Very Low-calorie Diet & Cardiometabolic Health

Not Applicable

Completed

• Conditions: Healthy
• Interventions: Other: Very low calorie diet with low protein content (VLCD-LP group); Other: Very low calorie diet with high protein content (VLCD-HP group)

• Registration Number: NCT06560996
• Lead Sponsor: University of Nottingham

Brief Summary

To investigate the effects of a short-term (1-week) nutritional intervention in healthy individuals using very low-calorie (fasting-mimicking) diets with different protein content on markers of cardiometabolic health and autophagy.

Detailed Description

The aim of this project is to investigate the metabolic effects of a short-term (1-week) nutritional intervention in healthy humans using very low-calorie (fasting-mimicking) diets with low and high protein content on key cardiometabolic outcomes (with blood glucose as a primary outcome) and autophagy, oxidative stress, inflammation, functional measures of cardiovascular health, body composition, and faecal markers for gut microbiome diversity (secondary outcomes).

Study Timeline

• Study Start: 2024-01-31
• Study First Submitted: 2024-06-26
• Status Verified: 2024-08
• Study First Submitted QC: 2024-08-16
• Study First Posted: 2024-08-19
• Primary Completion: 2024-09-30
• Study Completion: 2025-01-31
• Last Update Submitted: 2025-03-25
• Last Update Posted: 2025-03-30

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 46

Inclusion Criteria

• Participant is willing and able to give informed consent for participation in the study
• Participant is willing and able to comply with the requirements of the study protocol
• Aged between 18 and 65 years
• Healthy individual

Exclusion Criteria

• A BMI <18 or >35 kg/m2
• Regularly skipping breakfast
• On an energy-restricted diet
• Taking medication to control appetite
• Eating Attitudes Test (EAT-26) score >20 as self-reported marker of symptoms and concerns characteristic of eating disorders
• Active metabolic (e.g. diabetes), endocrine (e.g. hyperthyroidism) or cardiovascular (e.g. heart or blood) abnormalities including hypertension or heart failure
• Having taken part in a research study in the last 3 months involving invasive procedures or an inconvenience allowance

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Very low calorie diet with low protein content (VLCD-LP group)	Very low calorie diet with low protein content (VLCD-LP group)	7 days very low-calorie diet (850 kcal per day) with low protein content (10% energy from protein, 45% from carbohydrate and 45% from plant-based fat)
Very low calorie diet with high protein content (VLCD-HP group)	Very low calorie diet with high protein content (VLCD-HP group)	7 days very low-calorie diet with high protein content (30% energy from protein, 45% from carbohydrate and 25% from plant-based fat)

Primary Outcome Measures

Name	Time	Method
Fasting blood glucose	Day 0, Day 8	To determine the impact of very low-calorie diets on fasting blood glucose concentration and the addition of low and high protein

Secondary Outcome Measures

Name	Time	Method
Measure circulatory autophagy marker Beclin-1	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on Beclin-1 measured using Western Blotting and real-time polymerase chain reaction (PCR) techniques.
Measure circulatory autophagy marker Microtubule-associated protein 1A/1B-light chain 3 (LC3)	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on LC3 measured using Western Blotting and PCR techniques.
Measure cardiometabolic health via insulin levels	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on insulin using enzyme linked immunosorbant assays.
Measure circulatory inflammation via Tumour Necrosis factor alpha-1 (TNF-alpha) levels	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on serum TNFalpha levels using enzyme linked immunosorbant assays.
Measures of cardiovascular health with autonomic function (heart rate)	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on autonomic function (heart rate response to postural change and rhythmic breathing).
Measure circulatory autophagy proteins (ATGs)	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on ATGs measured using Western Blotting and real-time PCR techniques.
Measure circulatory inflammation via Insulin like-growth factor-1 (IGF-1) levels	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on serum IGF-1 levels using enzyme linked immunosorbant assays.
Functional measures of cardiovascular health with heart rate	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on heart rate and heart rate variability.
Faecal markers for gut microbiome diversity	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on microbiome diversity using stool analysis techniques (16S Metagenomic Sequencing)
Urine markers of protein metabolism	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on urinary markers of protein metabolism (ratio of urea to creatinine) using established biochemical (spectrophotometric) methods
Measure circulatory inflammation via C-reactive protein levels	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on serum C-reactive protein levels using enzyme linked immunosorbant assays.
Measure of cardiovascular health with blood pressure	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on supine and standing blood pressure (both diastolic and systolic).
Functional measures of cardiovascular health	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on arterial stiffness using suprasternal notch-femoral pulse wave velocity by ArterioGraph.
Measures of cardiovascular health with autonomic function (blood pressure)	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on autonomic function (blood pressure \[diastolic and systolic\] response to postural change and rhythmic breathing).
Body composition	Day 0, Day 8	To determine the impact of very low-calorie diets with low and high protein content on body fat mass and lean mass using DEXA (dual energy x-ray absorptiometry).

Trial Locations

Locations (1)

HC International SA; 🇨🇭 Weggis, Switzerland