Narrative review explores links between antibiotic exposure and obesity or metabolic phenotypes

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Frontiers in Medicine Published April 18, 2026 Medically reviewed April 25, 2026 DOI ↗ By Dr. Amelia Tan, PhD · Internal Medicine & Chronic Disease

Key Takeaway

Consider that this narrative review suggests potential links between antibiotic exposure and metabolic phenotypes but lacks quantitative evidence.

This narrative review explores the relationship between antibiotic exposure and obesity or metabolic phenotypes. The scope includes a discussion of specific antibiotic classes such as macrolides, lincosamides, fluoroquinolones, and beta-lactam antibiotics. The authors synthesize existing literature to highlight potential connections between these exposures and metabolic outcomes.

The review does not report a specific population, sample size, or follow-up duration. Primary outcomes and secondary outcomes were not reported in the source material. Consequently, no pooled effect sizes or specific adverse event rates are provided. The authors acknowledge that without quantitative data, the certainty of any observed associations remains uncertain.

Limitations regarding funding, conflicts of interest, and specific study settings were not reported. The review does not provide data on tolerability, discontinuations, or serious adverse events. Given the narrative nature of the source, clinical recommendations must be made with restraint, recognizing that the evidence is observational and does not establish causality.

Practice relevance is not explicitly detailed in the source. Clinicians should interpret these findings as hypothesis-generating rather than definitive guidance. Further research with rigorous study designs is needed to clarify the role of antibiotic exposure in metabolic health.

Study Details

Study typeSystematic review

EvidenceLevel 1

PublishedApr 2026

View Original Abstract ↓

Antibiotics are among the most commonly used anti-infective agents in modern medicine. However, their long-term effects on the gut microbiome have attracted increasing attention. Epidemiological studies and animal experiments in recent years suggest that antibiotic exposure can disrupt the structure and function of the gut microbiota, thereby affecting host energy metabolism, fat deposition, and immune homeostasis. Such disruptions may contribute to the development of obesity and related metabolic phenotypes. Different classes of antibiotics exert markedly distinct effects on the gut microbiota. Broad-spectrum antibiotics such as macrolides, lincosamides, and fluoroquinolones often induce more pronounced and prolonged microbial alterations, whereas the effects of certain β-lactam antibiotics appear relatively transient. Antibiotic-induced gut dysbiosis can influence host metabolism through multiple mechanisms, including reduced short-chain fatty acid production, disrupted bile acid metabolism, impaired intestinal barrier function, and chronic low-grade inflammation. These alterations may promote fat accumulation, insulin resistance, and disruption of immune homeostasis. Early-life antibiotic exposure occurs during a critical developmental window for gut microbiota maturation and may exert more profound effects on long-term metabolic health. Recent advances in multi-omics technologies have further illuminated the complex interaction network among antibiotics, the microbiome, and host metabolism. Microecological intervention strategies, such as probiotics and synbiotics, show potential for improving metabolic abnormalities associated with antibiotic-induced dysbiosis. However, their efficacy is strain-specific, and the overall effect size remains limited. This review summarizes current research progress on how antibiotic exposure influences obesity and metabolic phenotypes through the gut microbiota, outlines the underlying mechanisms, and discusses potential applications of microbiological intervention strategies. It also provides insights into antibiotic-related metabolic risks and future precision intervention approaches.