The effect of hydrolysed pea protein on postprandial blood glucose profile in healthy adults

ISRCTN ISRCTN13927108
DOI https://doi.org/10.1186/ISRCTN13927108
Secondary identifying numbers 2148
Submission date
05/05/2025
Registration date
22/05/2025
Last edited
06/05/2025
Recruitment status
No longer recruiting
Overall study status
Ongoing
Condition category
Nutritional, Metabolic, Endocrine
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year

Plain English Summary

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

Dr Christine Bosch
Public, Principal Investigator

School of Food Science and Nutrition
Leeds
LS2 9JT
United Kingdom

ORCiD logoORCID ID 0000-0001-6705-5709
Phone +44 (0)113-34-30268
Email c.bosch@leeds.ac.uk
Mrs Arig Ebira
Scientific

School of Food Science and Nutrition
Leeds
LS2 9JT
United Kingdom

ORCiD logoORCID ID 0000-0002-0551-0865
Phone +44 (0)113 343 2876
Email fs19aaae@leeds.ac.uk
Dr Alan Javier Hernandez Alvarez
Public

School of Food Science and Nutrition
Leeds
LS2 9JT
United Kingdom

ORCiD logoORCID ID 0000-0003-4154-8630
Phone +44 (0)113-34-36546
Email a.j.hernandezalvarez@leeds.ac.uk

Study information

Study designSingle-centre double-blinded randomized controlled crossover trial
Primary study designInterventional
Secondary study designRandomised cross over trial
Study setting(s)University/medical school/dental school
Study typePrevention, Efficacy
Participant information sheet See study outputs table
Scientific titlePostprandial glycaemic response to hydrolysed pea protein in healthy adults: a randomised, double-blind, controlled, crossover trial
Study acronymHYPP-GLY Study
Study hypothesisHydrolysed 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

ConditionReduction of postprandial glycaemia in healthy adult
InterventionThe 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 typeSupplement
Primary outcome measurePostprandial glucose levels will be measured using two methods:
1. Continuous Glucose Monitor devices (CGMs) for a total of 14 days
2. Glucometer using strips at baseline and every 15 min for a total of 3h post-meal
Secondary outcome measures1. 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
2. Blood pressure will be measured using an automatic device at baseline and every 30 min for a total of 3h post-meal
3. Satiety score will be measured using a Visual Analogue Scale (VAS) at baseline and every 30 min for a total of 3h post-meal
Overall study start date01/11/2024
Overall study end date01/09/2025

Eligibility

Participant type(s)Healthy volunteer
Age groupAdult
Lower age limit18 Years
Upper age limit56 Years
SexBoth
Target number of participants16
Participant inclusion criteria1. 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.
Participant exclusion criteria1. 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
Recruitment start date07/04/2025
Recruitment end date30/05/2025

Locations

Countries of recruitment

  • England
  • United Kingdom

Study participating centre

School of Food Science and Nutrition
University of Leeds, Woodhouse Ln, Woodhouse
Leeds
LS2 9JT
United Kingdom

Sponsor information

University of Leeds
University/education

Woodhouse Lane
Leeds
LS2 9JT
England
United Kingdom

Phone +44 (0)113 343 2876
Email foodug@leeds.ac.uk
Website https://www.leeds.ac.uk
ROR logo "ROR" https://ror.org/024mrxd33

Funders

Funder type

Government

Libyan Embassy

No information available

Results and Publications

Intention to publish date15/07/2025
Individual participant data (IPD) Intention to shareYes
IPD sharing plan summaryPublished as a supplement to the results publication
Publication and dissemination planPlanned publication in a peer-reviewed journal by July 2025
IPD sharing planThe data generated and analysed during this study will be published as averages rather than individual data or participant identity to ensure anonymity.

Editorial Notes

06/05/2025: Study's existence confirmed by the Business, Environment, Social Sciences (BESS+ FREC) Faculty Research Ethics Committee (FREC).