Vegan vs. omnivore. It’s one of the oldest debates in bodybuilding, with even most sports nutritionists favoring an animal-based diet over one consisting of only plant-based foods. But a new study is challenging the conventional wisdom.

The study compared two groups of healthy, young men with one group eating omnivorous protein and the other eating only plant-based protein. (Both groups supplemented with synthetic creatine.) Over the course of weight-training programs the scientists noticed no significant difference in muscle or strength gains. The study’s authors concluded: “Omnivorous and vegan diets can support comparable rested and exercised daily myofibrillar protein synthesis rates in healthy young adults consuming a high-protein diet. This translates to similar skeletal muscle adaptive responses during prolonged high-volume resistance training irrespective of dietary protein provenance.”

vegan vs. omnivore
Nuts are a good source of vegan protein.

Exercise scientist Brad Schoenfeld, PhD, said this about the findings on Instagram today:

Previously, I held the belief that animal proteins were superior to plant-based proteins due to lower amounts of certain essential amino acids (particularly leucine). Theoretically, the opinion seemed sound. However, emerging research employing more relevant designs indicates otherwise. This new study shows similar muscular adaptations with plant-vs animal-based protein combined with RT [resistance training] provided adequate daily protein intake to support hypertrophy (~2 g/kg/day). Based on these findings and other recent research, it appears that protein quality essentially becomes moot when consumption is sufficiently high.

A couple points of note: First, the study supplemented both groups with creatine; thus, it isn’t clear how results may have changed without the supplemental creatine (and if creatine supplementation may be needed to maximize anabolism in those consuming a plant-based diet). Second, it tends to be more difficult for vegans to obtain the necessary amounts of protein from whole foods; thus, some individuals may require additional protein supplementation to achieve adequate intake. Regardless, the body of literature seems to indicate a paradigm shift is in order for protein prescription, with plant- and animal-based proteins similarly effective choices to maximize hypertrophy. 💪🏽

After some Instagram commenters were hostile to the findings, Schoenfeld posted:

I’m not sure why some people seem to be triggered by these findings. The take-home here is simply that people have options. The emerging data indicate that if you prefer to consume a plant-based diet you can achieve similar amounts of hypertrophy as with an animal-based diet, albeit it may be more challenging to consume the amount of daily protein needed and thus (perhaps) require supplementation. Alternatively, if you prefer to eat an animal-based continue to do so; that’s a viable choice. And for the record, I’m not a vegan; I just report the evidence.

See also: Best Vegan and Vegetarian Bodybuilders Ever