O045 - A TIME-RESTRICTED EATING PROTOCOL IMPROVES AMBULATORY GLYCEMIC CONTROL IN HEALTHCARE SHIFT WORKERS WITH OVERWEIGHT: A RANDOMIZED CROSSOVER CLINICAL TRIAL

O045

A TIME-RESTRICTED EATING PROTOCOL IMPROVES AMBULATORY GLYCEMIC CONTROL IN HEALTHCARE SHIFT WORKERS WITH OVERWEIGHT: A RANDOMIZED CROSSOVER CLINICAL TRIAL

A. Beaumont¹, D. González¹, R. Peralta², R. Villegas³, P. Rojas¹, R. Chamorro^1,*

¹Department of Nutrition, University of Chile, Santiago, Chile, ²Directorate of Nutrition and Food Programs, National Institute of Food and Nutrition, Asunción, Paraguay, ³Biostatistics Program, School of Public Health, University of Chile, Santiago, Chile

Rationale: Night shift work disrupts circadian rhythms and metabolic regulation, increasing cardiometabolic risk. Time-restricted eating (TRE) may improve glycemic control. We evaluated the effect of TRE on ambulatory glycemic regulation in healthcare workers performing rotating shifts.

Methods: A randomized crossover trial was conducted in 22 healthcare workers (37.2 ± 9.5 years; BMI: 29.4 ± 5.1 kg/m²) in Santiago, Chile. Participants completed two 8-week conditions, separated by a ≥30-day washout: (i) TRE (≤10 h/day self-selected eating window, with mandatory fasting between 00:00–06:00 h) and (ii) regular eating (REG). Interstitial glucose was measured using continuous glucose monitoring (FreeStyle Libre2) over 10 consecutive days before and after each condition. 24-h data were analyzed in 4-hour intervals using linear mixed-effects models adjusted for age, BMI, sleep, and activity. Significance was set at 5%.

Results: TRE reduced mean 24-hour glucose (β = −2.02 mg/dL; 95% CI: −2.60 to −1.44; p<0.001) versus REG, with greater effects during 00:00–04:00 h (β = −5.26 mg/dL; 95% CI: −6.68 to −3.84), 04:00–08:00 h (β = −3.44 mg/dL; 95% CI: −4.39 to −2.49), and 08:00–12:00 h (β = −3.90 mg/dL; 95% CI: −5.10 to −2.71; all p<0.001), and no differences in other time intervals (all p>0.110). TRE also reduced intraday variability (CONGA-1; β = −5.57 mg/dL; 95% CI: −5.64 to −5.49; p<0.001) and improved interday stability (MODD; β = 1.46 mg/dL; 95% CI: 1.30 to 1.53, p<0.001). Time in range increased significantly (β = 0.52%; 95% CI: 0.43 to 0.60; p<0.001).

Conclusion: TRE is useful to improve glycemic control across the 24-h, particularly overnight and in the morning, supporting its use as a simple dietary strategy to enhance metabolic health in this group of rotating shift workers. [Funding: Fondecyt, ANID Chile #12230075 to RC]

Disclosure of Interest: None declared