Obesity Prevention
Conditions
Keywords
Chrononutrition, Time-Restricted Eating, Energy Balance, Glycaemic Control
Brief summary
This study compared the metabolic response to three different eating windows (morning fast,12pm-8pm; evening fast, 8am-4pm; control, 8am-8pm).
Detailed description
Humans have evolved as a diurnal species, internally governed by the circadian system, which dictates our hormone regulation. 'Chrononutrition' is a sub-discipline which combines food timing with circadian physiology. The most popular method of time-restricted feeding in the UK is to skip breakfast. However, data from several meta-analysis have shown that skipping breakfast is associated with weight gain and insulin resistance, likely due to eating later into the evening/night and therefore, out of sync with our circadian rhythm. Recent research has shown that skipping dinner (evening fasting) has improved markers of cardio-metabolic health in clinical populations, although these are typically from longer-term studies. Despite these promising findings, it is not yet known whether these findings are population specific. Therefore, the investigators are interested in examining the metabolic response pre and post-intervention to see whether these promising findings can translate into a healthy population. Furthermore, the investigators will be monitoring subjective appetite, energy intake, and expenditure to assess whether there is any short-term adaptation to a specific feeding window.
Interventions
BEHAVIORALEvening Fasting
Participants will undertake acute evening fasting (feeding between 8am-4pm) for one day. After which they will attend the laboratory, following a 16 h fast, where baseline measures will be taken and the response to a standardised meal will take place. The participant will also have an opportunity to feed ad-libitum before they leave the laboratory.
BEHAVIORALMorning Fasting
Participants will undertake an acute morning fasting trial (feeding between 12pm-8pm). After which, participants will visit the laboratory the following day, after a 16 h fast, where baseline measures will be taken and the response to a standardised meal will take place. The participant will also have an opportunity to feed ad-libitum before they leave the laboratory.
BEHAVIORALControl
Participants will undertake an acute standard western feeding pattern (feeding between 8am-8pm). After which, participants will visit the laboratory the following day, after a 12 h fast, where baseline measures will be taken and the response to a standardised meal will take place. The participant will also have an opportunity to feed ad-libitum before they leave the laboratory.
Sponsors
Loughborough University
Nottingham Trent University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
NONE
Intervention model description
The study design is a randomised, controlled, crossover design in which participants undertake three conditions in a randomised order with at least one week in between trials.
Eligibility
Sex/Gender
MALE
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* recreationally active * non-smokers * non-dieting * weight stable (self-reported for \>6 months) * were not consuming any medication known to affect appetite or physical activity
Exclusion criteria
* Smokers * \>10 hours per week physical activity * Have dieted within the past 6 months * Excessive alcohol consumption (\>14 units/week) * Use of medication or supplements that may affect hormone concentrations.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Glycaemic Control | 0 hour (Pre breakfast), 1 hour, 2 hour, 3.5 hour | A metabolic assessment lasting 3.5 hours will take place following a standardised, laboratory-based meal. The investigators will be taking periodic capillary and venous blood samples to measure post-prandial glucose and insulin, which together comprise 'glycaemic control'. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Energy expenditure | Activity recorded across day 1 standardisation and day 2 (lab visit and post lab visit) | Energy expenditure will be measured via a chest-worn device (Actiheart) which combines heart rate and accelerometry to gauge calories expended. |
| Visual analogue scale for subjective ratings of appetite | 0 hour (pre-breakfast), 1 hour, 2 hour, 3 hour, 4 hour (post breakfast during lab visit) | Subjective appetite will be measured on mobile devices via a software which replicates a 100mm visual analogue scale. The scale is divided into subscales of different appetite perceptions including: hunger, fullness, desire to eat and prospective food consumption. This will be measured on a scale of 0-100 (0 - none at all) (100 - a lot). |
| Acylated Ghrelin (Appetite hormone) | 0 hour (pre breakfast), 1 hour, 2 hour, and 3 hour post breakfast | Acylated Ghrelin will be measured from the venous samples taken during the post-prandial period following the standardised meal. |
| Energy Intake | 3.5 hour following breakfast | Energy intake will be measured both during lab and outside of the laboratory when the participants are free-living. During lab, energy intake will be measured through ad-libitum feeding buffet where 20 minutes will be permitted to eat as much or as little as they desire, until 'comfortably full and satisfied', followed by post-feeding measurement of the remaining food. |
| Carbohydrate Oxidation | 0 hour (pre breakfast), 1 hour, 2 hour, 3 hour post breakfast | Investigators will be collecting expired air into Douglas bags, and measuring the VO2 and VCO2 concentration to calculate carbohydrate oxidation. |
| Fat Oxidation | 0 hour (pre breakfast), 1 hour, 2 hour, 3 hour | Investigators will be collecting expired air into Douglas bags, and measuring the VO2 and VCO2 concentration to calculate fat oxidation. |
| PYY (Appetite hormone) | 0 hour (pre-breakfast), 1 hour, 2 hour, and 3 hour post breakfast | Acylated Ghrelin will be measured from the venous samples taken during the post-prandial period following the standardised meal. |
Countries
United Kingdom
Outcome results
None listed