The effect of hydrolysed pea protein on postprandial blood glucose profile in healthy adults
| ISRCTN | ISRCTN13927108 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN13927108 |
| ClinicalTrials.gov (NCT) | Nil known |
| Clinical Trials Information System (CTIS) | Nil known |
| Protocol serial number | 2148 |
| Sponsor | University of Leeds |
| Funder | Libyan Embassy |
- Submission date
- 05/05/2025
- Registration date
- 22/05/2025
- Last edited
- 06/05/2025
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Nutritional, Metabolic, Endocrine
Plain English summary of protocol
Background and study aims
After eating a meal, especially one high in carbohydrates like bread or pasta, our blood sugar levels naturally rise. For some people, especially those at risk of type 2 diabetes, these rises can be too high or last too long, which can be harmful over time. What we eat alongside carbohydrates can affect how our body handles sugar. Proteins, including those from plants, may help reduce the rise in blood sugar after eating. Pea protein is a plant-based protein that is popular for being sustainable, allergy-friendly, and suitable for vegetarians and vegans. This study is particularly interested in hydrolysed pea protein, which is a type of protein that has been broken down into smaller units called peptides. These smaller fragments may have enhanced effects on digestion and blood sugar compared to regular pea protein isolate. The study aims to find out whether hydrolysed pea protein helps reduce blood sugar levels after a meal, and how it compares to regular pea protein, whey protein (from animal source), and a control drink (water). It will also look at other substances in the blood that are linked to how the body controls sugar and appetite
Who can participate?
Healthy adult volunteers
What does the study involve?
The study compares four conditions: a carbohydrate meal with either 30 g pre-hydrolysed pea protein drink, 30 g non-hydrolysed pea protein isolate drink, 30 g whey protein drink, or water (Control). Each participant attended four randomly allocated blinded sessions over two weeks, with standardized carbohydrate content and a minimum of 2 days between sessions for washout.
What are the possible benefits and risks of participating?
No benefits and risks given at publication
Where is the study run from?
University of Leeds, School of Food Science and Nutrition, UK
When is the study starting and how long is it expected to run for?
November 2024 to September 2025
Who is funding the study?
Libyan Embassy, UK (PhD Scholarship to Arig Elbira)
Who is the main contact?
Arig Elbira, fs19aaae@leeds.ac.uk
Contact information
Public, Principal investigator
School of Food Science and Nutrition
Leeds
LS2 9JT
United Kingdom
 ORCID ID |
0000-0001-6705-5709 |
|---|---|
| Phone | +44 (0)113-34-30268 |
| c.bosch@leeds.ac.uk |
Scientific
School of Food Science and Nutrition
Leeds
LS2 9JT
United Kingdom
| ORCID ID |
0000-0002-0551-0865 |
|---|---|
| Phone | +44 (0)113 343 2876 |
| fs19aaae@leeds.ac.uk |
Public
School of Food Science and Nutrition
Leeds
LS2 9JT
United Kingdom
| ORCID ID |
0000-0003-4154-8630 |
|---|---|
| Phone | +44 (0)113-34-36546 |
| a.j.hernandezalvarez@leeds.ac.uk |
Study information
| Primary study design | Interventional |
|---|---|
| Study design | Single-centre double-blinded randomized controlled crossover trial |
| Secondary study design | Randomised cross over trial |
| Study type | Participant information sheet |
| Scientific title | Postprandial glycaemic response to hydrolysed pea protein in healthy adults: a randomised, double-blind, controlled, crossover trial |
| Study acronym | HYPP-GLY Study |
| Study objectives | Hydrolysed pea protein will reduce postprandial blood glucose levels more effectively than non-hydrolysed pea protein when co-ingested with a carbohydrate-rich meal in healthy adults. |
| Ethics approval(s) |
Approved 01/04/2025, Business, Environment, Social Sciences (BESS+ FREC) Faculty Research Ethics Committee (FREC) (University of Leeds, Woodhouse Ln, Woodhouse, Leeds, LS29JT, United Kingdom; +44(0)113 343 0524; ResearchEthics@leeds.ac.uk), ref: 2148 |
| Health condition(s) or problem(s) studied | Reduction of postprandial glycaemia in healthy adult |
| Intervention | The study compared four conditions: a carbohydrate meal consumed together with (1) 30 g pre-hydrolysed pea protein drink , (2) 30 g non-hydrolysed pea protein isolate drink, (3) 30 g whey protein drink, and (4) water (Control). The total carbohydrate content was standardized to 75 g across all test conditions (white bread and maltodextrin). All four drinks were flavour-masked to ensure a double-blind design. The order of interventions was randomized using pre-generated sequences from an online program. Each participant attended four separate sessions over approximately two weeks, with a minimum of 2 days between sessions to allow for washout. |
| Intervention type | Supplement |
| Primary outcome measure(s) |
Postprandial glucose levels will be measured using two methods: |
| Key secondary outcome measure(s) |
1. Insulin and satiety hormones will be measured from capillary blood samples collected via the finger-prick method at baseline and every 15 min for a total of 3h post-meal |
| Completion date | 01/09/2025 |
Eligibility
| Participant type(s) | Healthy volunteer |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Upper age limit | 56 Years |
| Sex | All |
| Target sample size at registration | 16 |
| Key inclusion criteria | 1. Adults aged between 18 – 56 years old 2. Normal rage of body weight with BMI <30 kg/m2. 3. Be in general good health (with no known food allergies/intolerances) 4. Normal range of fasting blood glucose levels (<5.6 mmol/L) 5. Not taking any medication/s known to affect blood pressure, blood glucose (like diabetic medication) or cholesterol. |
| Key exclusion criteria | 1. BMI >30 kg/m² 2. Elevated fasting blood glucose (above 5.5 mmol/L) 3. Pregnancy 4. Smoking 5. Chronic diseases 6. Allergies and medication use known to affect food digestion, appetite, food sensory perception, or glucose metabolism 7. Individuals who engage in regular high-intensity athletic training or competitive sports 8. Recent blood donation (<3 months) 9. Participation in simultaneous studies |
| Date of first enrolment | 07/04/2025 |
| Date of final enrolment | 30/05/2025 |
Locations
Countries of recruitment
- United Kingdom
- England
Study participating centre
Leeds
LS2 9JT
United Kingdom
Results and Publications
| Individual participant data (IPD) Intention to share | Yes |
|---|---|
| IPD sharing plan summary | Published as a supplement to the results publication |
| IPD sharing plan | The data generated and analysed during this study will be published as averages rather than individual data or participant identity to ensure anonymity. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
Editorial Notes
06/05/2025: Study's existence confirmed by the Business, Environment, Social Sciences (BESS+ FREC) Faculty Research Ethics Committee (FREC).
