Plant vs Whey Protein for Protein Metabolism

Overseen By Marielle P Engelen, PhD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Texas A&M University

Must not be taking: Corticosteroids, Protein supplements

Disqualifiers: Diabetes, Heart disease, Cancer, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 5

Duration: 4 days

100 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications. However, you cannot participate if you are using long-term oral corticosteroids or have used a short course of oral corticosteroids within 4 weeks before the study.

What data supports the effectiveness of the treatment in the clinical trial titled 'Plant vs Whey Protein for Protein Metabolism'?

Research shows that soy protein can improve muscle function and has a high nutritional value, with 91% digestibility and 78% net protein utilization. Additionally, a blend of dairy and vegetable proteins, including soy and pea, offers a balanced amino acid profile, which is important for muscle growth and maintenance. ^{1 2 3 4 5}

Is soy protein isolate safe for human consumption?

Research indicates that soy protein isolate is generally safe for human consumption, as studies have shown no significant adverse effects on blood lipids or platelet aggregation in normal men. However, some individuals with milk protein enterocolitis may also react to soy protein, suggesting a potential for allergic reactions in sensitive individuals. ^{1 6 7 8 9}

How does the treatment using plant and whey protein isolates differ from other treatments for protein metabolism?

This treatment is unique because it compares plant-based proteins like pea and soy with animal-based whey protein, focusing on their effects on protein metabolism. The study highlights the sustainability of plant proteins and their potential to support protein synthesis, although whey protein shows a higher immediate increase in essential amino acids. ^{6 8 10 11 12}

What is the purpose of this trial?

The researchers overall objective is to determine whether plant and animal protein based proteins affect the anabolic responses across aging populations differently due to specific changes in the essential amino acids (EAA) and non-essential amino acids (NEAA) kinetic responses. The researchers central hypothesis is that a high EAA to NEAA ratio in a protein meal is related to higher anabolic response to the meal. The researchers also hypothesize that the type of NEAA in a protein meal also affects the anabolic capacity of the meal. The researchers rationale is that finding the amino acid composition of a meal that will maximally induce protein anabolism will guide novel nutritional approaches to prevent and treat sarcopenia, thereby reducing both overall economic burden and improving individual patient outcomes.

Research Team

Marielle Engelen, Ph.D.

Principal Investigator

Texas A&M University

Nicolaas E Deutz, Ph.D.

Principal Investigator

Texas A&M University

Eligibility Criteria

This trial is for older adults with sarcopenia, which is a condition involving loss of muscle mass and strength. Participants should be interested in how different protein sources affect their metabolism.

Inclusion Criteria

Stable body-weight (±5%) for the past 3 months

Willingness and ability to comply with the protocol

I am between 50 and 95 years old.

Exclusion Criteria

Active dependence of alcohol or drugs

Established daily diet of vegetarian / vegan composition

Use of protein or amino acids containing nutritional supplements within 5 days of the first study day

Timeline

Screening

Participants are screened for eligibility to participate in the trial

1 day

1 visit (in-person)

Treatment

Participants receive dietary supplements of either whey protein, soy protein, pea protein, or placebo over 4 study days

4 days

4 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Treatment Details

Interventions

• Organic Pea Protein Isolate
• Soy Protein Isolate (90% Protein)
• Whey Protein Isolate 90%

Trial Overview The study aims to compare the effects of plant-based proteins (soy and pea) and animal-based whey protein on muscle building responses in aging individuals. It also looks at whether water, used as a placebo, has any effect.

Participant Groups

Group I: Sarcopenic male old older adults Experimental Treatment 4 Interventions

Dietary Supplement: Whey Protein Isolate 90%. Commercially available Dietary Supplement: Soy Protein Isolate (90% Protein). Commercially available Dietary Supplement: Organic Pea Protein Isolate. Commercially available Dietary Supplement: Placebo - Water

Group II: Sarcopenic female old older adults Experimental Treatment 4 Interventions

Dietary Supplement: Whey Protein Isolate 90%. Commercially available Dietary Supplement: Soy Protein Isolate (90% Protein). Commercially available Dietary Supplement: Organic Pea Protein Isolate. Commercially available Dietary Supplement: Placebo - Water

Group III: Healthy male older adults Experimental Treatment 4 Interventions

Dietary Supplement: Whey Protein Isolate 90%. Commercially available Dietary Supplement: Soy Protein Isolate (90% Protein). Commercially available Dietary Supplement: Organic Pea Protein Isolate. Commercially available Dietary Supplement: Placebo - Water

Group IV: Healthy male old older adults Experimental Treatment 4 Interventions

Dietary Supplement: Whey Protein Isolate 90%. Commercially available Dietary Supplement: Soy Protein Isolate (90% Protein). Commercially available Dietary Supplement: Organic Pea Protein Isolate. Commercially available Dietary Supplement: Placebo - Water

Group V: Healthy female older adults Experimental Treatment 4 Interventions

Dietary Supplement: Whey Protein Isolate 90%. Commercially available Dietary Supplement: Soy Protein Isolate (90% Protein). Commercially available Dietary Supplement: Organic Pea Protein Isolate. Commercially available Dietary Supplement: Placebo - Water

Group VI: Healthy female old older adults Experimental Treatment 4 Interventions

Dietary Supplement: Whey Protein Isolate 90%. Commercially available Dietary Supplement: Soy Protein Isolate (90% Protein). Commercially available Dietary Supplement: Organic Pea Protein Isolate. Commercially available Dietary Supplement: Placebo - Water

Who Is Running the Clinical Trial?

Texas A&M University

Lead Sponsor

Trials

156

Recruited

28,900+

Findings from Research

In a study involving 50 adult rats over 8 weeks, both whey protein isolate (WPI) and soy protein concentrate (SPC) were found to enhance muscle performance more effectively than milk protein isolate (MPI), with significant increases in contraction rates.

The improvements in muscle function from soy and whey proteins occurred without changes in muscle mass or fiber size, suggesting that these protein sources may enhance muscle function through mechanisms other than just increasing muscle size.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Chronic dietary supplementation with soy protein improves muscle function in rats. Khairallah, RJ., O'Shea, KM., Ward, CW., et al.[2018]

In a study involving 14 healthy men, daily intake of 20 g of soy protein isolate (SPI) for 4 weeks significantly reduced triglycerides and remnant-like particle cholesterol levels by 13.4% and 9.8%, respectively, indicating SPI's potential to improve lipid profiles.

However, SPI intake also led to a significant decrease in vitamin E levels by 9.7%, suggesting that vitamin E supplementation may be necessary for individuals consuming high amounts of soy protein to maintain adequate vitamin E status.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of soy protein on levels of remnant-like particles cholesterol and vitamin E in healthy men. Higashi, K., Abata, S., Iwamoto, N., et al.[2019]

The study found that three different plant-based protein blends resulted in 30-40% lower levels of essential amino acids in the blood compared to Whey Protein Isolate (WPI), indicating they are not bio-equivalent.

Despite the lower overall amino acid response, two of the plant-based blends showed similar timing for peak leucine levels compared to WPI, suggesting they may still have some anabolic potential for muscle growth.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Differential Responses of Blood Essential Amino Acid Levels Following Ingestion of High-Quality Plant-Based Protein Blends Compared to Whey Protein-A Double-Blind Randomized, Cross-Over, Clinical Trial. Brennan, JL., Keerati-U-Rai, M., Yin, H., et al.[2020]

The study found that the true oro-ileal digestibility of soy protein isolate (SPI) nitrogen in humans is 91%, indicating a high level of digestibility.

After ingestion, 86% of the absorbed SPI amino acids were utilized for nonoxidative disposal, leading to a net postprandial protein utilization of 78%, which is comparable to 92% of the nutritional value of milk protein concentrate.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Nutritional value of [15N]-soy protein isolate assessed from ileal digestibility and postprandial protein utilization in humans. Mariotti, F., Mahé, S., Benamouzig, R., et al.[2018]

A new protein blend (P4) consisting of 35% whey, 25% casein, 20% soy, and 20% pea was tested on 14 healthy elderly subjects and showed similar amino acid availability to casein and whey, but better than soy and pea.

The P4 blend provided a more balanced amino acid profile, with higher levels of key amino acids like leucine and methionine compared to soy and pea, indicating its potential benefits for patients requiring medical nutrition.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Amino Acid Availability of a Dairy and Vegetable Protein Blend Compared to Single Casein, Whey, Soy, and Pea Proteins: A Double-Blind, Cross-Over Trial. Liu, J., Klebach, M., Visser, M., et al.[2023]

Native isoelectrically precipitated soy protein isolate (SPI) made with natural ingredients like amaranth lye and lemon extract has a high protein content (91.21%) and comparable digestibility to SPI made with synthetic chemicals.

The natural SPI contains higher levels of beneficial amino acids like methionine and cysteine, lower anti-nutritional factors, and more minerals like potassium, making it a healthier alternative to synthetic SPI.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of synthetic and natural extraction chemicals on yield, composition and protein quality of soy protein isolates extracted from full-fat and defatted flours. Chamba, MV., Hua, Y., Murekatete, N., et al.[2020]

In a study of 43 patients with suspected milk- and/or soy-protein enterocolitis, both powdered and liquid soybean formulas elicited similar rates of adverse reactions, with 33% reacting to powdered soy and 30% to liquid soy.

The findings suggest that many patients with milk protein enterocolitis also have soy protein enterocolitis, and that the order of food challenges may influence reaction rates, indicating a potential local immune response to the protein isolates.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Prospective oral food challenge study of two soybean protein isolates in patients with possible milk or soy protein enterocolitis. Burks, AW., Casteel, HB., Fiedorek, SC., et al.[2023]

Partial replacement of soy protein isolate (SPI) with okara dietary fiber (ODF) enhances the gelling properties of SPI gels, improving their hardness and texture, especially in varying salt concentrations.

The study found that ODF reduces SPI's self-aggregation and increases disulfide bond formation, which contributes to better gel quality and higher dietary fiber content in the final product.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Gel properties of okara dietary fiber-fortified soy protein isolate gel with/without NaCl. Lv, Y., Wang, J., Xu, L., et al.[2022]

In a study of 20 male subjects consuming either a soy protein isolate or casein supplement for 28 days, soy protein significantly increased plasma isoflavone levels, reaching concentrations much higher than those typically found in Japanese diets.

Despite the increase in isoflavones, soy protein supplementation did not significantly affect platelet aggregation or cholesterol levels, suggesting that higher isoflavone levels alone may not reduce heart disease risk factors in individuals with normal cholesterol levels.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A soy protein isolate rich in genistein and daidzein and its effects on plasma isoflavone concentrations, platelet aggregation, blood lipids and fatty acid composition of plasma phospholipid in normal men. Gooderham, MH., Adlercreutz, H., Ojala, ST., et al.[2018]

Isolated soy protein (Supro-620) has a high nutritional value comparable to egg protein, as shown in nitrogen balance studies with healthy young male subjects, indicating it can effectively support protein maintenance.

Supplementation with L-methionine did not enhance the nitrogen balance benefits of soy protein, suggesting that methionine is not a limiting factor for adults consuming isolated soy protein.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Evaluation of the protein quality of an isolated soy protein in young men: relative nitrogen requirements and effect of methionine supplementation. Young, VR., Puig, M., Queiroz, E., et al.[2023]

In a study involving male Sprague-Dawley rats, both isolated proteins (dairy whey and soy) and protein blends enhanced muscle protein synthesis (MPS) after meals, indicating their effectiveness in promoting muscle growth.

Blend 2, which contained a specific ratio of whey, caseinate, and soy, showed a significantly higher peak in muscle protein synthesis compared to whey protein alone at 135 minutes post-meal, suggesting that certain protein blends may be more beneficial for muscle recovery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A soy, whey and caseinate blend extends postprandial skeletal muscle protein synthesis in rats. Butteiger, DN., Cope, M., Liu, P., et al.[2021]

In a study involving 9 healthy young men, whey protein isolate (WHEY) was found to produce a significantly greater increase in essential amino acids (IAA) in the bloodstream compared to pea (PEA) and fava bean (FAVA) protein isolates, suggesting that WHEY may be more effective for muscle building and recovery.

Despite the lower immediate anabolic response of PEA and FAVA compared to WHEY, incorporating plant-sourced protein isolates into diets can promote sustainability, making them a valuable alternative to animal-sourced proteins.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

An Investigation of the Protein Quality and Temporal Pattern of Peripheral Blood Aminoacidemia following Ingestion of 0.33 g·kg-1 Body Mass Protein Isolates of Whey, Pea, and Fava Bean in Healthy, Young Adult Men. Kozior, M., Davies, RW., Amigo-Benavent, M., et al.[2023]

References

1. United States pubmed.ncbi.nlm.nih.gov

Chronic dietary supplementation with soy protein improves muscle function in rats. [2018]

2. Japan pubmed.ncbi.nlm.nih.gov

Effects of soy protein on levels of remnant-like particles cholesterol and vitamin E in healthy men. [2019]

3. Switzerland pubmed.ncbi.nlm.nih.gov

Differential Responses of Blood Essential Amino Acid Levels Following Ingestion of High-Quality Plant-Based Protein Blends Compared to Whey Protein-A Double-Blind Randomized, Cross-Over, Clinical Trial. [2020]

4. United States pubmed.ncbi.nlm.nih.gov

Nutritional value of [15N]-soy protein isolate assessed from ileal digestibility and postprandial protein utilization in humans. [2018]

5. Switzerland pubmed.ncbi.nlm.nih.gov

Amino Acid Availability of a Dairy and Vegetable Protein Blend Compared to Single Casein, Whey, Soy, and Pea Proteins: A Double-Blind, Cross-Over Trial. [2023]

6. India pubmed.ncbi.nlm.nih.gov

Effects of synthetic and natural extraction chemicals on yield, composition and protein quality of soy protein isolates extracted from full-fat and defatted flours. [2020]

7. England pubmed.ncbi.nlm.nih.gov

Prospective oral food challenge study of two soybean protein isolates in patients with possible milk or soy protein enterocolitis. [2023]

8. England pubmed.ncbi.nlm.nih.gov

Gel properties of okara dietary fiber-fortified soy protein isolate gel with/without NaCl. [2022]

9. United States pubmed.ncbi.nlm.nih.gov

A soy protein isolate rich in genistein and daidzein and its effects on plasma isoflavone concentrations, platelet aggregation, blood lipids and fatty acid composition of plasma phospholipid in normal men. [2018]

10. United States pubmed.ncbi.nlm.nih.gov

Evaluation of the protein quality of an isolated soy protein in young men: relative nitrogen requirements and effect of methionine supplementation. [2023]

11. England pubmed.ncbi.nlm.nih.gov

A soy, whey and caseinate blend extends postprandial skeletal muscle protein synthesis in rats. [2021]

12. Switzerland pubmed.ncbi.nlm.nih.gov

An Investigation of the Protein Quality and Temporal Pattern of Peripheral Blood Aminoacidemia following Ingestion of 0.33 g·kg-1 Body Mass Protein Isolates of Whey, Pea, and Fava Bean in Healthy, Young Adult Men. [2023]