A pilot study comparing the effects of pea protein versus whey protein on the preservation of muscle mass and functionality in individuals undertaking a weight loss regimen.

A single site, double-blind, randomized clinical trial designed to compare the effects of pea protein or whey protein or maltodextrin supplementation on muscle mass and functionality in males and females with obesity undertaking a weight loss regimen. Eligible participants will be randomized to one of the three groups (pea protein, whey protein, maltodextrin) and will be asked to attend 3 in-person clinic visits (0, 6, and 12 weeks) for blood and urine collection and assessments of muscle mass and muscle function. A separate visit for screening and for a fasting blood sample, as well as a Pre-Study visit and a meeting with a registered dietitian, will be required.

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.