Appetite, Circadian Rhythm, Metabolic Health, Body Weight Control, Glycemic and Insulinemic Response
Conditions
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.
Interventions
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.
Sponsors
Harokopio University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
Yes
Inclusion criteria
* 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
Exclusion criteria
* 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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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. | Baseline and Week 4 | 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. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| 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 | Participants wore a wireless skin temperature sensor (Thermochron iButton® DS1921-F5) on the palmar surface of the wrist of the non-dominant hand for 2 consecutive days. Circadian rhythmicity was analyzed using Cosinor analysis, which applies the least-squares method to fit the chronobiological data to cosine functions with predetermined periods of 12 and 24 hours. |
| Changes from baseline in Body Composition, namely fat free mass in kg and fat mass in kg | Baseline and week 4 | Participant's body composition measurement pre/post time restricted feeding protocol |
| Changes from Baseline in Glycemic and Lipidemic Profile, assessed by photometry. | Baseline and Week 4 | Biochemical measurements in blood. |
Countries
Greece
Outcome results
None listed