Eating jetlag and risk of cardiovascular disease: prospective study of the NutriNet-Santé cohort

Abstract Background Social jetlag corresponds to the misalignment between biological circadian rhythms and the social rhythm imposed by society, resulting in discrepant activity/sleep schedules during work and free days. It has been associated with worsened biological parameters such as BMI or glycemic control. Eating jetlag is a related yet emerging concept defined as the difference of meal timing between free and work days. However, it has been little explored. This study aims to evaluate the association between eating jetlag and the risk of cardiovascular disease (CVD). Methods Dietary, anthropometric, socio-demographic and health data of 104,837 participants (79% women, mean age=42.7 years (14.6 SD)) were collected from the NutriNet-Santé cohort. Eating jetlag was calculated using time of first and last meals on weekdays and weekends, from repeated 24 dietary records, averaged during the 2 first years. It was assessed as a continuous variable or as 3 categories: ‘Advance’, ‘Maintenance’, ‘Delay’, compared to work days. CVD was self-reported and validated against medical records. The associations between eating jetlag and CVD risk were assessed through adjusted Cox models. Results During a median follow-up time of 8.1 years, 2,368 CVD cases were diagnosed. Eating jetlag showed a U-shaped association with CVD risk (HR Advance vs. Maintenance=1.05(95% CI: 0.87-1.26); HR Delay vs. Maintenance=1.08(0.96-1.21)). When the absolute value of eating jetlag was considered, there was a linear association with CVD risk (HR per 1-hour increase=1.05(1.00-1.12)). These linear trends were confirmed in categorial models (Low: ≤1h; Moderate: 1h< to ≤ 2h; High: >2h): HR Moderate vs. Low=1.05(0.94-1.18), and HR High vs. Low=1.13(0.94-1.37); however, statistical significance was not reached. Conclusions Our results suggest a potential role for meal timing regularity between free and work days in CVD etiology. They need to be replicated in other studies and mechanisms are yet to be fully understood. Key messages • Adopting regular meal timing schemes on work and free days could be associated with a lower risk of cardiovascular diseases. • Meal regularity between work and free days could play a role in cardiovascular health and should be further investigated.