Time-restricted Eating (TRE) and Protein in Older Adults

NCT07314658 | Recruiting

• 1 other identifier: 361019
• Study Type: interventional
• Target: 80
• Locations: 1 country
• Sites: 1

Brief Summary

The aim this study is to investigate the effects of time-restricted eating (TRE) on body composition, muscle function and markers of metabolic health of adults over 60 years old. This study will compare different variations of TRE - with and without an additional protein. This study involves attending two study days at the University of Surrey for baseline and end-of-intervention measurement of body composition using a gold-standard dual energy x-ray absorptiometry (DEXA) scan; muscle function using hand grip strength and 30-second sit-to-stand tests; weight. A blood sample will be taken at each study visit to measure markers of lipid and glucose control, and insulin sensitivity. Participants will be randomly allocated to one of four study groups:

• control group: maintain habitual dietary patterns
• TRE group: fast for 16 hours overnight, eat between 12-8pm
• TRE + Protein (AM): fast for 16 hours overnight, eat between 12-8pm; take a 30g plant-based protein supplement in the morning
• TRE + Protein (PM): fast for 16 hours overnight, eat between 12-8pm; take a 30g plant-based protein supplement in the afternoon Participants will be asked to follow the intervention according to their allocated group for 8 weeks.

Conditions

Generally Healthy Adults Over 60 Years Old

Outcome Measures

Primary Outcomes (3)

• Change from baseline in body composition at 2 months using whole-body dual-energy x-ray absorptiometry (DEXA)

  Measured using whole-body dual-energy x-ray absorptiometry (DEXA) In addition to the above, body composition will also be assessed using Tanita Bioelectrical impedance analysis (BIA). Fat free and fat mass will be reported in kg.

  For 8 weeks of the assigned study intervention

• Change from baseline in muscle function at 2 months

  Measured using grip strength

  At the start and end of 8 weeks of the assigned study intervention

• Change from baseline in muscle function at 2 months

  Measured using 30-second sit-to-stand test.

  At the start and end of 8 weeks of the assigned study intervention

Secondary Outcomes (5)

• Change in fasting glucose control indicators

  At the start and end of 8 weeks of the assigned study intervention

• Change from baseline in insulin sensitivity at 2 months

  At the start and end of 8 weeks of the assigned study intervention

• Change from baseline in lipid metabolism at 2 months

  At the start and end of 8 weeks of the assigned study intervention

• Change from baseline in diet composition at 2 months

  At the start, mid-point (week 4) and end of 8 weeks of the assigned study intervention

• Feasibility of the assigned TRE intervention

  at the end of the 8 week intervention

Study Arms (4)

TRE

EXPERIMENTAL

Participants undertaking the TRE intervention

Other: TRE

ProtAM TRE

EXPERIMENTAL

Participants undertaking the ProtAM TRE intervention

Other: ProtAM TRE

ProtPM TRE

EXPERIMENTAL

Participants undertaking the ProtPM TRE intervention

Other: ProtPM TRE

Control

NO INTERVENTION

Interventions

ProtPM TRE OTHER

* Participants will be asked to follow a 16:8 TRE protocol, consuming all their daily within 8 hours, between 12 and 8pm, and fast for 16 hours overnight. * Outside of the eating window, participants will be allowed to consume energy-free drinks only, i.e. water, black tea/coffee, 0-calorie soft drinks. * In addition, they will be asked to consume a protein drink containing 30g protein in the afternoon, either 2 hours after their first meal or 2 hours before their last meal of the day.

Also known as: TRE + afternoon protein 'snack'

ProtPM TRE

TRE OTHER

* Participants will be asked to follow a 16:8 TRE protocol, consuming all their daily within 8 hours, between 12 and 8pm, and fast for 16 hours overnight. * Outside of the eating window, participants will be allowed to consume energy-free drinks only, i.e. water, black tea/coffee, 0-calorie soft drinks.

TRE

ProtAM TRE OTHER

* Participants will be asked to follow a 16:8 TRE protocol, consuming all their daily within 8 hours, between 12 and 8pm, and fast for 16 hours overnight. * Outside of the eating window, participants will be allowed to consume energy-free drinks only, i.e. water, black tea/coffee, 0-calorie soft drinks. * In addition, they will be asked to consume a protein drink containing 30g protein in the morning, 2 hours before the 8-hour eating window opens at 12pm (i.e. at 10am).

Also known as: TRE + morning protein 'snack'

ProtAM TRE

Eligibility Criteria

• Age: 60 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Gender: male and female
• Age range: 60 years or older
• Fasting for 12 or less hours on a daily basis
• BMI range: 23-30 kg/m2
• Weight stability: no more than 3kg weight gain or loss in the past 3 months
• Regular eating pattern, i.e. 3 meals a day
• Able to prepare the protein supplement

You may not qualify if:

• known renal impairment
• heart attack or stroke in the past three months
• continuous use of supplemental oxygen to manage a chronic pulmonary condition or heart failure
• rheumatoid arthritis
• Parkinson's disease
• active treatment for cancer in the past year
• insulin dependent diabetes mellitus
• taking medications that preclude fasting for 16 h
• actively trying or planning to lose weight
• history of an eating disorder
• outside of stated age or BMI range
• fasting for longer than 12 hours on a daily basis
• unable to prepare the protein supplement
• extreme morning/evening chronotype
• sleep disorders

Sponsors & Collaborators

• University of Surrey: lead

Study Sites (1)

University of Surrey

Guildford, GU2 7XH, United Kingdom

RECRUITING

MeSH Terms

Interventions

Trehalase

Intervention Hierarchy (Ancestors)

Disaccharidases; Glycoside Hydrolases; Hydrolases; Enzymes; Enzymes and Coenzymes

Central Study Contacts

Yana Petkova

CONTACT

+44 7513 679 635; yp00228@surrey.ac.uk

Dr Collins

CONTACT

a.collins@surrey.ac.uk

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: November 26, 2025
• First Posted: January 2, 2026
• Study Start: December 1, 2025
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): July 1, 2027
• Last Updated: January 2, 2026

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)