Effects of Two-weeks of Time Restricted Feeding on Basal and Postprandial Metabolism in Healthy Men (TRF)

University of Nottingham

Status: Completed

Conditions: Metabolic Health

Treatments: Behavioral: Caloric restriction; Behavioral: Time restricted feeding

Study type: Interventional

Funder types: Other

Identifiers

NCT03969745

19-1705

Details and patient eligibility

About

In the modern era, food access is widely available and it is not uncommon for the time between breakfast and a late night snack to exceed 14 hours. The investigators are interested in studying whether limiting this window to 8 hours will have any beneficial effects of human health as has been demonstrated in animal models. Eight men were asked to restrict their energy intake window to between 8 am and 4 pm for two weeks whilst maintaining their habitual diet (quantity and composition). Improvements in skeletal muscle and whole-body insulin sensitivity were observed but these were potentially confounded by an average weight loss of 1 kg. Therefore an additional control group was recruited to follow a daily caloric deficit of ~400 kilocalories without changing the timing of intake.

Full description

All participants were monitored for a one week baseline period to establish their habitual physical activity and dietary patterns. This was done using food diaries, interstitial glucose monitors and a combined heart rate + accelerometer device. Participants consumed a standardised evening meal ~12h before visiting the laboratory to assess their metabolic response to a liquid test meal (1g/kg bodyweight dextrose and 0.4g/kg bodyweight protein) using the arterio-venous forearm balance model. Dual-energy X-ray absorptiometry scans, indirect calorimetry measurements and fasted and postprandial vastus lateralis biopsies were also obtained.

From the next day, participants either restricted their daily energy intake window to between 8 am and 4 pm or were prescribed a caloric deficit diet (~400 kilocalories/day) for two weeks. Physical activity, interstitial glucose concentrations and dietary patterns were monitored throughout. After this, participants visited the laboratory again to assess changes in metabolism and body composition.

Enrollment: 16 patients

Sex: Male

Ages: 18 to 35 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Healthy male between 18 and 35 years old
• Body mass index between 18 and 27.5 kg.m^-2
• Regular breakfast consumer, 5 or more days per week
• Moderate physical activity level (PAL between 1.6 and 2)

Exclusion criteria

• Smoking
• Any metabolic (e.g. diabetes), endocrine (e.g. hyperthyroidism) or cardiovascular (heart or blood) abnormalities including hypertension.
• Clinically significant abnormalities on screening including ECG abnormalities
• Routine medication that may alter cardiovascular function and blood flow (e.g. blood pressure-lowering drugs or drugs that cause hypertension)
• High alcohol consumption (Routinely >4 units per day)
• Eating attitudes test (EAT-26) score > 20
• On an energy-restricted diet
• Significant body mass fluctuation in previous 3 months (>5%)

Trial design

Primary purpose: Prevention

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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16 participants in 2 patient groups

Time restricted feeding (TRF)

Experimental group

Description:

Participants restricted their daily energy intake window to between 8 am and 4 pm for two weeks. They were encouraged to not alter the quantity and composition of their diet or alter physical activity patterns.

Treatment:

Behavioral: Time restricted feeding

Caloric deficit

Active Comparator group

Description:

The investigators observed significant weight loss in the TRF group with participants reporting to consume \~400 kilocalories less per day. Therefore the investigators added a caloric deficit group to control for the effects of weight loss on metabolism. Total energy expenditure was measured for one week and was used to prescribe a 400 kilocalories/day energy deficit diet to follow for two weeks.

Treatment:

Behavioral: Caloric restriction