Skipping breakfast and its wide-ranging health consequences: A systematic review from multiple metabolic disruptions to socioeconomic factors

Skipping breakfast has been widely debated due to its potential health consequences across multiple domains. This systematic review evaluates literature from 2010 to 2025, analyzing 66 studies to assess its associations with obesity, diabetes, gut microbiome alterations, neurodegenerative diseases, cancer, sports performance, psychiatric disorders, cognitive health, and socioeconomic factors. The hypothesis suggests that breakfast omission is linked to various adverse health effects. Evidence highlights associations with obesity and weight gain due to altered hormonal responses influencing hunger and energy balance. Additionally, skipping breakfast negatively affects gut microbiota, contributing to systemic inflammation and metabolic dysfunction. Research suggests potential links to increased cancer risk through inflammatory pathways, while cognitive decline, mood disorders, and impaired athletic performance are also observed. Psychiatric disorders, including anxiety and depression, may be exacerbated by irregular meal patterns, influencing neurotransmitter regulation. Emerging studies indicate that breakfast consumption plays a role in bone mineral density, as prolonged fasting periods may affect calcium metabolism and skeletal health. Socioeconomic disparities impact breakfast consumption, affecting diet quality and overall health outcomes. While some individuals experience neutral or even beneficial effects, meal timing and caloric distribution play critical roles in metabolic and cardiovascular health. However, causality remains complex due to confounding factors like diet quality, physical activity, and socioeconomic status. Current studies face limitations, including small sample sizes and short intervention periods, requiring further research to refine conclusions and explore long-term mechanisms behind breakfast omission’s health impacts.