Plain English Summary
Background and study aims
Milk is an excellent source of protein and other key nutrients. Many proteins found in milk are caseins, which can be broken down into protein fragments (peptides). Bioactive peptides are protein fragments that have a beneficial effect on health. There is evidence to suggest that casein bioactive peptides have beneficial effects on health, in particular the cardiovascular (circulatory) system and immune system. Some research has suggested that milk-derived protein supplements (hydrolysates) may have potential health benefits in terms of managing blood sugar levels. The aim of this study is to examine the ability of three different types of protein drinks to help maintain good blood sugar control.
Who can participate?
Healthy adults aged between 40 and 65 years.
What does the study involve?
Participants are randomly allocated receive three treatments in a random order. Each treatment lasts for three days and there is day period between each treatment where participants follow their normal diet. The first treatment involves drinking a protein drink containing intact casein twice a day at breakfast time and in the evening for three days. The second and third treatments involve drinking a protein drink containing protein hydrolysate A and protein hydrolysate B respectively (two different milk-derived protein supplements). The study period lasts for a total of 14 days, during which participants wear a special device which automatically and continuously monitors their blood sugar levels.
What are the possible benefits and risks of participating?
There are no direct benefits to the participants but this study should help researchers gain a better understanding of how ingredients that are potentially beneficial work. There are no notable risks involved with participating.
Where is the study run from?
University College Dublin (Ireland)
When is the study starting and how long is it expected to run for?
June 2016 to June 2018
Who is funding the study?
Enterprise Ireland (Ireland)
Who is the main contact?
Professor Lorraine Brennan
Examination of the effect of milk proteins on glycemic management
A protein hydrolysate will help glycemic management over and above the intact parent protein.
UCD Human Ethics committee, 12/04/2016, ref: LS-16-13-Brennan
Randomised cross over intervention study
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
Participants will be randomised to receive three treatments in a random order. There will be a washout period of 2 days between each arm, where participants follow their normal diet.
Treatment 1: Protein drink containing intact casein
Treatment 2: Protein drink containing protein hydrolysate A
Treatment 3: Protein drink containing protein hydrolysate B
In all treatments, the protein drink will be consumed twice daily for 3 days as part of study breakfast and evening meals.
Follow up involves wearing the FreeStyle Libre continuous glucose monitoring system for 14 days in order to monitor glucose levels.
Primary outcome measure
Glucose levels are measured using the FreeStyle Libre continuous glucose monitoring system continuously for the 14 days of the study.
Secondary outcome measures
Glucose control throughout the day is measured using the FreeStyle Libre continuous monitoring system continuously for the 14 days of the study.
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
Healthy adults aged 40-65 years
Target number of participants
Participant exclusion criteria
1. BMI < 25kg/m2, BMI >35kg/m2,
2. Any diagnosis of disease or the taking of any medication (except the OCP)
3. Pregnancy or lactation
4. An allergy or intolerance to dairy or wheat products
5. Known allergy to medical grade adhesive
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
University College Dublin
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
Planned publication in a high-impact peer reviewed journal.
IPD Sharing plan:
The current data sharing plans for the current study are unknown and will be made available at a later date.
Intention to publish date
Participant level data
To be made available at a later date
Basic results (scientific)
2019 results in: https://www.ncbi.nlm.nih.gov/pubmed/30608606