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

Abstract

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 ± 3.1cm (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.

Time-Restricted Eating as a Nutrition Strategy for Individuals with Type 2 Diabetes: A Feasibility Study

“…Total energy intake, macronutrient distribution and the number of eating occasions did not change over the four-week TRE period. Further, participants reported being adherent on 43% of days deemed non-adherent by recorded timing, suggesting previous studies using self-reporting methodology may have overestimated adherence [2,5].…”

“…While various measures of glycaemic control have been improved in previous ad libitum and energy-matched TRE interventions of varying durations (4 days to 12 weeks), all previous investigations have been in those with normal or impaired glucose tolerance [4,5,[7][8][9]27,44,48]. Individuals with T2D have altered circadian patterns of glucose regulation [17,49], with greatest impairments to glucose tolerance in the morning compared to the evening in those with normal or impaired glucose tolerance.…”

“…Time-restricted eating (TRE) is a dietary strategy in which food intake is reduced to a "window" of 8-12 h/day during waking hours. TRE has been demonstrated to be a simple and practical behavioural intervention that can reduce energy intake in those with obesity or metabolic syndrome [1][2][3][4][5], although TRE may be more difficult in older (>65 years) populations [6]. Controlled studies of isoenergetic TRE have shown beneficial effects on glucose tolerance, insulin sensitivity, and 24-h glucose profiles in individuals at risk of developing type 2 diabetes mellitus (T2D) [7][8][9] as well as reductions in appetite in persons with overweight/obesity [10].…”

Beneficial Effects of Time-Restricted Eating on Metabolic Diseases: A Systemic Review and Meta-Analysis

“…Two of three non-randomized controlled trials had the moderate risks of bias [37,39] and one had the serious risk [44]. Five trials with a one group pretest-posttest design had a serious risk of bias [23,29,32,34,42].…”

“…Upon further review and quality assessment, we found 21 studies that met the topic of interest. Among the 21 studies [23,[26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45], two were excluded for meta-analysis [26,27]. Their main results have been summarized in Supplementary Materials Table S3.…”