Prolonged eating into late evening hours is associated with overweight (OW)/obesity (OB) and increases metabolic risk. Reducing the daily eating window, or time restricted eating (TRE), results in weight loss (WL) and improved metabolism. Our goal was to assess: 1) The eating patterns of adults with OW or OB and 2) The effect of 10h/d TRE, in persons who habitually eat for ≥14h/d, on WL and systolic (SBP) and diastolic (DBP) blood pressure.

Methods: In this open label study, eligible men and women with BMI ≥25kg/m2 were instructed to enter all caloric eating occasions (EO) via time-stamped photos using the validated MyCircadianClock smartphone application (app) for 2 weeks (run-in). No instructions were provided on food choice or calorie count. Upon completion of this run-in period, eligible participants entered a 3-mo personalized 10h/d TRE intervention administered remotely via the app. Adherence was defined as logging 2 or more EO/d, occurring at least 5h apart, and achieving a 4h reduction in eating window during TRE.

Results: Participants in the run-in period (n=30, 20% men) were 51.9±11.9y old, had a BMI of 31.1±7.3 kg/m2, waist circumference of 100.1±13.2 cm, SBP of 117.3±15.0 mmHg and DPB of 76.0± 10.5 mmHg. Logging into the app occurred on 10.9±3.2 days with a total of 61±30 [10-121] EO. The duration of the daily eating window varied greatly amongst participants (range: 8h02min - 23h26min) and ∼50% of them ate ≥14h/d. During the 3-mo TRE (n=12), login adherence was observed on 63% of days, with a mean of 3.4±1.7 EO/d; the mean eating duration decreased by 5.79±2.74 h/d (p=0.001). Weight decreased by 3.0± 2.7 kg (p=0.025). SBP and DBP also decreased by 21±11 mmHg (p=0.013) and 13±20 mm Hg (p=0.04), respectively.

Conclusion: TRE administered via a smartphone app is an effective and easy-to-implement intervention to reduce body weight and blood pressure in adults with OW and OB. These data need to be confirmed in randomized trials.


M.A. Prasad: None. E. Manoogian: Stock/Shareholder; Spouse/Partner; Abbott Laboratories. F.M. Zuraikat: None. N. Nair: None. M. St-Onge: None. S. Panda: Other Relationship; Self; Penguin Random House.

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