“Beans proteins are not good for muscle growth as animal proteins”

NutritionExerciseSupplementsAgingMetabolism

4/5 evidence score14 peer-reviewed studies

What the science says

Bean proteins generally have a less favorable essential amino acid profile and lower digestibility compared to animal proteins, leading to a lower muscle protein synthetic response per gram. However, research indicates that a high-protein, exclusively plant-based diet, when adequately supplemented or strategically combined, can support muscle mass and strength accrual comparably to a protein-matched mixed diet.

Full analysis

Multiple studies and reviews consistently indicate that plant proteins, including those from beans, typically have a less complete amino acid profile (lower essential amino acids like leucine, methionine, and lysine) and lower digestibility compared to animal proteins. This often translates to a reduced post-prandial muscle protein synthesis response when consumed gram-for-gram. However, a key human randomized controlled trial demonstrated that when total protein intake is high and strategically managed (e.g., through supplementation with soy protein isolate), a plant-based diet can support muscle mass and strength gains comparably to an omnivorous diet. Therefore, while bean proteins may be inherently 'less good' in terms of quality per gram, their effectiveness for muscle growth can be optimized through careful dietary planning and adequate total intake.

Key studies

Higher Muscle Protein Synthesis Rates Following Ingestion of an Omnivorous Meal Compared with an Isocaloric and Isonitrogenous Vegan Meal in Healthy, Older Adults.

Pinckaers PJ et al. · The Journal of nutrition · 2024

Ingestion of a whole-food omnivorous meal containing beef resulted in approximately 47% higher postprandial muscle protein synthesis rates compared to an isonitrogenous whole-food vegan meal in healthy, older adults.

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High-Protein Plant-Based Diet Versus a Protein-Matched Omnivorous Diet to Support Resistance Training Adaptations: A Comparison Between Habitual Vegans and Omnivores.

Hevia-Larraín V et al. · Sports medicine (Auckland, N.Z.) · 2021

A high-protein (~1.6 g/kg/day) exclusively plant-based diet (with soy protein isolate supplementation) was not different from a protein-matched mixed diet (with whey protein supplementation) in supporting muscle strength and mass accrual in untrained young men undergoing resistance training.

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

van Vliet S et al. · The Journal of nutrition · 2015

Plant-based proteins like soy and wheat result in a lower muscle protein synthetic response compared to animal-based proteins, attributed to lower digestibility and a relative lack of specific essential amino acids, particularly leucine.

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“Beans proteins are not good for muscle growth as animal proteins”

What the science says

Full analysis

Key studies

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