We are currently recruiting for a randomised controlled trial during which participants will be allocated and asked to consume one of 3 breakfast types for 4-weeks. The study will include two laboratory visits before and one after the 4-week period.

Recent studies within our research group have helped to establish humans' relationship between their health and eating or skipping breakfast. We would now like to know whether the contents of your breakfast changes this relationship. In particular, we are interested whether substituting some carbohydrate for protein at breakfast results in a change in energy balance and metabolic health.

Furthermore, we will study what the difference in macronutrient composition of a breakfast has on energy balance and ones ability to undertake physical activity.

What's involved in the study

You will be asked to stick to a particular breakfast plan for four weeks. There are three plans, one of which you will be randomly allocated:

• Carbohydrate rich – where a breakfast rich in carbohydrates is consumed daily prior to 10.00am.
• Protein enriched – where we remove some of the carbohydrate content of the carbohydrate rich breakfast and replace it with whey protein, to be consumed daily prior to 10.00am.
• No breakfast – where no energy is consumed until 12pm (midday) each day.

We will focus on aspects of health including body weight, physical activity, energy intake, circulating blood hormone (for example, insulin) and metabolite concentrations (for example, glucose), as well as changes in blood genes that control your body clock.

To participate in the study, you will be asked to visit our laboratory on three occasions:

Preliminary visit

This will last approximately 45 minutes, during which we will measure how much energy you burn at rest and ask you to undergo a short (approximately 12 minutes) non-exhaustive exercise test.

Pre-intervention meal testing

We will feed you a test breakfast followed by a test lunch and we will take blood samples to measure your response to each meal. This will last approximately 6 hours.

Post-intervention meal testing

This will be identical to the pre-intervention meal test.

In the four weeks of the intervention we will provide you with a food diary and an activity monitor to assess your energy intake and energy expenditure.

Please note: Due to the current COVID-19 pandemic, participants will not be required to attend the university for the study until the social distancing guidance permits safe reopening of the laboratories to research volunteers.

Eligibility

To be eligible to participate in this study you must:

• be male or female, healthy, and aged between 18 to 65 years old
• have a body mass index between 18.5 and 29.9 kg/m (squared)

Some things that may make you ineligible for the study include:

• a diagnosed metabolic disease (for example, type 1 or type 2 diabetes)
• use of substances which may pose undue personal risk to you or introduce bias into the study
• if you do not conform to a standard sleep-wake cycle (for example, working night shifts)
• any reported change of body mass greater than 3% in the last 6 months

What you'll get for taking part

The main benefit of taking part in this study is that you will receive detailed feedback about your physiological health. The feedback will include a detailed analysis of your diet, including calorie intake and macronutrient composition, detailed breakdown of your metabolic rate and energy expenditure, feedback on your circulating metabolites and hormones in your blood.

If allocated to either breakfast consuming condition we will provide you with four weeks of pre-weighed breakfasts to be consumed daily. Furthermore, you will be making a potentially invaluable contribution to scientific knowledge that will pioneer new findings in this area of research. Due to the exploratory nature of the study, we are not able to claim the exact health benefits when allocated to each of the interventions on the study.

Confidentiality

All identifiable data will be stored in a locked cabinet or in a password protected spreadsheet on the University’s servers. For this reason, only the lead investigator and principal supervisor will be able to identify participants. As a participant, you will be able to access your own data upon request.