Obese children were less hydrated than normal weight ones because, taking into account their z-BMI, they drank less. Future prospective studies are needed to explore possible causal relationships between hydration and obesity.

Context Non-alcoholic fatty liver disease (NAFLD) is associated with insulin resistance (IR) and predicts type 2 diabetes. Currently, it is uncertain whether NAFLD may directly cause IR or vice versa. Objective To test the hypothesis that NAFLD is causally related to IR. Design and methods We performed a Mendelian Randomization (MR) in 904 obese children/adolescents, using a NAFLD-related genetic risk score (GRS) as instrumental variable. We assessed NAFLD by ultrasonography and IR by homeostasis model assessment (HOMA-IR). We also interrogated the MAGIC Consortium dataset of 46,186 adults to assess the association between PNPLA3 rs738409 (i.e., the most robust NAFLD-related polymorphism) and HOMA-IR, and we performed a two-sample MR with two large datasets to test reverse causation (HOMA-IR increasing the risk of NAFLD). Results NAFLD prevalence increased by 20% for every increase in the GRS (β-coefficient=0.20,p&0.001). NAFLD was associated with ln-HOMA-IR (β-coefficient=0.28,p&0.001). Thus, the expected increase in ln-HOMA-IR for every increase in the GRS (expected β-coefficient) was 0.056 (0.28*0.20), in the case of complete NAFLD-HOMA-IR causal association, and 0.042 in the case of 75% causality. In our cohort, the GRS did not predict ln-HOMA-IR (β-coefficient=0.007,p=0.75). In the MAGIC cohort, the PNPLA3 rs738409 did not associate with ln-HOMA-IR. The two-sample MR failed to show a causal association between ln-HOMA-IR and NAFLD. Conclusions Our study shows that genetically-influenced NAFLD does not increase HOMA-IR, and genetically-influenced HOMA-IR does not increase the risk of NAFLD. Shared pathogenic pathways or NAFLD subtypes not “captured” by our MR design might underpin the association between NAFLD and HOMA-IR.

Background and Aims: Skipping breakfast influences cognitive performance. The aim of our study was to investigate the relationship between the variation of hormonal and metabolic postprandial parameters induced by breakfast consumption or fasting and cognitive performance in obese children. Methods: Cross-sectional study for repeated measures. Memory and attention assessment tests, hormones and nutrient oxidation were measured before and after consuming breakfast vs fasting in 10 prepubertal obese children. Results: Fasting induced a significant (Po0.05) increase of the Overall Index of the Continuous Performance Test II (a global index of inattention) and the Test of Memory and Learning Word Selective Reminding (a test of verbal memory), whereas no changes were found after breakfast. Fasting was associated with a reduction of insulin and an increase in glucagon, with no changes in glucose. The increase in inattention was associated with a reduction of carbohydrate oxidation (r ¼ À0.66, Po0.05). We found no difference in the area under the curve of peptide YY and glucagon-like peptide-1 after breakfast or fasting, whereas Ghrelin was significantly lower. No association between postprandial hormone variation and cognitive performance was found. Conclusions: Attention and visual memory performance in the morning were reduced when the children skipped breakfast. No association was found with hormones or metabolic changes, but we did find an association with a reduction of carbohydrate oxidation. Nevertheless, these preliminary findings need confirmation in larger sample size.

The aim of the “Smuovi La Salute” (“Shake Your Health”) project was to implement an integrated and comprehensive model to prevent and treat overweight and obesity in low socioeconomic status (SES) and minority groups living in three different districts in the north of Italy. An app and a cookbook promoting transcultural nutrition and a healthy lifestyle were developed, and no-cost physical activities were organized. Healthy lifestyle teaching was implemented in 30 primary school classrooms. Learning was assessed through pre- and post-intervention questionnaires. At the Obesity Pediatric Clinic, overweight and obese children of migrant background or low SES were trained on transcultural nutrition and invited to participate in the project. Primary school students increased their knowledge about healthy nutrition and the importance of physical activity (p-value < 0.001). At the Obesity Pediatric Clinic, after 6 months, pre–post-intervention variation in their consumption of vegetables and fruit was +14% (p < 0.0001) and no variation in physical activity habits occurred (p = 0.34). In this group, the BMI z-score was not significantly decreased (−0.17 ± 0.63, p= 0.15). This study demonstrates the feasibility and efficacy of telematic tools and targeted community approaches in improving students’ knowledge with regard to healthy lifestyle, particularly in schools in suburbs with a high density of migrants and SES families. Comprehensive and integrated approaches provided to the obese patients remain mostly ineffective.

The Metabolic Syndrome may be tentatively defined as the clustering of several metabolic risk factors in the same individual. A progressively higher number of children and adolescents is affected by this syndrome worldwide, mainly as a consequence of the constant increase of the prevalence of obesity and sedentary habits. As obesity, the chance that the metabolic syndrome traks into adulthood is high. Moreover, the evidence of an association between the duration of the exposition to metabolic risk factors and morbidity and mortality justifies early treatment and prevention of the metabolic syndrome in both children and adolescents. Treatment includes behavioral interventions, adequate nutrition and physical activity, and, if necessary, pharmacological treatments aimed at reducing excessive weight, dyslipidemia, hypertension, and glucose impairments. A multidisciplinary and staged approach to treatment, which includes pediatrician, mental health practitioner, dietician, and nurses, is crucial. Usually, the reduction of fat mass promotes an overall improvement of all the components of the metabolic syndrome. Nevertheless, every single component of the metabolic syndrome should be treated as quickly as possible, by using the best current practice. Drugs may be necessary for treating hypertension, type 2 diabetes mellitus and dyslipidemia. In selected cases of gross obesity resistant to treatment, surgical therapy may be also performed.