Background As the prevalence of obesity keeps rising world-wide, new approaches to decrease risk of metabolic disease have been studied, since traditional methods of calorie restriction and physical activity might be insufficient against the vast variety of dietary and lifestyle factors affecting metabolic status. Timing of meals has shown to influence multiple metabolic parameters and has therefore gained popularity among researches as a new strategy for managing bodyweight and improving health status.

Objectives The aim of this study was to test the association between the of the timing of the three main meals and blood lipid profile parameters in a sample of United States adults.

Methods Cross sectional study of the NHANES (2017–2018) survey. Time of intake categories were created for the three main meals (breakfast, lunch, dinner) according quartiles from population values. Multivariable linear regression was performed to test the association between meal timing categories and lipid profile parameters (Total cholesterol, low-density lipoprotein (LDL), triglycerides and high-density lipoprotein (HDL), controlling for potential confounders

Results A final sample of n=3700 adults were included in the analysis. Energy intake increased across meals during the day possibly due to less satiating effect, but also within meals as time of intake was delayed. Those who sleep less had both earlier breakfast and later dinner times (p>0.00), higher WC (p>0.00) but not BMI. Delaying breakfast and lunch was associated with both a higher BMI (p<0.00) and WC (p>0.00), however dinner was only associated with higher WC (p<0.01). Regression models showed an increase in LDL and triglycerides when meals where delayed while HDL remained unaffected. The increase in triglycerides (23.5, 95%CI (9.21, 37.8)) and was more pronounced during breakfast than in any other meal (p>0.00).

Conclusion This study suggests that maintaining earlier periods of intake has a favorable effect on lipid profile parameters such as HDL and triglycerides, as well as other metabolic indicators like BMI and WC. However further research is needed to further study possible long-term effects on HDL and total cholesterol, as well as the most appropriate intake periods for optimal metabolic function.