Background: Time-restricted eating (TRE) is increasingly popular for weight loss, yet its effects on glycemic measures remain unclear. Using continuous glucose monitor (CGM) worn for 2 weeks at baseline and end-intervention, we hypothesized that TRE may reduce glycemic variability compared to unrestricted eating (non-TRE) in patients who are overweight and without diabetes.

Method: Participants (17 women and 3 men; mean [SD] age: 45.5 [12.1] years; BMI 34.1 [7.5] kg/m2) without self-reported diabetes (HbA1c 5.5 [0.4]) who had prolonged eating window (15.4 [0.9] hours) were randomized to a 12 week intervention of either TRE (n=11: 8-hour window, unrestricted eating within window) versus non-TRE (n=9: unrestricted eating) . Each participant wore a blinded CGM (Freestyle Libre Pro) for 2 weeks prior to randomization and at end-intervention (week 11-12) . At each time point, multiple measures of glycemic variability were calculated from the raw CGM data. This is a secondary analysis of a previously published study where 12 weeks of TRE did not alter HbA1c.

Result: Between the TRE and non-TRE groups in the pre and end-intervention periods, there was no statistical difference in any of the calculated glycemic variability measures: including, time in range (TIR) , standard deviation (SD) , coefficient of variation (CV) , continuous overlapping net glycemic action (CONGA) , liability, Index, J-index, low and high blood glucose index (LBGI/HBGI) , glycemic risk assessment diabetes equation (GRADE) , mean of daily differences (MODD) , average daily risk range (ADRR) , mean amplitude of glycemic excursions (MAGE) , mean of daily differences (MODD) , Area Under Curve (AUC) , and Glucose Management Indicator (GMI) .

Conclusion: In patients who are overweight without diabetes, TRE did not alter CGM-measured glycemic variability. Further studies regarding TRE effects on glycemic variability should focus on participants with diabetes.


A.Mehfooz: None. Y.Lee: None. Q.Wang: None. L.S.Chow: Other Relationship; Dexcom, Inc.

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