Plain English Summary
Background and study aims
Recent studies show that foods of the same overall nutrient composition but eaten in different food structures result in different digestive effects, and subsequently different health effects. This is becoming known as the food matrix effect. Dairy foods are a particular example of this effect. A number of studies have shown that dairy fat eaten in the form of cheese has a lower cholesterol-increasing effect compared to the same fat eaten as butter, even when the other nutrients, such as protein and calcium, are controlled for. There are lots of theories about this, and evidence suggests that calcium and the type of protein may have an effect. Many of the studies are 6 weeks in length and look at the change in LDL cholesterol levels over time. However, LDL-cholesterol levels are just one factor for heart disease risk. Another factor is raised levels of circulating fatty acids after eating, known as post-prandial lipaemia. The aim of this study is to look at what happens in the hours after eating dairy fat in three different forms: as cheese, as a reduced fat cheese plus butter, and as butter, protein and calcium. It is thought that the cheese 'matrix' will result in lower circulating fatty acids compared to butter, and that the cheese and butter will give a result somewhere in between.
Who can participate?
What does the study involve?
Participants eat three meals in a random order with a 5-7 day break in between meals. Meal 1 is 120g full fat cheddar cheese and a slice of low-fibre white toast. Meal 2 is 120g reduced fat cheddar cheese and a slice of low-fibre white toast. Meal 3 is 30g calcium caseinate powder. Circulating fatty acids and blood glucose are measured from blood samples collected at fasting, and hourly, on the hour, for the 6-hour period after eating.
What are the possible benefits and risks of participating?
There are no known benefits to participating. Potential risks are discomfort or bruising from the blood sampling, and the risk of finding the study food unpleasant.
Where is the study run from?
University College Dublin (Ireland)
When is the study starting and how long is it expected to run for?
February 2018 to August 2018
Who is funding the study?
Who is the main contact?
Dr Emma Feeney
Post-prandial randomised controlled trial to examine the postprandial effects of dairy fat within different matrices
Dairy fat, when eaten in varying levels of a cheese matrix, will have different outcomes on postprandial lipids.
Human Research Ethics Committee in University College Dublin, 24/01/2018, ref. LS-17-103
Single-centre randomised cross-over intervention trial
Primary study design
Secondary study design
Randomised cross over trial
Patient information sheet
Not available in web format, please use the contact details to request a patient information sheet
Subjects will receive three meals which contain dairy fat in varying levels of a cheese matrix, with a slice of toast as a carrier, in a random order with a 5-7 day washout period in between meals. Due to the nature of the meals, the arms cannot be masked.
Arm 1: 120g full fat cheddar cheese and a slice of low-fibre white toast
Arm 2: 120g reduced fat cheddar cheese and a slice of low-fibre white toast
Arm 3: 30g calcium caseinate powder
Primary outcome measures
Circulating fatty acids measured with a Randox Daytona from blood samples collected at fasting, and hourly, on the hour, for the 6-hour postprandial period
Secondary outcome measures
Blood glucose measured with a Randox Daytona from blood samples collected at fasting, and hourly for the 6-hour post-prandial period
Overall trial start date
Overall trial end date
Participant inclusion criteria
1. Fasting triglycerides <2.5
2. BMI 18-35
Target number of participants
Participant exclusion criteria
1. Familial hypercholesteraemia
2. Fasting triglycerides greater than 2.5
3. Any diagnosed metabolic disorder such as diabetes type 1 or 2
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
University College Dublin
Science Centre South Belfield
D04 V1 W8
Trial participating centre
Food for Health Ireland
UCD Centre for Molecular Innovation and Drug Discovery Science Centre South, Belfield
D04 V1 W8
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
The results will be prepared for publication and submitted to relevant journals in the field. Other additional documents will not be made available at this time.
IPD sharing statement
The datasets generated during and/or analysed during the current study are not expected to be made available. The data will be stored on a password-protected computer (encrypted) as per UCD data protection recommendations.
Intention to publish date
Participant level data
Not expected to be available
Results - basic reporting