New research is challenging long-held beliefs about protein quality, suggesting that plant-based proteins may be just as effective as animal sources for muscle building and maintenance. This is provided you consume adequate amounts and maintain consistent resistance training.
According to nutrition expert Alan Aragon, recent controlled studies comparing vegan and omnivore diets have revealed surprising results. He spoke about it in a recent podcast with Andrew Huberman.
In the groundbreaking research, participants following completely vegan regimens showed no significant differences in muscle size and strength gains compared to omnivores over a 12-week period. This is despite consuming significantly fewer essential amino acids and branch chain amino acids overall.
“The vegan diet overall had significantly less essential amino acid content and significantly less branch chain amino acid content,” Aragon explains. “But apparently the resistance training stimulus is robust enough to make protein effects almost secondary.”
The key appears to be hitting specific protein targets. Both groups in the study consumed 1.6 grams of protein per kilogram of body weight daily (approximately 0.7 grams per pound). The vegan group supplements with soy protein to reach these levels. This challenges the common assumption that animal proteins are inherently superior for muscle development.
A follow-up study by Montene and colleagues using mycoprotein (a fungus-based protein) yielded similar results, with plant-based participants matching omnivores for muscle and strength gains. Remarkably, the mycoprotein even outperformed milk protein for muscle protein synthesis in acute studies.
“Gram for gram, as a group, animal proteins are higher quality,” Aragon acknowledges. “They have a higher proportion of essential amino acids and more anabolic-driving amino acids like leucine.” However, he emphasizes that these advantages may be negligible when total daily protein intake is optimized and combined with proper resistance training.
The research suggests that the resistance training stimulus itself may be the primary driver of muscle adaptation, with protein quality becoming a secondary concern when minimum thresholds are met. This finding has significant implications for athletes and fitness enthusiasts who choose plant-based diets for ethical, environmental, or health reasons.
For those following vegan protocols, the studies indicate that reaching higher protein targets through strategic supplementation can effectively compensate for the lower amino acid density of plant sources. Soy protein, in particular, performed well in multiple trials, contradicting common misconceptions about its effectiveness.
The consistency of results across multiple trials suggests that well-planned vegan diets can support muscle development and maintenance when combined with adequate resistance training and proper caloric intake. The bottom line is, regardless of protein source, hitting your total daily protein macros while maintaining consistent resistance training appears to be the primary determinant of success in muscle building and body composition goals.