Circadian Rhythm and Lipid Metabolism: The Role of the Gut Microbiota

Circadian rhythms play a vital role in lipid metabolism by coordinating lipogenesis, lipolysis and fatty acid oxidation to maintain energy homeostasis. Their regulation is affected by light exposure, feeding time, dietary composition, hormonal signals and gut microbiota. Accordingly, persistent circadian misalignment may therefore increase susceptibility to obesity and related metabolic disorders. Increasing evidence also indicates that the gut microbiota exhibits marked diurnal variation and can, in turn, modulate host metabolic rhythms through microbial metabolites and host–microbe signaling. This review summarizes the major factors influencing circadian rhythms, discusses their regulatory effects on lipid metabolism and the contribution of the gut microbiota, and outlines the relationship between circadian disruption and obesity, with the aim of providing insights into the prevention and intervention of metabolic diseases.