Pea protein vs. whey: which preserves muscle better during weight loss?
NCT ID NCT04123938
First seen Jun 26, 2026 · Last updated Jun 26, 2026
Summary
This pilot study tested whether pea protein can help people with obesity preserve muscle mass while losing weight, compared to whey protein. Sixty adults aged 30 to 50 followed a weight loss regimen and took either pea protein, whey protein, or a non-protein control. Researchers measured changes in muscle mass, strength, and function.
What this could mean
Our plain-language read of the trial. This is informational only, not medical advice or a prediction.
- Active substance
- pea protein
- What this could lead to
- If it works, this could point toward a plant-based alternative to whey protein for maintaining muscle during weight loss.
- What could go wrong
- This is a small pilot study with only 60 participants, so results may not apply to everyone. It also compares pea protein to whey protein, not to a placebo, so any benefit may be similar to other protein sources.
This is an AI summary of the original study and may miss details. Read our disclaimer.
Study facts
What this study's own registry entry says, in plain language.
- Phase
-
Not a phased trial
Phase numbers describe drug development. The registry uses this when they do not apply, as it does for trials of devices, procedures or behaviour changes, and for observational studies.
- Participants
-
60 people
The number who actually took part.
- Started
-
Oct 2019
- Finished
-
May 2023
- Lead sponsor
-
Other sponsor
The registry's catch-all category, for sponsors it does not file as a company, a government agency, or a research network.
Who can take part
This study's own entry requirements. Only the study team can say for certain whether you qualify.
- Ages
-
30 to 50 years
- Sex
-
Anyone
- Healthy volunteers
-
Accepted
You do not need to have the condition being studied to take part.
Show the full entry requirements Hide the full entry requirements
Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.
Inclusion Criteria: 1. Male, or non-pregnant, non-lactating female, 30 to 50 years of age; 2. BMI \>30 and body weight does not exceed the capacity of the DEXA (350 lbs); 3. Fat mass \>23% for males and \>32% for females (determined at the screening visit via bioelectrical impedance); 4. Willing to maintain a stable level of activity while participating in the study; 5. Plasma creatinine ≤265 µmol/L; 6. Plasma LDL-cholesterol \<5 mmol/L; 7. Aspartate aminotransferase \<160 U/L, and alanine aminotransferase \<150 U/L; 8. Glycated hemoglobin \<6.5%; 9. Blood pressure \<160 mmHg systolic and \<100 mmHg diastolic; 10. Stable regime if taking vitamin and mineral/dietary/herbal supplements for the past 1 month and while participating in the study; 11. Not taking protein supplements for the past month and willing to continue doing so for the duration of the study; 12. Has not donated blood or blood products (e.g. platelets) during the past 2 months and willing to continue doing so while participating in the study; 13. Female participants of child-bearing potential must agree to use a highly effective method of contraception throughout the study; 14. Not participating in another dietary intervention trial for the past month and willing to not start another dietary intervention trial or weight loss program for the duration of this study; 15. Willing to comply with the protocol requirements and procedures; 16. Willing to provide informed consent. Exclusion Criteria: 1. Has experienced a cardiovascular event (e.g. heart attack, stroke) or had a surgical procedure for cardiovascular disease (e.g. bypass, stent), presence of diabetes, chronic renal disease, liver disease (with exception of fatty liver), rheumatoid arthritis, immune disorder or disease (e.g. multiple sclerosis, leukemia), cancer in the previous 5 years, neurological disorders, gastrointestinal disorders or gastrointestinal surgery or bariatric surgery, or liposuction; 2. Taking medications for blood glucose management; 3. Taking medications or natural health products/supplements associated with weight gain or weight loss (e.g. prednisone, certain cold medications); 4. Body weight that has not been stable (± 5%) over the past 3 months; 5. History of gastrointestinal reactions or allergies to peas, pea protein, whey protein or maltodextrin, or to one or more ingredients in the beverages and foods that will be provided which significantly limits the number of items that can be used for delivery of the protein powders or maltodextrin; 6. Current (within the past 30 days) bacterial, viral or fungal infection; 7. Uncontrolled hypothyroidism; 8. Uncontrolled blood pressure; 9. Bleeding disorder; 10. Any acute medical condition or surgical intervention within the past 3 months; 11. Cigarette/cigar smoking or use of tobacco products within the last 12 months or during participation in the study; 12. Consumption of \>10 alcoholic beverages per week or \>2 alcoholic beverages per day within the last 3 months or while participating in the study; 13. Drug and/or alcohol abuse; 14. Psychological disorder(s); 15. Unable to obtain blood sample at the screening or week 0 visits.
Get updates
Get notified about this study
Sign up to get updates when this study changes or when new studies for Obesity are added.
Genom att skicka in godkänner du våra Användarvillkor
Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
-
I.H Asper Clinical Research Institute, St. Boniface Hospital
Winnipeg, Manitoba, R2H 2A6, Canada
More trials for these conditions
Other studies related to the condition(s) this trial covers.
- Which exercise dose best helps kids with metabolic syndrome?
- Custom knee guides put to the test in obese patients
- A pill for obesity? early human trial puts MDR-001 to the test
- Can a weekly shot help people who still struggle with weight after bariatric surgery?
- Do GLP-1 Weight-Loss drugs change how teens eat and feel?
- Can electrical muscle stimulation boost exercise benefits after menopause?