after a single or multi-strain probiotic supplementation, especially mixtures of Lactobacillus and Bifidobacterium strains. Following the systematic search methodology, the current review addresses the importance of probiotics as a preventive or therapeutic tool for dysbiosis produced during the perinatal and infant period. We also discuss the safety of the use of probiotics in pregnant women, preterm neonates, or infants for the treatment of atopic diseases and infections.

During pregnancy, cycles of hypoxia and oxidative stress play a key role in the proper development of the fetus. Hypoxia during the first weeks is crucial for placental development, while the increase in oxygen due to the influx of maternal blood stimulates endothelial growth and angiogenesis. However, an imbalance in the number of oxidative molecules due to endogenous or exogenous factors can overwhelm defense systems and lead to excessive production of reactive oxygen species (ROS). Many pregnancy complications, generated by systemic inflammation and placental vasoconstriction, such as preeclampsia (PE), fetal growth restriction (FGR) and preterm birth (PTB), are related to this increase of ROS. Antioxidants may be a promising tool in this population. However, clinical evidence on their use, especially those of natural origin, is scarce and controversial. Following PRISMA methodology, the current review addresses the use of natural antioxidants, such as epigallocatechin gallate (EGCG), melatonin and resveratrol (RESV), as well as other classical antioxidants (vitamin C and E) during the prenatal period as treatment of the above-mentioned complications. We review the effect of antioxidant supplementation on breast milk in lactating mothers.

Kohl is a traditional cosmetic widely used in Asia and Africa. In recent years, demand for kohl-based eyelids and lipsticks has increased in Europe, linked to migratory phenomena of populations from these continents. Although the European legislation prohibits the use of heavy metals in cosmetics due to the harmful effects to human health, particularly to pregnant women and children, these elements are still present in certain products. The European Union recommended levels are Pb < 20 ppm, As < 5 ppm, Cd < 5 ppm, Sb < 100 ppm, and Ni < 200 ppm. In Germany, levels are more restrictive: Pb < 2 ppm, As < 0.5 ppm, Cd < 0.1 ppm, Sb < 0.5 ppm, and Ni < 10 ppm. Here, we analyzed 12 kohl-based cosmetics in different presentations (powder, paste, and pencil) that were purchased in Spanish and German local shops. An inductively coupled plasma optical emission spectrophotometer was used to identify toxic elements and heavy metals. Levels of Pb ranged between 1.7 and 410,000 ppm in six of the study samples, four of which had levels above the recommended limit of at least two heavy metals. Arsenic (a carcinogenic element) values were within the range allowed by the EU in only 58% of the studied samples. Moreover, two products doubled this limit, reaching levels of 9.2 and 12.6 ppm. In one of the products, cadmium, related to toxic keratitis, was four times higher (20.7 ppm) than that allowed, while in two other products, these limits were doubled (11.8 and 12.7 ppm). Our results indicate the need to supervise the manufacture of kohl-based traditional products and the analysis of their composition prior distribution in European countries.