A pilot feasibility study exploring the effects of a moderate time-restricted feeding intervention on energy intake, adiposity and metabolic physiology in free-living human subjects

Abstract

This pilot study explored the feasibility of a moderate time-restricted feeding (TRF) intervention and its effects on adiposity and metabolism. For 10 weeks, a free-living TRF group delayed breakfast and advanced dinner by 1·5 h each. Changes in dietary intake, adiposity and fasting biochemistry (glucose, insulin, lipids) were compared with controls who maintained habitual feeding patterns. Thirteen participants (29 (sem 2) kg/m2) completed the study. The average daily feeding interval was successfully reduced in the TRF group (743 (sem 32) to 517 (sem 22) min/d; P < 0·001; n 7), although questionnaire responses indicated that social eating/drinking opportunities were negatively impacted. TRF participants reduced total daily energy intake (P = 0·019) despite ad libitum food access, with accompanying reductions in adiposity (P = 0·047). There were significant between-group differences in fasting glucose (P = 0·008), albeit driven primarily by an increase among controls. Larger studies can now be designed/powered, based on these novel preliminary qualitative and quantitative data, to ascertain and maximise the long-term sustainability of TRF.

Time‐Restricted Eating Effects on Body Composition and Metabolic Measures in Humans who are Overweight: A Feasibility Study

“…Human TRE studies providing all food to maintain isoenergetic intake have reported weight stability with variable effects on glycemic measures (4‐6). Human studies on TRE with ad libitum intake have reported modest weight loss (approximately 3%, 3 kg) (3,7‐9), although glycemic measures remained unchanged (7‐9).…”

A Delayed Morning and Earlier Evening Time-Restricted Feeding Protocol for Improving Glycemic Control and Dietary Adherence in Men with Overweight/Obesity: A Randomized Controlled Trial

“…Recently, dietary strategies that focus on the timing of eating and duration of fasting (i.e., chrono-nutrition), rather than the type, quality or quantity of foods, have been demonstrated to improve metabolic health independent of weight loss [12,13]. Specifically, time-restricted feeding (TRF, in which daily food intake is restricted to between 8-10 h) is a dietary strategy that has emerged as a practical intervention for weight loss, and improving insulin resistance along with other markers of whole-body health [10,[12][13][14][15][16]. Controlled (i.e., meals provided) 'early' TRF (eTRF; 0800-1500 h) improved both beta cell function in men with prediabetes [13] and 24-h glucose area under the curve (AUC) in individuals with obesity [12].…”

Meal Frequency and Time - Restricted Feeding as Strategies for Reducing Metabolic Risk : a Review

“…In a pilot study by Antoni et al, 2018, 16 hours fasting for the duration of 10 weeks, was able to produce a significant reduction in % body fat with no change in body weight in 13 overweight participants. This suggests a compensatory increase in lean tissue mass during the intervention 43 .…”

“…Although TRF was or wasn't able to achieve weight loss, the studies have reported a reduction in adiposity 43 and improvement in insulin sensitivity 40 with the increased fasting window (16-18 hours of fasting). In a pilot study by Antoni et al, 2018, 16 hours fasting for the duration of 10 weeks, was able to produce a significant reduction in % body fat with no change in body weight in 13 overweight participants.…”