Protein-Maxxing: Is It Actually Bad For Us?

Protein is everywhere — tons of us are trying to cram more of it into our diets, and it's showing up in our lattes, our snack bars, even our popcorn. But just as we’re getting on board with protein-maxxing, a bunch of headlines have started saying the opposite: that eating LESS protein could actually help you live longer. So what's going on here?? Should we be piling on the protein — or pulling back? And could going too low actually be dangerous? We talk to biologist Prof. Dudley Lamming and exercise physiologist Prof. Stuart Phillips to find out. Note: This episode mentions calorie restriction. Please take care when listening, and here are some resources: National Association of Anorexia Nervosa and Associated Disorders (ANAD) helpline: 1(888)-375-7767 Crisis support: United States: US National Suicide Prevention Lifeline Dial 988 (Online chat available); https://www.crisistextline.org/text-us/ Text “HOME” to 741741 Australia: Lifeline 13 11 14 (Online chat available) Canada: Call or text 988 United Kingdom: Samaritans 116 123 (UK and ROI) Full list of international hotlines here Other help available: spotify.com/resources Find our transcript here: https://tinyurl.com/ScienceVsProteinMaxxing In this episode, we cover: (00:00) Protein-Maxxing or Protein-Minning? (02:15) Restricting Protein Makes You Live Longer??!? (09:20) A Tale of Brown Fat and mTOR (13:45) What Could Go Wrong? (21:20) So What the Hell Should We Be Eating? This episode was produced by Rose Rimler, with help from Meryl Horn, Michelle Dang, and Ekedi Fausther-Keeys. We’re edited by Blythe Terrell. Wendy Zukerman is our executive producer. Fact checking by Marlowe Starling. Video editing and sound by Bobby Lord. Music written by Bumi Hidaka, Peter Leonard, Emma Munger and Bobby Lord. Thanks to the researchers we spoke to for this episode including Prof. Edward Giovannucci, Prof. Holly Brown-Borg, Prof. John Speakman, Dr. Mingyang Song, and Dr. Jessica Biesiekierski. And thanks as well to Humdinger Studios in Melbourne and Wolff Island Studios in New York City. Science Vs is a Spotify Studios Original. Listen for free on Spotify or wherever you get your podcasts. Learn more about your ad choices. Visit podcastchoices.com/adchoices

• 0:00Speaker 00

  I have a confession to make. I, um, I am

• 0:09Speaker 00

  Whoa, I would never have thought I'd see the day. Hi, I'm Wendy Zukerman and this is Science Versus.

• 0:23Speaker 00

  These days, protein is everywhere. It's being added to all kinds of foods, from lattes to popcorn. Cottage cheese is flying off the shelves and people are telling pollsters, "Yes, I am actively trying to get more protein into my diet." And some of us are going hard. They are protein-maxing. High-protein talkers. High-protein enchilada pasta. Five reasons why protein is essential and why I need more of it.

• 0:51Speaker 01

  It helps us build muscle, helps to control our hunger, helps to maintain a lean physique, and makes us look sexy as

• 0:58Speaker 02

  High-protein, low-calorie beef teriyaki summer rolls.

• 1:03Speaker 03

  We still need more protein.

• 1:07Speaker 00

  But just recently, we've been hearing something that is turning all of this on its head, that suggests we are doing protein all wrong. Headlines are saying that we need to actually cut back on protein if we want to live long and healthy lives. New research is challenging the high-protein craze.

• 1:26Speaker 04

  Decades of data, animal studies and human studies, asking the question whether eating less protein can promote healthier aging and help to extend your lifespan. Low-protein diets actually help you live longer.

• 1:38Speaker 00

  So what is going on here? Should we be protein-maxing or protein-mining? When it comes to protein, there's a lot of

• 1:46Speaker 03

  We still need more protein.

• 1:49Speaker 00

  But then, there's science.

• 1:55Speaker 00

  And if you have a friend who is guzzling down protein or just confused about, "What's the right thing to do here?", understandably, share them this episode where on YouTube or wherever you get your podcasts.

• 2:13Speaker 05

  Are you looking for support in your weight management journey? Zepbound terzepatide may be able to help. Zepbound is a prescription medicine used with a reduced-calorie diet and increased physical activity to help adults with obesity or some adults with overweight who also have weight-related medical problems to lose excess body weight and keep the weight off. Zepbound is approved as a 2.5, 5, 7.5, 10, 12.5, or 15-milligram injection. Zepbound contains terzepatide and should not be used with other terzepatide-containing products or any GLP-1 receptor agonist medicines. It is not known if Zepbound is safe and effective for use in children. Don't share needles or pens or reuse needles. Don't take if allergic to it.

• 2:56Speaker 05

  Or if you or someone in your family had medullary thyroid cancer or if you've had multiple endocrine neoplasia syndrome type 2, tell your doctor if you get a lump or swelling in your neck. Stop Zepbound and call your doctor if you have severe stomach pain or a serious allergic reaction. Severe side effects may include inflamed pancreas or gallbladder problems. Tell your doctor if you experience vision changes before scheduled procedures with anesthesia. If you're nursing, pregnant, plan to be, or taking birth control pills. Taking Zepbound with a sulfonylurea or insulin may cause low blood sugar. Side effects include nausea, diarrhea, and vomiting, which can cause dehydration and worsen kidney problems. Talk to your doctor. Call 1-800-545-5979 or visit zepbound.lily.com.

• 3:44Speaker 05

  This episode is brought to you by Born in Roma Fragrances by Valentino Beauty, the iconic fragrance duo. Donna Born in Roma Eau de Parfum is a feminine fragrance featuring juicy black currant, central jasmine, woody cashmerin, and warm vanilla. Its masculine counterpart, Womo Born in Roma Eau de Toilette, has notes of fresh violet leaf, aromatic sage, green vetiver, spicy ginger, and mineral salt. Shop at macy's.com.

• 4:21Speaker 00

  Welcome back. Today, we are digging into the science on protein. And who else to give us that science but meathead senior producer, Rose Rimble?

• 4:32Speaker 02

  Hi, Wendy.

• 4:33Speaker 00

  Hello. I have a confession to make.

• 4:37Speaker 02

  You're protein-maxing right now as we speak somehow?

• 4:41Speaker 00

  I, um, I am adding protein powder to my yogurt.

• 4:47Speaker 02

  Whoa, I would never have thought I'd see the day.

• 4:51Speaker 00

  Trying to build more muscle and I got, I got sucked in. But now these headlines say, "Stop doing that."

• 5:03Speaker 00

  Rose, I'm being vulnerable with you now.

• 5:06Speaker 02

  Wow, I can't believe you'd share something so personal.

• 5:10Speaker 02

  Thank you, I really appreciate that. You're not alone, like, that's not really that special of a confession. I think a lot of people are doing that, which is why, you know, it was very surprising to, you know, crack open the internet one day and see that now everybody's talking about, "Maybe we should be doing less with protein instead of more."

• 5:31Speaker 00

  Yes, yeah. I was so surprised when I'm getting these videos saying, "New study finds protein restriction is the way to go." So is the protein pendulum swinging?

• 5:44Speaker 02

  That's the question. And a lot of the headlines that are talking about this are referring to this one new paper that came out recently. It's all about protein and lifespan. And I talked to one of the authors, his name is Dudley Lamming.

• 5:58Speaker 06

  I'm a professor of medicine at the University of Wisconsin-Madison, and I'm an aging biologist.

• 6:04Speaker 02

  Not as in the creaks and pains of old age are catching up with him?

• 6:09Speaker 00

  Yeah, I'm an aging podcaster.

• 6:13Speaker 02

  You study aging?

• 6:15Speaker 06

  I've been studying aging for about 20, 25 years now.

• 6:20Speaker 00

  This is exciting, though, because he is patient zero. He's the author that launched a thousand headlines about how protein restriction is healthy.

• 6:31Speaker 02

  Yeah, I mean, kind of accidentally. I mean, that wasn't Dudley's intention when he wrote the paper.

• 6:37Speaker 06

  I was quite surprised. You know, it was originally written as an article, you know, for scientists by scientists. And so it was really interesting that it got so much attention.

• 6:47Speaker 02

  Because it turns out that scientists like Dudley have actually been studying protein restriction for a long time. I had never heard of it, but I was in the dark. This has been around for a while. And actually, where this all comes from is, you know how there are studies in animals that find that calorie restriction can extend lifespan?

• 7:07Speaker 00

  Yes, yes, of course. This is fasting, people might, fasting diets that are also very popular right now. That, all that research started off with animals. It's exciting, weird studies in animals, little, the little animals, the worms, the flies, they would put the board fasting diets and realize, "What, they were living longer?"

• 7:24Speaker 02

  Yeah.

• 7:25Speaker 00

  So they have basically been doing the same thing with protein restriction all this time, scientists?

• 7:32Speaker 02

  More or less, yeah, because fasting or calorie restriction is pretty hard to stick to. So the idea here is like, well, actually, if we're seeing some of the same benefits from not reducing your overall energy intake, but just tweaking your macros so you eat less protein, then maybe this would be a lot easier for people to actually stick to.

• 7:50Speaker 00

  And do they find that, that in animals, if you restrict protein, they live longer?

• 7:58Speaker 02

  Yeah. Short answer, yeah. I mean, in a lot of organisms, mice and rats primarily, but they've also tested it in fruit flies and yeast.

• 8:07Speaker 00

  I don't know why you looked at me like that and said yeast. Do you know something I don't know?

• 8:12Speaker 02

  I'm just really trying to avoid saying animals like yeast, because it's not an animal.

• 8:17Speaker 00

  Because it's not an animal, what is it?

• 8:19Speaker 02

  It's a fungus.

• 8:20Speaker 00

  It's a fungus.

• 8:22Speaker 02

  And in these experiments, what scientists are doing is they, they're typically cutting the protein in the diets of these creatures, like, in half, and then increasing either the fats or the carbs, so that overall they're eating the same number of calories.

• 8:35Speaker 00

  Okay.

• 8:36Speaker 02

  And in mice, Dudley says that they live

• 8:40Speaker 06

  Up to 30% longer on a protein-restricted diet. And depending on exactly the conditions, it can be anywhere from 10% to 30%.

• 8:49Speaker 02

  You can see why that's exciting, because if that translated perfectly to humans, that would be an extra like 20 years on our lifespan.

• 8:56Speaker 00

  Yeah, yeah, for sure, if that translated to humans.

• 9:02Speaker 02

  Right. And so, back to this big study that got everyone all Twitter. It's not a new experiment that Dudley published, it's a review paper.

• 9:13Speaker 00

  Do you know, I still, Rose, after all these years, I still, I see the headline, "New study shows protein restriction helps you live longer." And in my head, I'm like, "Wow, they did a study in 40,000 people and they followed them and they found that those who didn't eat a lot of protein lived longer." And every freaking time you go to the paper, it's either a review paper looking at old studies or it's some research in rats.

• 9:44Speaker 02

  Yeah, you sweet summer child, when will you learn?

• 9:49Speaker 00

  But in some ways, um, depending on the review paper, this might be even more exciting, right? Because they're pooling together all of this research that we have from the past.

• 9:59Speaker 02

  Yeah.

• 10:00Speaker 00

  We're talking about a collector body of work.

• 10:02Speaker 02

  Mm hmm.

• 10:03Speaker 00

  But depends any of the bodies in this study, humans?

• 10:06Speaker 02

  There are some human bodies in this review paper.

• 10:09Speaker 00

  Okay.

• 10:09Speaker 02

  Um, obviously, there are no studies where scientists took, you know, a hundred human babies, randomized them to either low protein or more protein, and then followed them for a hundred years and saw which baby lived longer, right?

• 10:23Speaker 00

  Uh huh, yeah.

• 10:24Speaker 02

  But we do have studies where they put people on low protein diets for kind of a few weeks to a few months and seeing what happens to them. They they can measure certain things about them. So one that Dudley did, um, they got about forty people. All these were all men. They were overweight. Um, these guys were randomized to either go on a low protein diet or stay on their typical diet, which was high in protein.

• 10:49Speaker 00

  Uh huh.

• 10:50Speaker 02

  The guys in the control arm, they, you know, live life as usual, while the guys in the low protein arm.

• 10:56Speaker 06

  We found that they lost about a pound and a half a week and their blood glucose went down by about five percent.

• 11:04Speaker 00

  Were they, the two groups eating the same amount of calories? It's just that the protein restriction group ate less protein?

• 11:11Speaker 02

  No, here's the crazy thing. They were actually eating more calories than they had been before, and they still lost weight.

• 11:19Speaker 00

  So what is Dudley think is happening here?

• 11:22Speaker 02

  Okay, so here's what we know. We know that when you feed people a low protein diet, they make more of this particular hormone. And that hormone seems to have something to do with brown fat. Are you familiar with brown fat?

• 11:39Speaker 00

  Ah, there's two different cut, there's white fat, there's brown fat. Tell me more. What, why do we care about brown fat?

• 11:47Speaker 02

  So brown fat is when you end up with a lot more mitochondria in your fat. Mitochondria are.

• 11:54Speaker 00

  Powerhouse of the cell. They create ATP, fuel, energy for the body to use. Yeah, so what does that mean for this brown fat if it's got more mitochondria in it?

• 12:04Speaker 02

  Well, if your white fat starts recruiting more mitochondria, which are a little bit brown in color, that turns the fat from white to brown in a process that scientists very cleverly call beijing.

• 12:18Speaker 06

  Causing them to essentially start producing more energy in the form of heat. And so the mice literally burn off additional calories as fuel and overall lose weight.

• 12:31Speaker 00

  Oh, okay, so you restrict protein in your diet, or the mice restrict protein in their diet. They produce a hormone.

• 12:40Speaker 02

  Mm hmm.

• 12:40Speaker 00

  And what's this hormone called?

• 12:42Speaker 02

  Uh, it's called FGF twenty one.

• 12:45Speaker 00

  FGF, okay, I understand why you didn't, uh, I didn't name check it.

• 12:49Speaker 02

  It's not one of the cool hormones.

• 12:51Speaker 00

  No, but it is cool because, so to summarize, what Dudley thinks is happening, what, one of the reasons why he thinks protein restriction might be healthy is because when you restrict how much protein you eat, or when they do it with mice in a lab, you see an increase in that hormone. And then that starts recruiting mitochondria into your white fat, turning it into brown fat, and that increases the amount of energy in that fat, increasing the amount of heat, ultimately increasing the metabolism.

• 13:29Speaker 02

  That's what we think. I mean, not all of those steps have been shown in humans.

• 13:33Speaker 00

  Mm hmm.

• 13:34Speaker 02

  But I will say, I will say, there's still more reason to be excited about protein restriction.

• 13:39Speaker 00

  Mm hmm.

• 13:40Speaker 02

  There's this whole other thing that has to do with mTOR. Do you, you know what mTOR is? Are you familiar with that?

• 13:46Speaker 00

  Yes, this is, uh, big in the longevity community.

• 13:50Speaker 02

  Yep, they're always trying to hack mTOR.

• 13:52Speaker 00

  Yeah.

• 13:54Speaker 00

  Just, yeah, so walk us through, what's, tell us, what's mTOR?

• 13:58Speaker 02

  mTOR is an enzyme that coordinates cell metabolism. And the thing about mTOR is that it's kind of like a switch. When it's on, it tells cells to grow, and that seems to be linked to aging. And when it's off, it seems to increase what's called autophagy. And, Mandy, you know, you know all about this, right? From an old episode.

• 14:22Speaker 00

  It's one of my favorite processes in the body. Um, and it is a way that your body replaces damaged cell parts. And what happens is that a cell will literally eat itself. That's what autophagy means.

• 14:36Speaker 02

  Uh huh.

• 14:37Speaker 00

  So to take this back to protein restriction, what are they finding? It boosts autophagy?

• 14:46Speaker 02

  It looks like protein restriction, at least in mice, tamp down mTOR, boosts autophagy.

• 14:54Speaker 00

  Mm hmm.

• 14:54Speaker 02

  Um, and that might be what's leading to this increased lifespan, at least in these animal studies.

• 15:03Speaker 00

  But then, I'm, it's something inside me that still can't believe that restricting your protein is a good idea because have I just been sold a lie? I mean, don't we need, we need protein, right? For muscles, for balance, it's super important.

• 15:18Speaker 02

  Yeah, not all scientists are hopping on board the protein restriction train. Um, and there actually could be a downside here. It could be dangerous to try to do protein minning. Coming up next.

• 15:39Speaker 07

  This episode is brought to you by Michelob Ultra. Good times mean competitions between you and your friends, like seeing who can throw some pigskin the farthest or rush the field the fastest. Winner gets an ultra. Because it's not just a superior light beer, it's also giving fans superior access to their favorite sporting events. Superior is worth playing for. Visit michelobultra.com/superioraccess to enter. Enjoy responsibly. Copyright twenty twenty six Anheuser Busch InBev Michelob Ultra Beer, St. Louis, Missouri.

• 16:08Speaker 08

  College football is back. So Hilton called to me, the superstition concierge, to make your fan rituals a reality. Need a room to match your lucky number? We got you. Want to make sure our team doesn't wash your lucky jersey? Oh, that smells lucky. Hilton's unmatched hospitality can keep up with any superstition, even a marching band wake up call at five fifty five and fifty five seconds. Hit it! When you need a team that will do whatever it takes on game day, it matters where you stay. Hilton, for the stay.

• 16:39Speaker 09

  When you need to build up your team to handle the growing chaos at work, use Indeed sponsored jobs. It gives your job post the boost it needs to be seen and helps reach people with the right skills, certifications, and more. Spend less time searching and more time actually interviewing candidates who check all your boxes. Listeners of this show will get a seventy five dollar sponsored job credit at indeed.com/podcast. That's indeed.com/podcast. Terms and conditions apply. Need a hiring hero? This is a job for Indeed sponsored jobs.

• 17:09Speaker 10

  Whenever fall comes back around, it always feels like a fresh start. This year, I've been layering in some styles from the new Lululemon fall drop because the weather is shifting and I find I have to be ready for the entire day and not just one part of it. Lululemon's fall line has some really versatile transitional pieces, so I can just wake up, throw on a matching set, add a jacket or a fleece, and head out, knowing that I'll feel comfortable enough to go wherever the day takes me. Check out the new fall arrivals in store and online now at lululemon.com.

• 17:47Speaker 00

  Welcome back. Today, we're talking all about protein. If you have a friend slamming down the protein day after day, maybe send them this episode. Rose Rimla, senior producer at Science Versus. You promised me some more science on this protein restriction, saying that perhaps it's not good and we can keep our protein powder. Where do we go from here?

• 18:13Speaker 02

  Okay, so this idea of getting really low protein is so different from what we've been hearing, that I had to talk to other scientists for other perspectives. The first person I thought of was Stuart Phillips. He is an exercise physiologist at McMaster University in Canada. Stuart is not on team protein maxing. So right off the bat, I'll tell you that. In fact, last year, he actually wrote a piece saying that this whole protein craze has gotten so out of hand. And he actually titled that piece, "Twenty twenty five was the year that protein jumped the shark", an expression that kind of got him roasted by his family.

• 18:51Speaker 11

  My son was like, what is this shark thing? And I was like, well, there's this guy, uh, his name is Arthur Fonzarelli, and he was the fawns, and he once jumped over a shark. And he was like, what are you talking about? Like, so what does that mean? I was like, well, it was where the show really went downhill. And he was like, that doesn't make any sense.

• 19:11Speaker 00

  But it's very prescient because in 2025, he predicts that protein is gonna, it's all gonna go downhill from there, much like Happy Days. And here we are in 2026, headline saying we've gone too far.

• 19:25Speaker 02

  Yeah.

• 19:25Speaker 00

  So is it, but he said he's not on team.

• 19:28Speaker 02

  He's not on team protein maxing, but he's not on team protein minning either. So even though he thinks we've gotten a little overboard with our protein, he doesn't like those headlines that came out recently about how we all need to cut back and restrict our protein.

• 19:43Speaker 00

  Okay, why not?

• 19:44Speaker 02

  Yeah, we ran some of those headlines by him. Surprising new study links low protein diets to healthy aging. Eating less protein could help you live longer. What do you think?

• 19:55Speaker 11

  Yeah. Well, all of the titles you read would have been reduced protein helps you live longer, comma, if you're a fruit fly or a mouse.

• 20:06Speaker 00

  But you did, there was some human studies, right? There's at least that one that you told me about.

• 20:11Speaker 02

  Yeah, I mean, Stuart's issue with that study was that it was short and not, you know, you can't really extrapolate from like a 12 week study to what's gonna happen over an entire lifetime.

• 20:22Speaker 11

  You know, 12 weeks out of a year that has 52 weeks out of a life that is 84 years, you know, you can do the percentage.

• 20:32Speaker 02

  Another problem with the study, the menus of the people, you know, in the study were pretty different. So on the protein restricted arm, they were eating like a Mediterranean style diet, lots of fish and leafy greens, whereas the other diet was like ribs and hot dogs and hamburgers. So there's a lot different about that diet than just the protein content.

• 20:53Speaker 00

  This is, and then that's they found all these benefits.

• 20:56Speaker 02

  Yeah, and the benefits aren't too surprising. The calorie thing and losing weight is surprising, but like the other stuff, like that it would be better for you in these other ways is not surprising.

• 21:05Speaker 00

  Given that they're eating a much healthier diet, even if you forget about how much protein they're eating, that's, that's a reason to be skeptical. Okay, so we don't have many human trials really putting this to the test. We don't have long-term studies, true for many things. Okay, but I guess you promised danger.

• 21:31Speaker 02

  Yeah.

• 21:32Speaker 00

  That's why we call you Rose Danger Rimmler.

• 21:35Speaker 02

  Well, one of the reasons that Stuart is as skeptical as he is is because there's reason to believe that going quite low in protein could be bad for you. Because as we age, we get worse and worse at incorporating the protein that we eat into our muscles and we lose muscle mass. And so for older people, and these are the people who are probably like thinking about like, how, oh, how can I extend my lifespan? They're the exact group of people who probably shouldn't be going low in protein.

• 22:03Speaker 11

  I think that those folks are in, or are going to be in trouble. So they will lose muscle, they will get weaker, their risk for frailty goes up. And that's where my mom is right now. So I care about my mom.

• 22:19Speaker 02

  If you cut down your protein and you're not getting enough to like replenish your muscles, you could end up with something that's called sarcopenia, which is like not having enough muscle mass and being really frail.

• 22:31Speaker 00

  So this is, this is what we've known for a while. Protein is important for building muscle, so you need to get enough of it.

• 22:38Speaker 02

  Yeah, and if you don't, I mean, the sarcopenia thing, it is a pretty big deal. Like, we know that people who have sarcopenia, they are more likely to have falls, they're less likely to be able to be independent, you know, like eat, get dressed, go to the bathroom by themselves, and they're more likely to die like four times more likely compared to people of their age who don't have sarcopenia, according to one review. And it's not only that, though. Like, there's this whole other thing we have to think about when it comes to low protein diets. It could really mess with your immune system. And this goes back to the whole mTOR thing we were talking about before. So, you know, the, the low protein diets seem to suppress mTOR. That also suppresses your immune system.

• 23:19Speaker 02

  And we know that because there is a drug that people will take, these longevity hackers called rapamycin.

• 23:27Speaker 00

  That's right, yes.

• 23:28Speaker 02

  That drug is actually, it's approved as an immunosuppressant. That's what it's actually for. And they give it to people who get organ transplants to tamp down their immune system. So that's a side effect that can happen if you're taking rapamycin. Maybe a side effect that could happen if you're going low protein and tamping down your mTOR. You might be also tamping it down so much that it messes with your immune system. And that wouldn't show up as much in the mice studies because the mice aren't really exposed to a lot of pathogens or in these like clean sterile cages and labs, right? But in the real world, we're out in society getting grubby. And we actually have some signals in other places too, that this could be a problem. So like, I found this very small, but very interesting study. They got 12 elderly women.

• 24:12Speaker 02

  Half of them were on a low protein diet, like really low, the other half more normal. And they did stuff to them, like they tested their immune response. They exposed them to certain antigens and then saw like how well their body kind of responded to it.

• 24:29Speaker 00

  Okay.

• 24:30Speaker 02

  Antigens like tetanus, streptococcus, diphtheria, tuberculosis.

• 24:35Speaker 00

  They weren't messing around. Right. So what happened?

• 24:39Speaker 02

  So the people on the low protein diet, they didn't mount as efficient or as good of an immune response as the people on the adequate protein diet.

• 24:48Speaker 11

  People that are on low protein intakes have lower levels of immune markers and immune function.

• 24:56Speaker 02

  And that's something that Stuart and Dudley agree on. Dudley being the, the person that did the, you know, the big review paper we talked to earlier.

• 25:03Speaker 00

  Yes.

• 25:04Speaker 02

  He brought up a lot of these same risks and he's like, this diet is not ready for prime time.

• 25:09Speaker 11

  So this isn't a diet that we're advising anybody to eat right now.

• 25:14Speaker 00

  So does Dudley restrict his protein?

• 25:17Speaker 02

  No, he's saying, no, he doesn't. He doesn't do it.

• 25:19Speaker 00

  No, not even he does.

• 25:21Speaker 02

  No.

• 25:21Speaker 00

  So this leads us to the very obvious question of when it comes to protein, what the hell should we be eating?

• 25:28Speaker 02

  Okay, so out in the real world, when you ask people what they eat and follow them over time, you get their food diaries, left to their own devices, people eat about between 10 to like maybe 25% of their total calories come from protein.

• 25:44Speaker 00

  Without even trying or thinking, you're probably in that range.

• 25:48Speaker 02

  Yes.

• 25:48Speaker 00

  Does it make a difference if you're in the higher range versus the lower range? What do we know?

• 25:53Speaker 02

  So we have loads of studies looking at that. They follow people eating this normal range. They look at the lowest protein eaters, they compare them to the highest protein eaters. They look at stuff like cardiovascular disease, cancer, death from all causes. And when we look at total protein intake, we don't see a clear signal that higher protein is worse and lower protein is better or vice versa. This is how Stuart puts it.

• 26:15Speaker 11

  It's effectively neutral. In other words, there's no good or bad.

• 26:19Speaker 00

  But then how does this make sense with that study? The small study of women that showed when they were restricting their protein, it was affecting their immune system?

• 26:28Speaker 02

  Because in real life, people are very rarely getting too little protein, like by accident. Like, you don't have to take protein powder to meet your minimum needs. You go out on the street, any, pull anyone off the street in New York City, or you went outside your studio and pulled anyone off the street in Melbourne, they're almost certainly getting enough protein to meet their basic needs without even trying.

• 26:49Speaker 00

  Uh huh.

• 26:50Speaker 02

  The one consistent thing we do see is that the source of the protein matters. So if you're getting your protein mostly from animal sources, especially like red meat, processed meat, that's associated with some worse health outcomes.

• 27:02Speaker 11

  It certainly does point towards plant-based proteins as a potentially healthier source of protein.

• 27:11Speaker 00

  Okay, so then I think my last question is just about protein maxing. So in these studies you just talked about where people are kind of eating in this general range of what was it, 10 to 25?

• 27:24Speaker 02

  Maybe 25, yeah.

• 27:25Speaker 00

  Percent of their diet, they're not going overboard. But now with this new trend, people are really spooning the protein in, which I think would...

• 27:40Speaker 02

  Some people.

• 27:41Speaker 00

  I'm sprinkling. Is this bad? Is it, is it bad? Because that is not, this is a new trend. It wouldn't have been captured in those studies you're talking about, right?

• 27:51Speaker 02

  I don't know what the protein maxers are doing in terms of like the percentage of their diet coming from protein. If it's higher than 25%, they're in kind of a known person's land in terms of the science. We don't really have many studies on those. Here's what Stuart said about that.

• 28:07Speaker 11

  We're conducting the natural experiment in real time. Call me back in about 10 years and we'll see whether this is playing out poorly or, or well for most people.

• 28:18Speaker 02

  So we don't really know if there's gonna be a downside for people going really hard on the protein.

• 28:23Speaker 00

  Hmm.

• 28:23Speaker 02

  But what we do know is that they don't need to.

• 28:26Speaker 00

  Mm hmm.

• 28:27Speaker 02

  There's this meta-analysis that looks at studies where people, they, they give people a ton of extra protein and have them hit the gym. And on average, the gains they got were like a quarter of a pound of muscle, like spread out through their whole body. So like tiny little gains from eating a bunch more protein. You just don't need it.

• 28:44Speaker 00

  Mm hmm.

• 28:45Speaker 02

  And in fact, Stuart, in our, in our last episode about protein, he told us how he, he did these experiments where you, you collect, you feed people a certain diet and, do you remember this? You collect their like fingernail clippings and their pee and their poop and, and you look for the nitrogen they excrete.

• 29:00Speaker 00

  And the period, I remember the period.

• 29:01Speaker 02

  Yeah, that was quite visceral. And but, you know, it turns out that you just excrete what you don't use.

• 29:08Speaker 00

  Of course, yes.

• 29:09Speaker 02

  And so you're, maybe you're not harming yourself, Wendy, with your, your protein sprinkling, but you might be wasting your money because you might just be peeing it out.

• 29:19Speaker 00

  I mean, also, this is, this is why I only sprinkle it. Because, because I look at the ingredients of it and it, it's, you know, it's 70% protein, 30% absolute crap. This is a boogum, emulsifiers, it's all this ultra-processed crap.

• 29:39Speaker 02

  Yeah, Stuart brought that up too. And he was like, you know, a lot of that stuff is basically junk food, like protein bars.

• 29:45Speaker 11

  That is a Frankenfood in terms of, you know, ultra-processed ingredients crushed together as, as a bar. I get it, like, they're tasty. Everybody goes, oh, they taste so good. And I'm like, yeah, sugar, a little bit of fat, a little bit of protein, blend it all together.

• 30:01Speaker 02

  I had a chocolate one the other day and I was like, I think this is a candy bar.

• 30:05Speaker 11

  I know. Yeah, I know. It's a dressed up candy bar. But, you know, if I had my choice, you know, we, we should all just have a piece of chocolate around three o'clock every day.

• 30:16Speaker 02

  Doctor's orders, gotta have your three o'clock chocolate.

• 30:19Speaker 00

  Ayy.

• 30:22Speaker 00

  It was a Fonzie reference. You got it?

• 30:24Speaker 02

  Yeah, I mean, it's been a while since I had access to Nick a Night, but I think that I think that is what the Fonz did. Ay.

• 30:31Speaker 00

  Ay.

• 30:34Speaker 00

  All right, Rose, you changing your diet as a result of all this research?

• 30:38Speaker 02

  Um, no, I'm not protein maxing. I'm not protein mining. Um, I haven't really changed a thing as a result of all this.

• 30:52Speaker 00

  So much research, so, so many papers that you've read to not change a thing.

• 30:59Speaker 02

  That's pretty good. The big question, Wendy, are you gonna keep sprinkling that protein powder on your yogurt?

• 31:07Speaker 00

  No, I'm not. I'm not. I'm not gonna, no protein mining for me.

• 31:12Speaker 02

  Yeah.

• 31:13Speaker 00

  But nah, I, I'm good. I mean, yeah, I was doing it just in case, just in case, Rose. That's how I get ya with the just in case. I don't need the just in case.

• 31:25Speaker 02

  No, I'm glad we had this talk.

• 31:26Speaker 00

  Yeah, that's Science Versus. How many citations are in this week's episode?

• 31:32Speaker 02

  Oh, um, this week there are 41.

• 31:35Speaker 00

  41? And if people wanna see them in all of their glory, where can they go?

• 31:40Speaker 02

  They can click on the link to our transcript. The citations are all in the transcript and they can find that link in our show notes.

• 31:46Speaker 00

  Cool. Bye.

• 31:48Speaker 02

  Bye.

• 31:50Speaker 00

  This episode was produced by Rose Rimla with help from Merrill Horn, Michelle Dang and Akedi Foster Keys. We're edited by Blythe Terrell. Wendy Zukerman, me, I'm the executive producer. Fact checking by Marlo Starling. Video editing and sound by Bobby Lord. Music written by Bumi Hidaka, Peter Leonard, Emma Munga and Bobby Lord. Thanks to the researchers we spoke to for this episode, including Dr. Edward Giovannucci, Professor Holly Brown Borg, Professor John Speakman, Dr. Ming Yang Song and Dr. Jessica Bisakurski. And an extra thanks to Humdinger Studios in Melbourne and Wolf Island Studios in New York City. Science Versus is a Spotify Studios original. You can listen to us for free on Spotify or wherever you get your podcasts.

• 32:33Speaker 00

  You can also find us on YouTube, TikTok and Instagram. So please come and say hello. I'm Wendy Zukerman. Back to you next time.

• 32:43Speaker 10

  Whenever fall comes back around, it always feels like a fresh start. This year, I've been layering in some styles from the new Lululemon fall drop because the weather is shifting and I find I have to be ready for the entire day and not just one part of it. Lululemon's fall line has some really versatile transitional pieces. So I can just wake up, throw on a matching set, add a jacket or a fleece and head out, knowing that I'll feel comfortable enough to go wherever the day takes me. Check out the new fall arrivals in store and online now at lululemon.com.

• 33:15Speaker 12

  This episode is brought to you by State Farm. No two football players are exactly alike and the same is true off the field. That's why State Farm gets to know you so they can help personalize coverage for your life and budget. And like a good neighbor, State Farm is there.