Posted on 04/21/2025 6:05:19 PM PDT by Red Badger
In a nutshell
Vegan diets support muscle protein synthesis at the same rate as omnivorous diets when protein intake is matched (1.1-1.2g per kg of body weight).
How you distribute protein throughout the day (evenly across meals vs. mostly at dinner) doesn’t significantly impact muscle growth.
Vegan dieters reported higher energy levels and less fatigue, while omnivorous dieters reported greater meal satisfaction.
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CHAMPAIGN, Ill. — Forget what you’ve heard at the gym about needing chicken breasts and steaks to build muscle. Science just delivered a win for plant-based eaters everywhere. Researchers found that vegan diets support muscle growth just as effectively as those loaded with animal proteins, according to a new study.
“Bro-science” at fitness centers has long claimed animal proteins are essential for serious gains. This misconception has fueled a massive supplement industry pushing whey protein and other animal-derived products as muscle-building necessities. The new research published in Medicine & Science in Sports & Exercise says is great news for those interested in moving more towards plant-based diets.
The Science Behind the Study
The University of Illinois Urbana-Champaign team, led by Andrew Askow and Nicholas Burd, discovered that when protein intake is matched, there’s no difference in how quickly muscles create new proteins—regardless of whether that protein comes from plants or animals.
The researchers studied 40 healthy, active young adults who followed either vegan or omnivorous diets for nine days while completing resistance training. Both groups consumed the same amount of protein daily (about 1.1-1.2 grams per kilogram of body weight). Using techniques involving heavy water and muscle samples, the scientists directly measured muscle protein synthesis rates—the process responsible for muscle growth.
In the paper, the researchers state: “Our results demonstrated that the anabolic action of animal vs. vegan dietary patterns are similar.” This finding directly contradicts long-held beliefs about animal protein superiority.
Animal protein vs Plant protein for muscle-building
It’s been a heavyweight debate for years now, but the latest research shows animal protein is no better than plant-based protein when it comes to building muscle. (Graphic by Michael B. Vincent)
Protein Timing Myth Busted
The researchers also tested whether protein distribution evenly throughout the day matters. Half the participants in each diet group consumed their protein in three uneven meals (10%, 30%, and 60% of daily protein), while the other half spread their protein intake evenly across five meals (20% each).
Despite popular theories suggesting that even protein distribution is optimal, the study found no significant difference between these approaches.
“There was no effect of dietary pattern or protein distribution on the stimulation of myofibrillar protein synthesis rates,” the researchers reported. Simply put, whether participants ate animal or plant proteins, and regardless of how they timed their meals, their muscles synthesized new proteins at similar rates.
The data rebuts theories suggesting precise meal timing and protein distribution are critical for muscle development. Exercise appears to enhance the body’s ability to use both protein types effectively, minimizing differences between animal and plant sources.
Mental and Physical Benefits
Interestingly, the study uncovered psychological differences between the diet groups. Participants following omnivorous diets reported “greater feelings of pleasantness” compared to those on vegan diets. However, the vegan group reported “higher feelings of energy and lower feelings of tiredness.” This suggests that while vegan diets may support equal muscle growth, they might also offer some advantages for energy levels during training.
The findings come at a time when plant-based eating continues to gain popularity, with many people reducing animal product consumption for health, environmental, or ethical reasons. This research provides reassurance that those choosing plant-based diets can achieve their fitness goals without compromise.
For athletes, fitness enthusiasts, and anyone concerned about maintaining muscle mass while reducing animal product consumption, the implications are straightforward: protein quality matters less than overall diet quality and consistent resistance training. You can build muscle effectively without animal products if you consume sufficient total protein from varied plant sources.
Paper Summary
Methodology
The researchers conducted a randomized controlled trial with 40 healthy, physically-active young adults (28 males, 12 females, average age 25 years). Participants were randomly assigned to one of four groups: omnivorous diet with balanced protein distribution (OMN-B), omnivorous diet with unbalanced protein distribution (OMN-UB), vegan diet with balanced protein distribution (VGN-B), or vegan diet with unbalanced distribution (VGN-UB). All participants consumed 1.1-1.2 g/kg/day of protein. The balanced distribution consisted of five meals with 20% of daily protein at each meal, while the unbalanced distribution had three meals with 10%, 30%, and 60% of daily protein. Participants completed a 9-day resistance training intervention with three supervised whole-body resistance exercise sessions. Researchers measured myofibrillar protein synthesis using deuterated water (D2O) consumption and muscle biopsies from the vastus lateralis (thigh muscle).
Results The study found no significant differences in myofibrillar protein synthesis rates between any of the groups. The rates were 3.04±1.85%/day for OMN-UB, 2.43±1.21%/day for OMN-B, 2.52±1.77%/day for VGN-UB, and 2.49±1.56%/day for VGN-B. This indicates that both vegan and omnivorous diets supported similar muscle protein synthesis when protein intake was matched. The protein distribution pattern (balanced vs. unbalanced) did not affect muscle protein synthesis rates either. The study also assessed psychological well-being and found that participants on omnivorous diets reported greater feelings of pleasantness, while those on vegan diets reported higher energy and lower tiredness.
Limitations
The study was conducted over a relatively short period (9 days), so long-term effects remain unknown. The sample size (10-11 participants per group) was relatively small. All participants were young (20-40 years) and healthy, so results may not apply to older adults or those with health conditions. The researchers note that resistance exercise may have enhanced the anabolic response to both dietary patterns, potentially eliminating subtle differences between animal and plant proteins that might exist in less active individuals.
Funding and Disclosures
The study was funded by The Beef Checkoff, which could potentially introduce bias since the organization represents beef producers. However, the researchers stated that “Beef Checkoff sponsor was only involved in financial support of the project, without involvement in design, data collection, and analysis, nor interpretation and dissemination of the report.”
Publication Information
The study “Impact of Vegan Diets on Resistance Exercise-Mediated Myofibrillar Protein Synthesis in Healthy Young Males and Females: A Randomized Controlled Trial”
was published in Medicine & Science in Sports & Exercise in March 2025 (accepted March 29, 2025).
The research was conducted by Andrew T. Askow, Takeshi M. Barnes, and colleagues from the Department of Health and Kinesiology and Division of Nutritional Sciences at the University of Illinois Urbana-Champaign. The study was registered with ClinicalTrials.gov (NCT04232254).
3 Then the king instructed Ashpenaz, the master of his eunuchs, to bring some of the children of Israel and some of the king’s descendants and some of the nobles, 4 young men in whom there was no blemish, but good-looking, gifted in all wisdom, possessing knowledge and quick to understand, who had ability to serve in the king’s palace, and whom they might teach the language and literature of the Chaldeans. 5 And the king appointed for them a daily provision of the king’s delicacies and of the wine which he drank, and three years of training for them, so that at the end of that time they might serve before the king. 6 Now from among those of the sons of Judah were Daniel, Hananiah, Mishael, and Azariah. 7 To them the chief of the eunuchs gave names: he gave Daniel the name Belteshazzar; to Hananiah, Shadrach; to Mishael, Meshach; and to Azariah, Abed-Nego.
8 But Daniel purposed in his heart that he would not defile himself with the portion of the king’s delicacies, nor with the wine which he drank; therefore he requested of the chief of the eunuchs that he might not defile himself. 9 Now God had brought Daniel into the favor and goodwill of the chief of the eunuchs. 10 And the chief of the eunuchs said to Daniel, “I fear my lord the king, who has appointed your food and drink. For why should he see your faces looking worse than the young men who are your age? Then you would endanger my head before the king.”
11 So Daniel said to the steward whom the chief of the eunuchs had set over Daniel, Hananiah, Mishael, and Azariah, 12 “Please test your servants for ten days, and let them give us vegetables to eat and water to drink. 13 Then let our appearance be examined before you, and the appearance of the young men who eat the portion of the king’s delicacies; and as you see fit, so deal with your servants.” 14 So he consented with them in this matter, and tested them ten days.
15 And at the end of ten days their features appeared better and fatter in flesh than all the young men who ate the portion of the king’s delicacies. 16 Thus the steward took away their portion of delicacies and the wine that they were to drink, and gave them vegetables.
17 As for these four young men, God gave them knowledge and skill in all literature and wisdom; and Daniel had understanding in all visions and dreams.
18 Now at the end of the days, when the king had said that they should be brought in, the chief of the eunuchs brought them in before Nebuchadnezzar. 19 Then the king interviewed them, and among them all none was found like Daniel, Hananiah, Mishael, and Azariah; therefore they served before the king. 20 And in all matters of wisdom and understanding about which the king examined them, he found them ten times better than all the magicians and astrologers who were in all his realm. 21 Thus Daniel continued until the first year of King Cyrus.
OTOH...the human body was designed to ingest and live on different and varied comestibles. You are arguing against that and so are WRONG!
Obviously and sadly, you do NOT "know the truth"; so stop claiming that you do.
For instance, there have been many cases where vegetarians and especially vegans have been taken to court, because they have children who are SO undernourished and ailing, DUE TO THEIR DIET, that it has been considered to be CHILD ABUSE!
Even back at the dawn of hominids, mankind was eating a variety of different things...not just a plant based diet. FR's archeological threads have great links to studies and videos on all kinds of stuff; do avail yourself of them, OR...do your own research.
I have an adult progeny who was a Phsycho-Bio major with a speciality in PRIMATOLOGY. And as still an undergrad, did the FIRST major study, EVER, on captive mandrills, AND delivered a lecture on it, FOR people already in that field. Do I know as much about this topic? HELL NO! But having conversations and proof reading the papers on this as well as the study done for the government of Barbados ( done in the field...studying WILD green monkeys ), and just having conversation about primates, I most probably know far MORE about this ( gorillas too! ) than you.
Just a word of advice...be careful, you never really know WHO you are posting to on FR, nor what someone may know, who DOES know far more than you do...and no, I talking about other posters, past and present, on this site; not me...right now.
What about all of the past studies, re people eating"THE MEDITERRANEAN DIET,the one where everyone ate tones if yogurt as well as everything else,or some Russian town ( okay that one was decades ago ), and on and on and on!
You were dead WRONG about gorillas, you are wrong about a LOT of things, but still you keep throwing in all kinds of other garbage.
Want to believe what YOU want, even when it's a load of tripe. Fine......do so, but please think more than twice about coming back and replying to me, because your abject lack of factual knowledge, is NOT going to help you one bit. And frankly, it's no skin off my nose!
THERE ARE NONE SO BLIND AS THOSE WHO WILL NOT SEE, which is where YOU are stuck in right now. Pity that...........
A 9-day study with 40 subjects split into 4 groups? Not good science?
Here’s a conclusion for you: Just feed ‘em zee bugs!
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