Early time-restricted eating affects weight, metabolic health, mood, and sleep in adherent completers: A secondary analysis

Abstract

Objective: Data are mixed on whether intermittent fasting improves weight loss and cardiometabolic health. Here, the effects of time-restricted eating (TRE) in participants who consistently adhered ≥5 d/wk every week were analyzed.

Methods: Ninety patients aged 25 to 75 years old with obesity were randomized to early TRE (eTRE; 8-hour eating window from 07:00 to 15:00) or a control schedule (≥12-hour window) for 14 weeks. A per-protocol analysis of weight loss, body composition, cardiometabolic health, and other end points was performed.

Results: Participants who adhered to eTRE ≥5 d/wk every week had greater improvements in body weight (-3.7 ± 1.2 kg; p = 0.003), body fat (-2.8 ± 1.3 kg; p = 0.04), heart rate (-7 ± 3 beats/min; p = 0.02), insulin resistance (-2.80 ± 1.36; p = 0.047), and glucose (-9 ± 5 mg/dL; p = 0.047) relative to adherers in the control group. They also experienced greater improvements in mood, including fatigue and anger; however, they self-reported sleeping less and taking longer to fall asleep.

Conclusions: For those who can consistently adhere at least 5 d/wk, eTRE is a valuable approach for improving body weight, body fat, cardiometabolic health, and mood. Further research is needed to determine whether eTRE's effects of shortening sleep but reducing fatigue are healthful or not.

Figure 1.. Eating Window.

(A) Adherent completers in the early time-restricted eating plus energy restriction (eTRE+ER) group fasted for an additional 5.2 hours per day relative to those in the control eating schedule plus energy restriction (CON+ER) group. (B) Adherent completers in both groups started eating about the same time of day, but those in the CON+ER group finished eating at 20:45 ± 1:06, whereas those in the eTRE+ER group stopped eating at 15:18 ± 0:18. * p<0.05

Figure 2.. Weight and Body Composition.

Among adherent completers, early time-restricted eating plus energy restriction (eTRE+ER) was more effective for losing (A) weight, (B) body fat, and (D) trunk fat than the control eating schedule plus energy restriction (CON+ER). There were no differences in (C) fat-free mass, (E) visceral fat (n=30), (F) waist circumference, and (G) appendicular lean mass between groups. * p<0.05

Figure 3.. Cardiometabolic Risk Factors.

Among adherent completers, early time-restricted eating plus energy restriction (eTRE+ER) was more effective at decreasing (A) fasting glucose, (C) insulin resistance as measured by HOMA-IR, and (H) heart rate (n=35) than the control eating schedule plus energy restriction (CON+ER). There were no differences in (B) fasting insulin, (D) HOMA-β, (E) HbA1c, (F) systolic blood pressure, (G) diastolic blood pressure, (I) total cholesterol, (J) triglycerides, (K) LDL cholesterol, and (L) HDL cholesterol between groups. * p<0.05

Figure 4.. Mood.

Among adherent completers, early time-restricted eating plus energy restriction (eTRE+ER) was more effective at improving (A) the total mood disturbance score and subscores for (B) vigor-activity, (C) fatigue-inertia, (D) depression-dejection, and (E) anger-hostility than the control eating schedule plus energy restriction (CON+ER). There were no differences between groups in (F) tension-anxiety, (G) confusion-bewilderment, or (H) the severity of clinical depression as measured by the Patient Health Questionnaire-9 (PHQ-9) score. * p<0.05

Figure 5.. Sleep.

Among adherent completers, early time-restricted eating plus energy restriction (eTRE+ER) decreased (A) sleep duration and (G) sleep efficiency and increased (F) sleep latency relative to the control eating schedule plus energy restriction (CON+ER). There were no differences in (B) sleep onset, (C) sleep offset, (D) chronotype, (E) sleep quality, and (H) sleep inertia between groups. * p<0.05