Time-restricted Feeding and Health

NCT07505680 | Completed

• 1 other identifier: Γ-1936/02-05-2025
• Study Type: interventional
• Target: 16
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this pilot, single-arm clinical trial is to assess the effects of time-restricted feeding on overall health, including body composition, glycemic and lipidemic profile, as well as appetite-regulating hormones, including glucagon-like peptides 1(GLP-1) oxyntomodulin, glucagon. Additionally, the study aims to evaluate the impact of this dietary pattern on circadian rhythm parameters, including acrophase, mesor, and amplitude.

Conditions

Appetite; Circadian Rhythm; Metabolic Health; Body Weight Control; Glycemic and Insulinemic Response

Outcome Measures

Primary Outcomes (1)

• Changes from baseline in appetite-regulating hormones , including GLP-1 in pg/mL, oxyntomodulin in pg/mL, and glucagon in pg/mL at week 4, measured by ELISA kits.

  Participants arrived at the laboratory between 08:30 and 09:00. An antecubital catheter was placed, and five blood samples were collected at fasting (0 min) and at 30, 60, 90, and 120 minutes after consuming the test meal. The test meal consisted of 100 g of S-Core FLEX Compact Protein powder (40 g carbohydrate, 29 g protein, 19 g fat) dissolved in 250 mL of water, providing 475 kcal.

  Baseline and Week 4

Secondary Outcomes (3)

• Changes from baseline in circadian rhythm parameters (acrophase in degrees of Celcious, mesor in time units, amplitude in degrees of Celcious) at week 4, measured through continouous measurements in skin termperature by a thermistor.

  Baseline and Week 4

• Changes from baseline in Body Composition, namely fat free mass in kg and fat mass in kg

  Baseline and week 4

• Changes from Baseline in Glycemic and Lipidemic Profile, assessed by photometry.

  Baseline and Week 4

Study Arms (1)

Time-Restricted Feeding

OTHER

Participants followed a four-week regimen of ad libitum food intake from 08:00 to 18:00, followed by a 14-hour fasting period until 08:00 the next day, while maintaining habitual physical activity and sleep patterns.

Other: Time-Restricted Feeding

Interventions

Time-Restricted Feeding OTHER

Ad libitum food intake from 08:00 to 18:00, followed by fasting from 18:00 to 08:00 for four weeks. Outside the eating window, water and limited amounts (1-2 servings) of very low-calorie items (e.g., tea, diet soft drinks, coffee, chewing gum \<4 kcal/serving) were permitted. The intervention focused exclusively on the timing of food intake and did not impose restrictions on the quantity or type of foods consumed.

Time-Restricted Feeding

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy men or women aged 18-35 years
• Habitual daily eating window \>10 hours
• Stable body weight over the past 3 months (\< ±10% change)
• Able to provide informed consent independently

You may not qualify if:

• Night shift work more than once per week
• Presence of chronic diseases (e.g., cancer, renal or hepatic disease, inflammatory bowel disease, hypertension, diabetes, cognitive or psychiatric disorders)
• Eating disorders
• Use of medications affecting the intervention (e.g., corticosteroids, antidiabetics)
• Pregnancy or planning pregnancy within the next 12 months
• Diagnosis of insomnia

Sponsors & Collaborators

• Harokopio University: lead

Study Sites (1)

Harokopio University of Athens

Athens, Attica, 17676, Greece

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: January 15, 2026
• First Posted: April 1, 2026
• Study Start: June 4, 2025
• Primary Completion: December 16, 2025
• Study Completion: December 16, 2025
• Last Updated: April 1, 2026

Record last verified: 2026-03

Locations

GR (1)