RecruitingNAINTERVENTIONAL

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

This study investigates how time-restricted eating (TRE), a pattern where you eat all your meals within a specific window each day, affects the bodies of healthy adults over 60. We want to see how it might impact body composition (like muscle and fat), muscle strength, and important health markers related to blood sugar and fats. We'll be comparing different ways of doing TRE, including whether adding a protein supplement in the morning or afternoon changes the results. The goal is to understand if and how these eating patterns can benefit older adults' health.

At a glance

Status

Recruiting

Phase

Sponsor

University of Surrey

Enrolment target

Start

01 Dec 2025

Estimated completion

01 Jul 2027

Generally Healthy Adults Over 60 Years Old

What is this study about?

This research is looking into a type of eating plan called 'time-restricted eating', or TRE for short. This means you eat all your meals within a certain number of hours each day and then fast for the rest of the time, often overnight. The study aims to understand how this way of eating might affect people over 60, specifically looking at things like their body make-up (how much muscle and fat they have), how strong their muscles are, and important markers that tell us about their overall health, such as blood sugar and cholesterol levels.

We're trying to find out if TRE can have a positive impact on these areas, which are really important for staying healthy and active as we get older. We're also comparing a few different approaches to TRE. For some people, we'll see what happens if they just stick to the eating window. For others, we'll see if adding a protein drink in either the morning or afternoon makes any difference to the results. This helps us understand the best ways to use TRE, especially when it comes to supporting muscle health.

By taking part, you would help us learn more about how different eating patterns affect our bodies as we age. This knowledge could eventually help healthcare professionals give more specific and helpful advice to older adults about diet and healthy living.

Key takeaways

Researchers are studying time-restricted eating (TRE) in healthy adults over 60.
The study looks at effects on body composition, muscle strength, and general health.
Participants will follow an eating pattern for 8 weeks, with or without a protein supplement.
Two study visits to the University of Surrey are required for health checks.
Participation helps scientists understand healthy ageing and diet.

Who may be eligible?

This study is looking for healthy men and women aged 60 or older. You should usually eat three meals a day and not typically fast for longer than 12 hours. Your Body Mass Index (BMI) should be between 23 and 30, and your weight should have been stable recently, meaning no more than 3kg gained or lost in the last three months.

There are certain health conditions or situations that would mean you couldn't take part. For example, if you have kidney problems, have had a recent heart attack or stroke (in the last three months), or have certain long-term conditions like rheumatoid arthritis or Parkinson's disease. You also wouldn’t be able to join if you're taking medications that mean you can't fast for 16 hours, actively trying to lose weight, or have struggled with an eating disorder in the past.

We also need participants who are able to prepare a protein supplement if they are in one of the protein groups. If you have extreme sleeping patterns, regular skip meals, or have difficulty having blood samples taken, this study might not be suitable for you.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 60 years old or older?
Do you generally eat around 3 meals a day and not fast for more than 12 hours?
Has your weight been stable (no more than 3kg gained or lost) in the last 3 months?
Do you have any major health conditions like kidney problems or recent heart attack/stroke?
Are you comfortable with having blood samples taken?

Answer every question to see your result.

What does participation involve?

If you decide to take part in this study, you'll be involved for a total of 8 weeks. During this time, you'll need to visit the University of Surrey twice: once at the start and once at the end of the 8-week period. Each visit will involve several assessments.

These assessments include a special scan called a DEXA scan, which is a gold-standard way to measure your body composition (how much muscle, bone, and fat you have). We'll also check your muscle strength using simple tests like hand grip strength and how many times you can stand up from a chair in 30 seconds. Your weight will also be measured. At each visit, a small blood sample will be taken to check important health markers, such as those related to blood sugar and cholesterol levels.

After your first visit, you'll be randomly assigned to one of four groups. This means you won't choose which group you're in, it's decided by chance, like flipping a coin. One group will continue eating as they normally do. The other three groups will follow a period of time-restricted eating (eating between 12pm and 8pm, fasting for 16 hours overnight). Two of these TRE groups will also take a plant-based protein supplement, either in the morning or in the afternoon, according to their assigned group. You'll follow your group's plan for 8 weeks until your final study visit.

Potential risks and benefits

Taking part in research always has potential benefits and risks. A potential benefit of this study could be learning more about various eating patterns and their impact on your health. While we cannot guarantee any direct health benefits, the information gained could be valuable for future advice on healthy ageing. The risks involved are generally low, such as discomfort from blood sampling or the DEXA scan, which uses a very small amount of radiation. Following a specific eating pattern might feel challenging for some participants. You are free to withdraw from the study at any time, for any reason, without it affecting your usual medical care.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

University of Surrey
Verified postcode
Guildford, United Kingdom· Recruiting

Common questions

What is 'time-restricted eating'?

It's when you eat all your meals within a specific number of hours each day and then don't eat for the rest of the time, often overnight.

How long will I be in the study?

The study will last for 8 weeks in total.

Do I have to take a protein supplement?

Not everyone in the study will take a protein supplement; it depends on which group you are randomly assigned to.

What are the study visits like?

You'll have two visits at the University of Surrey for measurements like body scans, strength tests, and blood samples.

Will I know which group I'm in?

Yes, you will know which study group you have been assigned to after your first visit.

How to find out more

Yana Petkova

yp00228@surrey.ac.uk +44 7513 679 635 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.