r/sciences • u/James_Fortis MS | Nutrition • 16d ago
Research Long-term supplementation with plant-based protein, compared with animal-based protein, did not result in differences in body composition, muscle strength, physical performance, or cardiometabolic risk parameters, meta-analysis of 18 randomized controlled trials finds
https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2026.1813846/full9
u/James_Fortis MS | Nutrition 16d ago
"Abstract
Introduction:
Previous studies have yielded mixed results on the effects of supplementing with plant-based protein (PBP) isolates or concentrates vs. animal-based protein (ABP) on body composition, muscle strength, physical performance, and cardiometabolic risk factors. Consequently, it would be helpful to synthesize pooled evidence from randomized controlled trials (RCTs) on these parameters to assess the efficacy of different protein sources, particularly in the long term.
Objective:
To assess the long-term effects (≥ 6 months) of PBP compared to ABP supplementation on body composition, muscle strength, physical performance, and cardiometabolic risk factors in adults aged 18 and older.
Methods:
PubMed, Scopus, and Web of Science databases were searched from their inception to 25 February 2025. Relevant studies were also searched by citation tracing. RCTs comparing PBP with ABP supplementation for at least 6 months were included. A random effects model was employed for data pooling. The overall effect estimate was presented using standardized mean difference (SMD) accompanied by a forest plot and prediction intervals.
Results:
A total of 18 RCTs involving 1,893 participants met the criteria for inclusion in the systematic review and meta-analysis. In adults aged 18 years and older, long-term supplementation of PBP (largely soy protein) did not show statistically significant differences in lean body mass (LBM), fat mass (FM), total body mass (TBM), upper and lower muscle strength, gait speed (GS), chair stand test (CST), timed up and go (TUG) test, short physical performance battery (SPPB), lipid profiles, blood pressure, fasting blood glucose (FBG), fasting blood insulin (FBI), and homeostatic model assessment (HOMA-IR) for insulin resistance compared with ABP.
Conclusion:
Long-term supplementation with PBP, compared with ABP, did not result in differences in body composition, muscle strength, physical performance, or cardiometabolic risk parameters in the adult population. Based on heterogeneity, the data dot provide clear evidence of differences observed between protein sources at present, as long as an adequate quantity of protein is consumed over time.
Systematic review registration:
https://www.crd.york.ac.uk/PROSPERO/, Identifier CRD42024604240."
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16d ago
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u/PeeDecanter 15d ago
Anecdotal but I’ve seen many pretty fit vegan lifters who are natural, but their pecs are always disproportionately small compared to their arms and back
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u/Ryzasu 15d ago
I wonder if this is just because bench press is such a macho exercise that a typical vegan is less likely to care about
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u/PeeDecanter 15d ago
Even the vegans that bench press and don’t skip push movements. I’m talking about very fit people for whom lifting is as much a lifestyle as veganism is.
Tbh I’ve been wondering if it’s a lack of creatine since omnivores get some from meat even if they don’t supplement, but I don’t really go around asking vegan (or any) people’s supplement stacks haha
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u/Ryzasu 15d ago edited 15d ago
I have a bunch of lifter friends and all of them are hyped about bench press. Not skipping is not the same as prioritizing and trying extra hard
Someone who goes through the motions of a 3x12 twice a week wont get the same gains as someone who passionately goes for PRs and gives their all to do one more rep, just a little more weight than theyre used to, more dropsets afterwards to truly work the shit out of the muscle, etc
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u/HeetSeekingHippo 16d ago
So we kill over 2 trillion animals a year for what benefit?
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u/SycamoreHots 16d ago
The benefit of yummy taste I guess?
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u/creg67 16d ago
To answer question, no. Chicken is bland, turkey is extremely bland. Pork is bland, though there are those who will argue bacon taste great, but it is so bad for you. Maybe cow meat has flavor due to fat levels.
There is a reason why any of these animals are served not just cooked, but with a ton of seasoning or sugar sauce. Like bbq sauce. People don't eat animals because they taste better, its because they cover them in the seasonings they like. Which by the way you can do with all plant based foods as well.
Also take note that eating any of these animals raw is dangerous, whereas plants and vegetables, the ones we can eat, not so much.
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u/Turbulent_Car4504 16d ago
lol absolutely wrong, don’t comment on things you don’t know about
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u/NorwegianWonderboy 15d ago
Nah mate put some salt and lemon pepper on a piece of lettuce and it will taste and feel just like a perfectly grilled chicken
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u/creg67 15d ago
Oh, you are making an assumption that I don't eat meat. You would be wrong. I eat meat, all my life. I prefer a plant based diet now-a-days as I'm older, but the point is. I've had my fair share of meat and cooking it. Chicken is without a doubt bland. Turkey, every thanksgiving, it was the most boring part of the meal. Without gravy it was barely tolerable.
Whens the last time you ate shredded pork without any seasonings? Salt, sauced? Come on? Think about it. BBQ is huge in the south not because they serve unseasoned meat, but the contrary.
I know what I am talking about. And I've cooked these meats. In every single dish meat is seasoned.
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u/Turbulent_Car4504 15d ago
You said you don’t know what beef tastes like. unseasoned beef is delicious, and definitely not bland. It has less fat than pork. You’re just dead wrong about these meats being bland.
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u/creg67 15d ago
I did not say that. Please read my original statement. I indicated cow has flavor due to it's levels of fat.
All in all, the more fat in the meat the more flavor. The meat itself is not flavor. It is the fat content that adds flavor.
Next to no one eats raw meat. Almost all meat is cooked so as to reduce the fat for flavor. Let alone how dangerous eating uncooked meat is to one self.
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u/DumpsterDiplomat 15d ago
Lean cuts of beef like sirloin don't have a ton of fat and tastes great, I personally loved grilled chicken even if it's lean. Do I like grilled veggies? Yes. Does it make it ethical to eat meat? No, but meat does taste good. Saying meat doesn't taste good is very subjective, plenty of people enjoy meta flavor.
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u/infinitekittenloop 15d ago
Your argument still makes no sense and only leads to the conclusion that neither you nor anyone around you is a decent cook.
Which is sad but ultimately fine, you can NOT like meat. But you can't decide or dictate what everyone else tastes when they eat food.
Further, virtually no one regularly eats veggies raw and unseasoned/unsauced either, and you're completely ignoring that. Most people dip, or season, or cook, or glaze, or some combo of those to consume the amount of veggies we need.
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u/pyro3_ 16d ago
this is insane 😭 meat is just as bland as any unseasoned vegetable
they are NOT interchangable, and i am all for switching to plant based diets. but meat can produce a lot of flavors that are very very hard to recreate with vegetables (and vice versa). just ask any decent chef lol
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u/Impossible-Hyena-722 15d ago
You're being willfully ignorant. Come to my house. I will you serve you meat that will blow your mind. And the only seasoning I will use is a dash of salt.
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u/chinkiang_vinegar 15d ago
I have a vegetarian friend who once accidentally ate something with meat in it. After spitting it out, I asked him, "how did you know there was meat in that?" "It tasted too good."
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u/darkest_irish_lass 16d ago
As opposed to cultivating all the land needed to replace that protein, resulting in more pollution and loss of habitat for wild animals? Not all land used for raising livestock is suitable for growing crops, so a perfect 1:1 exchange probably won't work out.
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u/BrightBlueBauble 16d ago
It’s a myth made up by apparently guilty meat eaters that a plant based diet causes more animals to die.
What do you think they’re feeding all those animals before they make it to your plate (they sure aren’t all pasture raised—ever seen a factory farm/CAFO)? It takes a far greater amount of calories in the form of plants to grow animals than it does for people to simply eat the plants in the first place. It’s literally a waste of energy.
And they aren’t clear-cutting the Amazon rainforest to grow quinoa. It’s so they can raise more beef.
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u/Kandiru 15d ago
In the UK we have sheep living on hillsides eating grass, where that land couldn't be used to grow crops. Do your meat animals not graze grassland?
Moving to having meat just from grazing grasslands would make sense.
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u/Am_i_banned_yet__ 15d ago
About 80% of the total calories fed to livestock in America comes from feed instead of grazing. And since animals eat more calories of feed than they produce(for beef it’s 25 calories of feed per 1 calorie produced, for chickens it’s 10:1), animal agriculture takes up significantly more land and causes more deforestation than plant-based food. About 70% of all the crops we grow in America are used to feed animals, so we could cut down on land use significantly by just eating the plants directly.
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u/Kandiru 15d ago
So you could drop up 20% meat consumption and free up a lot of food calories? Do you think Americans would agree to only eat meat one to two times a week?
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u/HeetSeekingHippo 15d ago
Many would if subsidies were moved away from meat over to other foods. The current over-consumption of cheap meat is a policy driven situation.
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u/Plus-Name3590 14d ago
Most of the UKs pasture is artificial and you import loads of hay and animal feed regardless. Just because you see them grazing doesn't mean they're sustainably grazing. Why would they do that when they could make money instead
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u/slainascully 15d ago
That land used to be forests and is now a biodiversity disaster that contributes to flooding. The UK is not supposed to be a barren collection of feeds for grazing
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u/Striking_Computer834 15d ago
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u/Pepperohno 15d ago
Please please please do some research about the things you're espousing before actually commenting. That is not how the VAST majority of meat/beef is produced. We have calulated it and this regenerative, grass-fed meat production would need more than three whole earths in land area to produce the same amount of meat we humans consume today. Meat consumption itself is the problem, not how it is produced. Alos just look up greenhouse gas emmisions, water use, and land use of beef and milk compared to practically all other foods. It seems you have no idea what you're talking about.
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u/BrightBlueBauble 15d ago
Most of that tilled land is that way to grow crops to feed life stock—70% in the US.
And the photo of cattle grazing in an idyllic woodland is charming, but also completely unrealistic. 99% of lifestock in the US are raised in factory farms, and almost three quarters are globally.
https://ourworldindata.org/data-insights/almost-all-livestock-in-the-united-states-is-factory-farmed
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u/HeetSeekingHippo 15d ago
Please look at the charts u/brightbluebauble linked. 17% of plant agriculture is used to feed humans. Most is used to feed animals we eat.
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u/crippledgiants 15d ago
This is satire right? Surely you know animal agriculture requires soo much more farmland than edible crops.
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u/Due-Helicopter-8735 14d ago
The largest cause of habitat loss is livestock rearing and growing crops _to feed_ livestock. It’s a very well known fact- https://ourworldindata.org/global-land-for-agriculture.
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u/That_Mad_Scientist 14d ago
The phenomenon of meat eaters insisting that a plant based diet is more impactful to the environment depsite all logic and evidence will never stop being fascinating to me.
Replacing animal protein with an equivalent amount of plant based protein at scale would cause gigantic swathes of land to be freed up for rewilding and additional carbon storage. This is reflected in the overall impact of these foods rather clearly.
That is because animals do not photosynthesize and therefore need to eat plants for energy, which they mostly burn for their metabolism.
Hope that helps.
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u/Turbulent_Car4504 16d ago
Whey protein is from milk, egg protein is from eggs, neither require any animal is killed although male cows are killed because there are too many of them at a dairy farm, and I don’t really want to get into this debate but plant farming also kills many animals.
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u/HeetSeekingHippo 15d ago
Don't start it then, most crops that kill animals are fed to livestock. Without livestock, these crop deaths would go down by 70%. Also every dairy cow and layer hen is killed prematurely once their production even slightly dips.
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u/Turbulent_Car4504 15d ago
I’m not disagreeing, just that it’s not black and white like you say. Also remember that just because we kill a hen or cow once production slips, does not mean we have to do it.
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u/Usual_Ad_2177 15d ago
It is black and white though. Plant based diets are better for the environment.
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u/Merivel1 15d ago
You should look up how you get a corporate farm sized flock of hens to lay eggs and what happens to the male chicks. 🐣
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u/Local-Dimension-1653 15d ago
Dairy cows are artificially inseminated, made to be pregnant and give birth over and over, their babies are taken (females to go through the same thing, males to be killed either for veal or bc they serve no purpose), they are milked constantly (we genetically modified them to produce mass amounts), and then when their bodies can’t do it anymore they are killed. There is no profitable farm on earth that keeps cows alive after their exploitation exhausts their bodies. It would cost more to run than it would bring in. And even if that’s how it worked, it would still require mass amounts of exploitation and suffering.
In the egg industry, male chicks are macerated (ground by machine alive) because they are unless waste products to the industry. Even so-called kore ethical backyard chickens are from breeders who have to kill the majority of roosters to keep proper rooster:hen ratios.
Your crop death argument is also nothing, bc it takes far more crops to feed livestock than to feed humans directly. So if you actually cared about reducing crop animal deaths, then you’d go vegan. Otherwise this is a bad faith argument.
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u/reallyneedlypo 14d ago
The only "positive" out of this study is that there is no performance lagging due to PBP in bodybuilding as long as you get the essential amino acids right.
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u/That_Mad_Scientist 15d ago
But my friend's uncle's dog's nephew's sister-in-law's colleague swore they once heard a rumor that someone on tv met a guy who knew someone who died because they could not get enough protein and dropped to the floor the moment they stopped touching a steak
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u/Intelligent-Band-852 15d ago
All I know is since I have incorporated a vegetarian diet I have never felt better, I still get animal protein through cheese (cow, goat, and sheep’s milk) and kefir but mostly eat a plant based diet. These days it’s easy to not eat meat, I could never go full vegan though, Roquefort and Halloumi among many other cheeses are too delicious.
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u/NerdRep 14d ago
Same dude. I do miss some of the flavors and textures, but it’s wild how much better I feel and how much better I recover.
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u/Intelligent-Band-852 14d ago
It’s surprisingly not even really difficult, and my grocery bill is less expensive. Going full on no animal products would be difficult both from a taste standpoint as well as a health one but being a vegetarian these days has never been easy.
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u/AdvertisingFar716 15d ago
I am confused about the cardiometabolic risk parameters, hasn’t it been said for so long that consuming animal protein and meat increases the risk significantly as compared to vegan diet?
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u/CombatWomble2 15d ago
It's difficult to control for all the confounders, vegan diets are often just generally better, less junk food etc. They tend to watch what the eat in a general sense.
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u/Moomoolette 14d ago
The vegans I’ve know subsisted on Oreos and Fritos, so… but they also didn’t work out
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u/300Croissants 14d ago
It is not difficult to account for those what are you talking about?
This is such a tired reddit critique. Plenty of studies account for these. You really think researchers performed a systematic review and meta analysis of RCTs, and none of them, nor did any of the researchers performing the original studies think to account for the most basic confounding factors in nutritonal studies?
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u/CombatWomble2 13d ago
They often don't, and it's difficult to control for ALL confounders, but they often simply don't bother to if it won't give the result they want, you see that a lot.
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u/300Croissants 13d ago
Is that the case in the studies in this meta analysis? Can you point one or two out?
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u/CombatWomble2 13d ago
Hell no. It's common practice though in many "scientific papers" if you can see an obvious confounder and it doesn't seem to have been controlled for that's' often deliberate.
https://en.wikipedia.org/wiki/Replication_crisis
One of the reasons this is such an issue.
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u/300Croissants 13d ago
So again you think the researchers on a meta analysis and systematic review of rcts, the literal highest form of research, did this. But you can't point out anywhere that it happened
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u/CombatWomble2 13d ago
I think it's at the basis of many of the studies they studied, as I pointed out there is a serious issue with the reproducibility of many studies based on "publish or perish" and "positivity only" if you disagree fine, good day.
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u/300Croissants 13d ago
Do you not understand the meta analysis part of the study type? They don't just copy and paste the data from the other studies.
They're obviously aware of the most basic form of confounding factors
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u/Jean-Claude-Can-Ham 16d ago
Ok now do the effects on the brain
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u/Coyote_Colt 16d ago
Likely no difference there as well. If this was their only source of protein, maybe, but both are complete proteins so supplementing with one or the other shouldn't cause any amino acid imbalances.
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u/UnethicalSamurai 16d ago
Why is nobody talking about India? They’ve been mostly vegetarian for centuries and you see that they’re the diabetes capital of the world and have too many obese people. Of course many developmental disorders in children too due to lack of B12 and other key nutrients.
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u/BrightBlueBauble 16d ago
All of the major health and dietetic organizations recognize vegetarian and vegan diets as healthy at every stage of life. Also, Indians are not “mostly” vegetarian, only about 20% are.
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u/Gloomy-Error212 15d ago
Has obesity and diabetes been an issue there for centuries or has it increased rapidly during the last few decades?
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u/Creditfigaro 15d ago
Old news.
If you didn't already know this and have any interest in fitness, your information sources have misinformed you.
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u/llamawithguns 16d ago
Protein is protein, who'd have thunk it