Effects of Nighttime Eating Behavior on Cardiometabolic Health and Sleep: A Crossover Study

Abstract

Background and aims: The impact of night-eating behavior (NEB) on metabolic health remains underexplored, particularly in healthy populations. We have hypothesized that NEB adversely affects metabolic parameters, liver function, and sleep via circadian disruption and neurohormonal alterations. Methods and results: In this single-center crossover study, sixteen healthy adults (aged 18-35 years) with no comorbidities, no medication use, and a body mass index between 18 and 30 kg/m(2) participated in two one-week dietary regimens: regular eating (no food after 7:30 p.m.) and nighttime eating (>= 25 % of daily caloric intake consumed after 9:30 p.m.). Clinical, biochemical, neurohormonal, and respiratory polygraphy data were obtained following each dietary period. The mean age of participants was 27 +/- 4 years. After adjusting for multiple comparisons, nighttime eating behavior (NEB) was associated with significant increases in albuminuria (p = 0.003), serum phosphate (p < 0.001), fasting triglycerides (p = 0.039), and C-reactive protein (CRP; p = 0.01). NEB also elevated serum leptin (p = 0.007), ghrelin (p < 0.001), cortisol (p = 0.041), fibroblast growth factor 21 (FGF-21; p < 0.001), and cytokeratin-18 (p < 0.001), while significantly decreasing melatonin levels (p < 0.001). Sleep study results demonstrated significant increases in the apnea-hypopnea index (AHI; p < 0.001), supine AHI (p < 0.005), oxygen desaturation (7 % +/- 2 % vs. 11 % +/- 3 %; p < 0.001). Conclusion: NEB significantly affects neurohormonal profiles and sleep-related respiratory metrics in healthy individuals, indicating potential adverse effects on cardiometabolic health during short-term evaluation in healthy subjects.