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).
vegan - old injun word - mean lousy hunter - ugh
Cut out wheat or anything associated with grains, rye, oats, corn, rice etc. and THEIR OILS..
High proteins and FATS are a necessity!.................
Cows get huge. They have 4 stomachs...........We are not cows.
“omnivorous dieters reported greater meal satisfaction [than vegans]”
Yeah, but those omnivorous eaters don’t get the Holier Than Thou satisfaction of telling others about the Vegan Good News.
Y’all go on eating your Kale and sprouts.
I enjoy my fried chicken, Brochili and mashed potatoes.
plus gravy and butter!
I call BS!
Bkmk
Cat food has a lot of Taurine in it.
Did you give your Dad energy drinks or another source for taurine?
Was Thoreau the original chinbeard soy boy?
ha ha, maybe do this diet for a year and see what happens.
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.”
It is vital to life for them.
Mostly taurine is found in heart meat but how many people eat heart any more?
You may find chicken livers but finding chicken hearts is not so common. And certainly beef and pig hearts are even more uncommon to find on the menu.
Heart meat used to be reserved for the hunter because it was thought that it would make them strong.
Maybe our ancestors were on to something.
Or on something. That could be it too.
You pretty much have to have your butcher order it special and youre likely going to have to take the whole box (50lbs).
Historically they werent worth much here so they started sending them to Japan because they are worth a lot more to the purveyors of yakitori.
I mainly just wanted to show that this argument has been going on for at least 171 years (Walden was published in 1854.).
Plato advocated avoiding consuming animal products, so make that 2,500 years.
Getting the 70-90 grams of protein my doc wants me to consume is hard enough...can’t imagine how much veggie protein I would have to eat to do so.
If it’s so great, why do they always look malnourished and act angry?
CC
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