Diet, Metabolic Dysregulation and Asthma Control in Children: Integrating the Gut–Lung Axis into Clinical Practice

Pediatric asthma is a heterogeneous disease characterized by complex interactions among airway inflammation, nutritional status, metabolic health, environmental exposures, and immune regulation. This narrative review summarizes current evidence linking dietary patterns, adiposity, metabolic dysfunction, systemic inflammation, and microbiome-related mechanisms with pediatric asthma outcomes while distinguishing evidence on asthma development from that concerning control of the established disease. Healthier dietary patterns have generally been associated with lower asthma or wheezing prevalence, but pediatric dietary intervention trials in established asthma remain few and have produced heterogeneous results across asthma control, exacerbations, lung function, inflammatory markers, and medication use. Obesity and metabolic dysfunction are more directly associated with morbidity and treatment response in children with established asthma. The gut–lung axis provides a biologically plausible framework connecting diet, microbial metabolites, epithelial barrier function, and immune regulation. However, early-life microbiome findings primarily inform asthma susceptibility and immune development rather than disease control. Therefore, current care should remain focused on guideline-based asthma management, complemented by an appropriate assessment of diet, obesity, physical activity, and metabolic health. Further pediatric intervention studies are needed to determine whether targeted nutritional, metabolic, or microbiome-based strategies can reproducibly improve asthma control.