Effect of 24 h Severe Energy Restriction on Appetite Regulation and Ad-libitum Energy Intake

Study Overview
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Brief Summary
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Long term maintenance of weight loss is generally poor, which is at least partly due to increased feelings of hunger associated with restricting what can be eaten. Intermittent severe energy restriction is a novel dietary strategy that requires individuals to consume a very-low energy diet for 1-4 days per week, allowing normal feeding patterns to be adopted on the other days in the week. However, the effect of a consuming a very-low energy diet on appetite regulation, which might represent a key marker of long-term adherence to dieting, has not been determined. This study aimed to assess the effects of severely restricting energy intake for 24 h on markers of appetite regulation, energy balance and metabolism compared to an adequate energy trial.

Official Title
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Effect of 24 h Severe Energy Restriction on Appetite Regulation and Ad-libitum Energy Intake in Lean Males and Females

Conditions
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Deficiency; Calorie

Intervention / Treatment
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* Other: Energy intake


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: non-smoker, not currently dieting, weight stable for >6 months (self-reported), no known history of cardiovascular or renal disease. Exclusion Criteria: food allergies, dislike or intolerance of study foods and drinks, irregular eating patterns, use of medication that could influence hormone concentrations, excessive alcohol consumption (>4 units/day), intensive training schedule (>10 h/week)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 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: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Energy balance<br>Intervention day diet containing 100% of estimated energy requirements | Other: Energy intake<br> <br> |
| Experimental: Energy restriction<br>Intervention day diet containing 25% of estimated energy requirements | Other: Energy intake<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ad-libitum energy intake | Measured at laboratory-based meals and weight food records | 48 hours | 
| Subjective appetite | Measured using visual analogue scales | 48 hours | 
| Plasma acylated Ghrelin | Measured using ELISA from venous blood samples | 24 hours | 
| Plasma active glugagon-like peptide 1 | Measured using ELISA from venous blood samples | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma insulin | Measured using ELISA from venous blood samples | 24 hours | 
| Plasma glucose | Measured using colorimetric assay from venous blood samples | 24 hours | 
| Plasma Non-esterified Fatty acids | Measured using colorimetric from venous blood samples | 24 hours | 
| Energy expenditure | Measured under resting conditions using indirect calorimetry | 24 hours | 
| Fat oxidation | Measured under resting conditions using indirect calorimetry | 24 hours | 
| carbohydrate oxidation | Measured under resting conditions using indirect calorimetry | 24 hors |