Chrononutrition, body composition and handgrip strength in a large French cohort

Background/Objectives

Meal timing has emerged as a potential modifiable determinant of weight change and metabolic health. However, the relationship between meal timing with body composition and handgrip strength (HGS) as a functional proxy of muscle quality remains unclear. This cross-sectional study estimated these associations in a French cohort.

Methods

NutriNet-Santé is a French web-based cohort launched in 2009. Participants completed bi-annual 24-hour dietary records and underwent a body composition assessment and a HGS test. We conducted multivariable regression analyses to examine the relationship between meal timing and frequency, anthropometrics (BMI, waist circumference (WC)), body composition measures (fat mass index (FMI) to lean mass index (LMI) ratio, percentage body fat (%BF)), and HGS. Models were adjusted for common sociodemographic and lifestyle confounders, including diet quality. The false discovery rate (FDR)-adjusted p-values were applied.

Results

The analysis included 13,941 participants (72% females, age 53.8 ± 13.6). In females, a later first eating occasion was associated with BMI (ß=0.005, p = 0.006), %BF (ß=0.393, p < 0.0001), and FMI/LMI ratio (ß=0.008, p < 0.0001), and inversely associated with HGS (ß=-0.128, p < 0.0001). Time of last eating occasion was not associated with any of the outcomes. Caloric midpoint and eating jetlag were positively associated with BMI, WC, %BF, FMI/LMI ratio, with stronger and more consistently observed associations in males. For example, a later caloric midpoint was associated with higher WC (ß= 0.222, p = 0.03), %BF (ß=0.178, p =0.001), FMI/LMI ratio (ß=0.003, p = 0.001) in males but not females. The number of eating occasions was negatively associated with BMI (ß=-0.075, p < 0.0001), WC (ß=-0.224, p < 0.0001), FMI/LMI ratio (ß=-0.004, p < 0.0001) and %BF (ß=-0.194, p < 0.0001), in both males and females.

Conclusions

Later and irregular meal timing could be associated with a higher adiposity and a worse muscle function.

Key messages

• Earlier food intake and calorie distribution, and a consistent meal timing between weekdays and weekends could have potential benefits for adiposity and functional health, with sex-specific effects.

• Longitudinal and long-term interventional studies are necessary to establish their causal role in obesity and to develop evidence-based recommendations.