Author(s): Lages, Marlene ; Correia, Joana ; Caseiro, Armando ; Carmo-Silva, Sara ; Barros, Renata ; Ferreira-Marques, Marisa ; Guarino, Maria P.
Date: 2025
Persistent ID: http://hdl.handle.net/10400.26/60229
Origin: Instituto Politécnico de Coimbra
Subject(s): chrononutrition; circadian rhythms; diet; obesity; clock genes
Background: The circadian system regulates several physiological processes, including energy metabolism, through the expression of core clock genes. Animal studies suggest that dietary composition can influence circadian gene expression; however, evidence in humans remains limited. Objective: This study aimed to explore the association between dietary macronutrient intake and the expression of circadian clock genes in the whole blood of adults with distinct metabolic profiles. Methods: Nineteen adults (94.7% female; 43.4 ± 16.05 years) were categorized into healthy-weight and overweight/obesity groups based on BMI. Dietary intake was assessed using a 3-day food diary, and clock gene expression (CLOCK, BMAL1, PER2, CRY) was evaluated in whole blood samples collected between 08:00 a.m. and 04:00 p.m. Statistical analyses included group comparisons and correlation analyses between macronutrient intake and gene expression. Results: No statistically significant differences were observed in the clock gene expression between BMI groups, although group-level trends were noted, particularly in PER2 and CRY expression. The overweight/obesity group exhibited a significantly higher percentage of energy intake from protein. Correlation analyses revealed several time-dependent associations between macronutrient intake and clock gene expression. Notably, in the healthy BMI group, BMAL1 and CRY expression correlated with lipid and protein intake, while in the overweight/obesity group, CLOCK expression was strongly associated with both lipid and carbohydrate intake. Conclusion: These findings suggest that macronutrient composition may influence peripheral circadian gene expression in a time- and BMI-dependent manner. Further research is necessary to confirm these associations in larger and more diverse populations and to investigate the potential for chrononutrition strategies to support metabolic health
