Soy Protein

What does the research say?

Research on soy protein for building muscle mass shows that it can be effective, especially when consumed in adequate amounts and combined with exercise [1] [11] . While some studies suggest that whey protein may lead to greater muscle gains compared to soy protein, especially in the short term [2] [7] [10] , other research indicates that these differences may diminish with longer-term supplementation and higher protein intakes [1] [13] . Some studies have found no significant difference between soy and whey protein in promoting muscle growth when matched for leucine content [15] . Moreover, soy protein supplementation may be particularly beneficial for younger individuals and may be an effective alternative to animal proteins when total protein intake is sufficient (≥ 1.6 g/kg/day) [11] [13] .

The papers used in this article do not explicitly mention side effects of soy protein.

Therefore, no specific side effects are listed.

[1] Protein Source and Muscle Health in Older Adults: A Literature Review.

This review examines the role of different protein sources, including soy protein, on muscle health in older adults. It discusses the benefits of soy protein for muscle mass and strength, especially in vegetarians and vegans, and compares its effectiveness to whey protein.

[2] Supplemental protein in support of muscle mass and health: advantage whey.

This review discusses the role of protein, particularly whey protein, in promoting muscle mass and overall health. It highlights the advantages of whey protein over other protein sources like soy due to its amino acid content and rapid digestibility.

[3] The Skeletal Muscle Anabolic Response to Plant- versus Animal-Based Protein Consumption.

This review compares the anabolic response of skeletal muscle to plant-based proteins, such as soy, versus animal-based proteins. It discusses factors that may contribute to the potentially lower anabolic properties of plant proteins, such as digestibility and amino acid composition.

[4] The Anabolic Response to Plant-Based Protein Ingestion.

This review examines the anabolic response to plant-based protein ingestion, including soy protein. It discusses how factors like amino acid composition and digestion kinetics influence the muscle protein synthetic response compared to animal-based proteins.

[5] Health Promotion Effects of Soy Isoflavones.

This review focuses on the various health-promoting effects of soy isoflavones, including their potential anti-obesity, anti-diabetic, and anti-cancer properties.

[6] Protein content and amino acid composition of commercially available plant-based protein isolates.

This study analyzes the protein content and amino acid composition of various plant-based protein isolates, including soy protein. It highlights the relatively high essential amino acid content of soy protein compared to other plant-based options.

[7] Ingestion of whey hydrolysate, casein, or soy protein isolate: effects on mixed muscle protein synthesis at rest and following resistance exercise in young men.

This study compared the effects of whey, casein, and soy protein on muscle protein synthesis in young men at rest and after resistance exercise. It found that whey protein stimulated muscle protein synthesis to a greater degree than soy or casein.

[8] The beneficial therapeutic effects of plant-derived natural products for the treatment of sarcopenia.

This review explores the therapeutic potential of plant-derived products, including soy protein and its isoflavones, for the treatment of sarcopenia. It highlights the benefits of soy protein in improving muscle strength and reducing inflammation.

[9] The effect of animal versus plant protein on muscle mass, muscle strength, physical performance and sarcopenia in adults: protocol for a systematic review.

This is a protocol for a systematic review that will compare the effects of animal versus plant proteins, including soy protein, on muscle-related outcomes. It discusses the potential for soy protein to be as effective as animal proteins in building muscle mass and strength.

[10] Myofibrillar muscle protein synthesis rates subsequent to a meal in response to increasing doses of whey protein at rest and after resistance exercise.

This study investigated the dose-response relationship between whey protein intake and muscle protein synthesis. It compared whey to casein and soy and found a greater acute response with whey.

[11] Effect of Soy Protein Supplementation on Muscle Adaptations, Metabolic and Antioxidant Status, Hormonal Response, and Exercise Performance of Active Individuals and Athletes: A Systematic Review of Randomised Controlled Trials.

This systematic review examines the effects of soy protein supplementation on various aspects of exercise performance and muscle adaptations. It suggests that soy protein may be an effective alternative to whey protein in promoting muscle mass and strength gains, particularly in young populations.

[12] Effect of whey and soy protein supplementation combined with resistance training in young adults.

This study compared the effects of whey and soy protein supplementation combined with resistance training in young adults. It found that both protein sources increased lean tissue mass and strength similarly.

[13] No Difference Between the Effects of Supplementing With Soy Protein Versus Animal Protein on Gains in Muscle Mass and Strength in Response to Resistance Exercise.

This meta-analysis compared the effects of soy protein versus animal protein supplementation on gains in muscle mass and strength in response to resistance exercise. It found no significant difference between the two protein sources.

[14] Effects of Whey, Soy or Leucine Supplementation with 12 Weeks of Resistance Training on Strength, Body Composition, and Skeletal Muscle and Adipose Tissue Histological Attributes in College-Aged Males.

This study examined the effects of whey, soy, or leucine supplementation with resistance training on various outcomes in college-aged males. It found that soy protein did not provide added benefit over placebo for increasing muscle mass or strength.

[15] No Significant Differences in Muscle Growth and Strength Development When Consuming Soy and Whey Protein Supplements Matched for Leucine Following a 12 Week Resistance Training Program in Men and Women: A Randomized Trial.

This study compared soy and whey protein supplements matched for leucine content during a resistance training program. It found no significant differences in muscle growth and strength development between the two groups.

[16] Inflammaging and Skeletal Muscle: Can Protein Intake Make a Difference?

This review discusses the role of protein intake, including soy and whey protein, in mitigating the effects of inflammaging on skeletal muscle. It highlights the potential anti-inflammatory and antioxidative effects of these proteins.

[17] Daidzein Inhibits Muscle Atrophy by Suppressing Inflammatory Cytokine- and Muscle Atrophy-Related Gene Expression.

This study investigated the effects of daidzein, a soy isoflavone, on muscle atrophy. It found that daidzein inhibited muscle atrophy by suppressing inflammatory cytokines and muscle atrophy-related genes.

[18] Additive impact of soy protein dietary intake and exercise on visceral fat mass reduction and mitochondrial complex I activation in skeletal muscle.

This study investigated the combined effects of soy protein intake and exercise on fat mass reduction and mitochondrial function in mice. It found that soy protein combined with exercise significantly reduced fat mass and enhanced mitochondrial complex I activity.