Endogenous vs. Exogenous Ketone Bodies

Not Applicable

Completed

• Conditions: Healthy
• Interventions: Dietary Supplement: Beta-Hydroxybutyrate as Ca-Mg-salt, active; Dietary Supplement: fasting, active; Dietary Supplement: fasting, inactive

• Registration Number: NCT04490226
• Lead Sponsor: University of Kiel

Brief Summary

Aim of the study is to compare the origin of ketone bodies: endogenous ketone bodies due to 36 hours fasting or 24 hours of ketogenic diet vs. exogenous ketone bodies as supplements additional to normal diet.

Secondary aim of the study is to validate the new metabolic chambers.

Detailed Description

Each study week starts with a 3-day run-in period with controlled diet at home and ends with a test-meal (breakfast) in the lab and following food record over the rest of the day at home.

1. week: physical activity level (PAL) 1.3, 3 intervention days in the metabolic chamber: ad libitum energy intake, washout day, isocaloric diet, 36 hours fasting

2. week: physical activity level (PAL) 1.3, 2 intervention days in the metabolic chamber: isocaloric diet, 36 hours fasting

3. week: physical activity level (PAL) 1.6, 2 intervention days in the metabolic chamber: ad libitum energy intake, 36 hours fasting

4. week: physical activity level (PAL) 1.6, 2 intervention days in the metabolic chamber: isocaloric diet, ketogenic diet (isocaloric)

5. week: physical activity level (PAL) 1.6, 2 intervention days in the metabolic chamber: isocaloric diet, isocaloric diet + ketone body supplements (isocaloric)

Study Timeline

• Study First Submitted: 2020-07-16
• Study First Submitted QC: 2020-07-23
• Study First Posted: 2020-07-29
• Study Start: 2020-08-21
• Primary Completion: 2021-07-23
• Study Completion: 2021-07-23
• Status Verified: 2021-09
• Last Update Submitted: 2021-09-30
• Last Update Posted: 2021-10-01

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 8

Inclusion Criteria

• healthy
• BMI 19-29 kg/m2
• low-medium habitual physical activity
• women using hormonal contraceptive

Exclusion Criteria

• smoking
• chronic illnesses
• food allergies / intolerances
• vegans and vegetarians
• regular high physical activity (exercise >1 hour/d)
• current weight loss diet / weight loss of >5 kg in the last 3 months
• pregnant / lactating women
• persons incapable of giving informed legal consent

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
fasting, active	fasting, active	36 hours fasting, PAL 1.6
ketogenic diet, active	fasting, active	24 hours of ketogenic diet (liquid meals), PAL 1.6
ketogenic diet, active	Beta-Hydroxybutyrate as Ca-Mg-salt, active	24 hours of ketogenic diet (liquid meals), PAL 1.6
ketogenic diet, active	fasting, inactive	24 hours of ketogenic diet (liquid meals), PAL 1.6
exogeneous ketone bodies, active	Beta-Hydroxybutyrate as Ca-Mg-salt, active	24 hours of ketone body supplements (Beta-Hydroxybutyrate as Ca-Mg-salt) additional to a normal diet (liquid meals), PAL 1.6
fasting, active	Beta-Hydroxybutyrate as Ca-Mg-salt, active	36 hours fasting, PAL 1.6
exogeneous ketone bodies, active	fasting, active	24 hours of ketone body supplements (Beta-Hydroxybutyrate as Ca-Mg-salt) additional to a normal diet (liquid meals), PAL 1.6
fasting, active	fasting, inactive	36 hours fasting, PAL 1.6
exogeneous ketone bodies, active	fasting, inactive	24 hours of ketone body supplements (Beta-Hydroxybutyrate as Ca-Mg-salt) additional to a normal diet (liquid meals), PAL 1.6
fasting, inactive	Beta-Hydroxybutyrate as Ca-Mg-salt, active	36 hours fasting, PAL 1.3
fasting, inactive	fasting, active	36 hours fasting, PAL 1.3
fasting, inactive	fasting, inactive	36 hours fasting, PAL 1.3

Primary Outcome Measures

Name	Time	Method
appetite control - GLP-1 concentration in plasma	24 hours	Glucose Like Peptide-1 concentration in plasma (24 hour AUC)
appetite control - PYY concentration in plasma	24 hours	Peptide YY concentration in plasma (24 hour AUC)
appetite control - ghrelin	24 hours	ghrelin concentration in plasma (24 hour AUC)
appetite control - satiety quotient	30 min	satiety quotient of standard test-breakfast after 24 hours of intervention
appetite control - subjective feelings of hunger	24 hours	measured with visual analogue scales (24 hour AUC). The scale consists of a 10 cm vertical line anchored with "not hungry at all" at the left side and with "extremely hungry" at the right side.

Secondary Outcome Measures

Name	Time	Method
macronutrient oxidation	24 hours	measured with indirect calorimetry in a metabolic chamber
repeatability of energy expenditure measurements	24 hours	repeated measurement of 24h-energy expenditure in a metabolic chamber on inactive isocaloric and fasting days
ß-Hydroxybutyrate concentration in serum	24 hours	24 hour ß-Hydroxybutyrate concentration in serum (AUC)
energy expenditure	24 hours	measured with indirect calorimetry in a metabolic chamber
glycemia - glucose AUC	24 hours	glucose AUC from continuous glucose monitoring data

Trial Locations

Locations (1)

Institute of Human Nutrition; 🇩🇪 Kiel, Germany