Metabolic Effects of Morning 16/8 Fasting

Study Overview
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Brief Summary
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A study to address the effects of early-day fasting on fat tissue mobilization in comparison to a typical isocaloric Mediterranean and a low-carbohydrate breakfast.

Detailed Description
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The study design meets a cross-over pattern with 3 different morning visits of 6 hour duration each. After an informed consent is received from the participant, a crude medical history, physical examination and collection of somatometric data through bio-impendance analysis will take place. An intravenous catheter will be placed in the participants forearm. At zero time point, depending on study visit, participants will either (A) remain fasted (B) start consuming ta pre-prepared zero-carbohydrate 500 kcal test meal (C) start consuming ta pre-prepared 500 kcal test meal with a composition conforming to a standard Mediterannean breakfast. Participants will be given 10 minutes to consume the meal. Blood samples will be drawn and visual analogue scales (VAS) for hunger and satiety will be filled in at the following time points (min): -15, 0, 15, 30, 60, 90, 120, 180, 240, 300, 360.

Official Title
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Short-term Metabolic Effects of Morning Energy Restriction Versus Two Different Early-day Nutrition Strategies

Conditions
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Overweight and Obesity

Intervention / Treatment
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* Other: fasting
* Other: Low carbohydrate
* Other: Mediterranean


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BMI 18-25 kg/m2 Willfulness to participate Exclusion Criteria: Overweight or obesity (BMI>25 kg/m2) Type 1 or 2 diabetes mellitus Uncontrolled thyroid disorders

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Fasting<br>6-hour morning fasting | Other: fasting<br>* 6-hour fasting<br>|
| Experimental: Low carbohydrate<br>Consumption of a zero-carbohydrate breakfast | Other: Low carbohydrate<br>* Consumption of a zero-carbohydrate breakfast<br>|
| Experimental: Mediterranean<br>Consumption of a Mediterranean breakfast | Other: Mediterranean<br>* Consumption of a Mediterranean-type breakfast<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mobilisation of adipose tissue | Area Under the Curve (AUC) of free fatty acid (FFA) and beta-Hydroxybutyrate (bOB) concentration | 6 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mobilisation of gut peptides | AUC of Ghrelin, Peptide YY and glucagon-like peptide -1 (GLP-1) concentration | 6 hours | 
| Degree of appetite suppression | Visual Analogue Scale score (0-10, 0 equals minimal and 10 equals highest) for appetite | 6 hours | 
| Degree of satiety induction | Visual Analogue Scale score (0-10, 0 equals minimal and 10 equals highest) for satiety | 6 hours |