Adherence to Time-Restricted Feeding and Impact on Abdominal Obesity in Primary Care Patients: Results of a Pilot Study in a Pre-Post Design

The epidemic of lifestyle-dependent diseases and the failure of previous interventions to combat the main causes demand an alternative approach. Abdominal obesity is associated with most of these diseases and is a good target for therapeutic and preventive measures. Time-restricted feeding (TRF) offers a low-threshold, easy-to-implement lifestyle-modification concept with promising results from animal testing. Here, we describe a pilot study of TRF with abdominally obese participants (waist-to-height ratio, WHtR >= 0.5) in a general practitioner's office. Participants (n = 40, aged 49.1 +/- 12.4, 31 females) were asked to restrict their daily eating time to 8-9 hours in order to prolong their overnight fasting period to 15-16 hours. Questionnaires, anthropometrics, and blood samples were used at baseline and at follow-up. After three months of TRF, participants had reached the fasting target, on average, on 85.5 +/- 15.2% of all days recorded. Waist circumference (WC) was reduced by -5.3 +/- 3.1 cm (p < 0.001), and three participants reached a WHtR <0.5. HbA1c was diminished by -1.4 +/- 3.5 mmol/mol (p = 0.003). TRF may be an easily understandable and readily adoptable lifestyle change with the potential to reduce abdominal obesity and lower the risk for cardiometabolic diseases. Further well-designed studies are necessary to investigate the applicability and usefulness of TRF for public health.