What's the Deal with Colostrum?

Perry: [00:00:00] Emily, when you pitch the idea of talking about colostrum to me, I thought of the human substance that comes from that comes from breasts. Yep. After a mother has a baby and you're like, no, no, no. It's huge in the endurance athlete space. And I'm, I have like these horrifying visions of like, like human women in factories, this totally dystopian view. And then I learned that this is not humans where this colostrum is coming from. Thank you God.

Emily: [00:00:39] It is still a little dystopian and we can get into the baby cows. But I will tell you that when people first started asking me about should I take colostrum, I assumed that they were talking about their own colostrum. And often this question was phrased like, should my husband take colostrum? And it's like, well, there's only a tiny amount of it. Like, [00:01:00] you know, if you have a baby that colostrum, it's like the first milk that comes in, it's thicker, it's more yellow, but it's like so little. And it's like you're desperately trying to get some of it out for your baby. It's like you. What do you mean? Your husband's like.

Perry: [00:01:13] This guy's got to run a marathon tomorrow.

Emily: [00:01:15] So what, he's going to go cycle like, are you kidding me? And so, uh, we are talking about bovine colostrum in this episode, not human colostrum, which is a great food for babies, but should not be shared with your spouse, even if they have a large endurance event coming up shortly.

Perry: [00:01:34] Cow colostrum. Coming right up.

Emily: [00:01:38] I'm Emily Oster, I'm an economist and a data expert.

Perry: [00:01:42] And I'm Perry Wilson. I'm a medical doctor.

Emily: [00:01:44] It's Thursday, May 7th, 2026. And this is Wellness Actually.

Perry: [00:01:50] Because you're getting a staggering amount of health and wellness information nowadays from every source imaginable. And some of it is awesome.

Emily: [00:01:58] And some of it is, [00:02:00] well, actually bullshit. Fortunately, we're both people who know how to read studies, how to parse the data, and can tell you what's worth thinking about and what you can safely ignore.

Perry: [00:02:11] But before we dig in a note that this podcast is for educational purposes and should not be construed as medical advice. We don't know your unique situation, so talk to your doctor for personal health decisions.

Emily: [00:02:22] This week we're asking what's the deal with colostrum? Perry and I will give the official smash or pass, and then we'll get to your question of the week. But first let's do the health news roundup after the break. And now for the health news of the week. Perry, I want to start with a new trial in alcohol use disorder about ozempic, which I thought was really exciting. Did you [00:03:00] think this was exciting?

Perry: [00:03:01] This is super exciting. The context here is that since Ozempic has been a thing and been in diabetes and weight loss trials, there has been this. I don't know if you even want to call it a side effect, like an additional effect which has been reported, which is people saying, I'm not drinking as much alcohol and other things like not smoking as much other sort of compulsive behaviors, but it hadn't really been formally tested. Like, let's do a trial specifically with this as the outcome. It was always just sort of icing on the cake. But this week, we have a new randomized trial appearing in The Lancet, which randomized 108 participants about half men, half women. They all had alcohol use disorder. They all also had obesity. So they did have a like an FDA indication for ozempic. But the purpose of this trial was to see if the people that got ozempic versus placebo would have a reduction in days with heavy drinking. And indeed, they did a 41% [00:04:00] reduction in the ozempic group, compared to a 26% reduction in the placebo group. That was statistically significant. And there was a bunch of other secondary effects that also suggested significantly less drinking. So, I mean, it's good news.

Emily: [00:04:17] It's really good news. I mean, we have relatively little treatment for alcohol use disorder. There are some medications, but they have pretty substantial side effects that make people not want to use them. Like they basically work by making drinking very unpleasant. And so this obviously works in a different way when people describe it, at least anecdotally, it's more like you just don't want to drink, which is obviously much better than wanting to drink, but then feeling bad when you do. So I thought this was really exciting. I think we'll be seeing more like this. I'd like to see some work on narcotics also, but I think that's probably down the line.

Perry: [00:04:52] Yeah, 100%. I mean, the big caveat here is that it does make you lose weight. And so this is not necessarily a therapy for people [00:05:00] who are of normal weight to begin with. Or, you know, as some people with severe alcohol and drug use disorders have are quite a bit underweight. So that'll sort of take this, um, out of the picture for them. But really interesting to see some corroboration of the observational data on ozempic and alcohol use disorder. Um we need to close the book on perennial surgeon general candidate Doctor Casey Means. Emily, uh, we.

Emily: [00:05:26] Over.

Perry: [00:05:28] The saga is over. I like to think we played, you know, perhaps a small part in the saga. So talk to me about no longer Surgeon General candidate Casey Means and where we are with this position that has been vacant for a long time.

Emily: [00:05:42] For a very long time. Yeah. So, um, so the surgeon general position has been vacant for a long time. I think it's an interesting question of kind of is that something we should be concerned about? The Surgeon General is in some ways a largely symbolic role. And so we're not exactly missing a lot of things. [00:06:00] Milestones, let's say. But it is a role that needs to be filled. Casey Means has been on the ropes in terms of approval for many months now. It's been she, I think, was caught up in this in the backlash wave to some of the anti-vax activities of the RFK administration. You know, people have, uh, lost patience. Some people have lost patience with the, uh, resistance to vaccines as more and more people.

Perry: [00:06:31] Senator Bill Cassidy, notably.

Emily: [00:06:32] Bill Cassidy, noticed a lot of people got measles, and he noticed that whatever deal he had made with Kennedy was not followed through on. And he's had enough. Uh, and that has tanked the nomination. The white House was not interested in getting, uh, losing further capital on this. And they have now nominated someone named Nicole Saphier, I believe is how you say her name, who seems like a very standard up the middle candidate.

Perry: [00:06:57] Yeah, up the middle for this administration, I would say.

Emily: [00:06:59] She's [00:07:00] a doctor, Perry. She's an actual.

Perry: [00:07:01] No, I'll take it. I will take.

Emily: [00:07:02] She's a.

Perry: [00:07:03] Doctor. She's a real doctor. She's a breast radiologist at Memorial Sloan-Kettering.

Emily: [00:07:08] She has a reasonable she's a Fox News contributor, but she's a real doctor. And I feel like that's my that's my bar. Okay. She's a doctor.

Perry: [00:07:14] Great. Go. And I imagine she will get confirmed unless the position is truly cursed. As we have speculated on earlier episodes of this podcast.

Emily: [00:07:23] We'll see. I think she'll be confirmed. We have to see. All right. Last question. There is an outbreak of hantavirus on a cruise ship. People are stuck on this cruise ship off the coast of, I believe, West Africa. And a lot of them have hantavirus. Please tell us what is that and should people be concerned about it?

Perry: [00:07:46] Yeah, yeah. Let's let's do the hantavirus primer. So hantavirus is an RNA virus that exists all over the world. It is carried by rodents. The rodents generally are asymptomatic. So they just kind of carry [00:08:00] it around and they leave it in their feces and urine. And then when you go to clean up feces and urine, that virus gets aerosolized. You inhale it and it can cause very severe disease. Um, in the new world, the there are two main forms of hantavirus. Two species. The one that we would worry about here is called Andes virus, which is common in Argentina, where the cruise ship left from Andes virus has two notable features. One is that it is the most lethal of the Hantaviruses, with about a 30 to 50% case mortality rate. Also, it's the only hantavirus that has been shown to be capable of transmission person to person, as opposed to mouse to person. Okay, that all sounds scary, but I'm going to turn this down. I'm going to turn this down just a little bit. You know, so far I think there are only five people with that that have symptoms now. Three people have died from from from this. So I mean, this is this is severe on the cruise ship, but it's [00:09:00] not like the whole cruise ship was infected. I think that's important. Also, two of the people that died were husband and wife. So if there was person to person transmission, which is suspected in Andes virus, it does require very close contact and like exchange of bodily fluids and things like that. This is not an airborne virus. So, you know, the public health risk is quite low unless you're interacting extremely closely with someone who's infected. The argument to quarantine this ship is actually not strong. I don't think because of that, the risk really comes from the droppings, not from the people who are infected, who need to be in hospitals and getting very close supportive care. There's no treatment. But, you know, they need to be in intensive care unit.

Emily: [00:09:44] Yeah. But on the other hand, uh, people, we're hundreds of years into people being concerned about diseases on boats being spread to the population. And so we're not that surprised that we are quarantining this ship. I do want to say that a [00:10:00] lot of people do get sick on cruise ships, but this is not like a major risk factor on cruise ships. The main disease you get on the cruise ship is the norovirus, which is almost 100% chance of getting.

Perry: [00:10:10] Yeah, yeah. Once norovirus breaks out, it's it is all over.

Emily: [00:10:14] You're getting it. But this is rare, although obviously scary.

Perry: [00:10:19] It does add to my ever growing list of reasons. I never want to go on a cruise, but this is the first case I've seen of hantavirus.

Emily: [00:10:26] I don't I don't go on boats due to a stomach issues.

Perry: [00:10:31] We should just say people, if you're cleaning up your house and you're worried about mouse or rat droppings, um, you want to spray those with a bleach containing solution before you clean them up and ideally not vacuum because that can really aerosolize things. There is hantavirus in the US. Gene Hackman's wife died of hantavirus, although apparently there were a lot of, um, there was a pretty bad rodent infestation in the house. So, you know, be careful. But this isn't something to panic about quite yet.

Emily: [00:10:57] Be careful, but don't panic. Yep. All [00:11:00] right. That's it for the health news of the week after the break. What's the deal with colostrum?

Influencer: [00:11:10] This is raw colostrum. So powerful it's actually banned in NC double A yes. College sports banned colostrum because it contains IGF one insulin like growth factor one. It's associated with increased muscle growth and vitality, increased levels of HDL in humans. Colostrum also contains a ton of different immunoglobulins which support the health of the gut. Also, proline rich peptides like Colostrinin that support the immune system and the thymus. This stuff is liquid gold. It's the first milk cows give to their calves, and it helps program their gut and across species, mammalian milk is very healthy for humans. So if you can find somewhere to get a colostrum, preferably a raw colostrum, this stuff is incredible for your gut, for your immune system, incredible for muscle growth and recovery. I love this stuff. However you can get it. Colostrum is a superfood banned by the NCAA. Good for me, good for you. The stuff is amazing. I'm going to go home and drink a bunch of colostrum right now.

Emily: [00:11:58] I love that clip, Perry, because I think [00:12:00] it illustrates a very common wellness influencer talking point, which is, you know, this is like, why would they ban this if it wasn't great?

Perry: [00:12:09] I mean, we've made that talking point several times.

Emily: [00:12:11] Yes. I'm always making that point. Like, you know, this must be good for performance if they ban it in professional cycling. So I'm convinced. But before we talk about how we should all be consuming the milk of that is intended for baby cows, I think we should talk about what this is and and why it might be helpful. So let me start with the what it is, and then I'm going to pass to you for like what might possibly be going on, which is, you know, so bovine colostrum is the colostrum from cows. Literally. So it's the first milk that is produced by the female lady cow after she calves. And it has like human colostrum has a different composition than more mature human breast milk. Bovine colostrum has a different concentration of various features than [00:13:00] mature milk. And the idea is that somehow this would be helpful for something. And I actually, relative to some of the things we talk about, those fill ins are to me, very vague. This is a lot of it feels like that influencer clip where it's just a list of things that one might be interested in and how they might be good here, but with no real connection. Yeah. So is there something biologically behind anything here?

Perry: [00:13:30] Yeah. It's always so complicated when we're talking about like a natural substance instead of a chemical or a single chemical, right? Even when we talk about something as simple as coffee and like, oh, this study showed that coffee was beneficial for X, Y, or Z. And it's like, okay, well, coffee is 8 million different things, right? Yes, there's caffeine, but there's also all this other stuff and it's very hard to untangle. And colostrum is no different. It is clearly a biologically very important substance. All mammals produce [00:14:00] colostrum before they produce milk. And as you pointed out, it is quite a bit different from like, you know, the milk that comes in later and animals that don't get colostrum from their mother, um, early certainly do worse in a variety of ways. So it is something important. I think when I was kind of listening to, you know, what influencers are talking about and people who support colostrum a lot, there's a few substances in there that kind of keep getting mentioned. And I think we'll probably want to focus on those as like the biologically relevant ones. The first is probably IGF one or insulin like growth factor one, there are anywhere between 50 and 2000 micrograms per liter of IGF one in cow colostrum, compared to less than ten micrograms basically undetectable in mature cow milk. This is from the Bulgarian Journal of Veterinary Science. You know, not maybe the number one veterinary journal in the world.

Emily: [00:14:59] Not a very high impact [00:15:00] factor, but okay.

Perry: [00:15:01] But actually the best study on like the content, the actual measurements of what's in this stuff that I could find. Um, so, and I think let's, if, can we talk about IGF one as like, because I think this will give a framework for how to think about stuff that you eat. So what IGF one is, is the molecule that mediates the effects of growth hormone. So your pituitary gland releases growth hormone particularly when you're growing. And downstream that tells your body to grow. Tells your bones and your muscles to grow and for you to get taller. That's what growth hormone does. But it doesn't do it itself. It doesn't act itself. It acts on the liver to release IGF one. And then IGF one is the thing that tells your muscles and stuff to grow. So it's just a two step process. Okay, that's IGF one. Kids who are born with genetic deficiencies of IGF one or growth hormone have congenital short stature syndromes. Um, so, you know, little people, types of syndromes. Igf one is banned by the NCAA and the world Anti-Doping Association. [00:16:00] You can inject IGF one because it does grow muscles. It is a growth factor. Um in fact, there was concern about some people who are concerned about our intake of dairy point to IGF one and their like dairy causes cancer because of IGF one, right? Because of the growth signals from IGF one. So you always get these millions of sides. But there's a couple of things we need to think about when it comes to a cow product. Number one, are we pasteurizing it? If we're pasteurizing it, some proteins lose their functionality, some don't. Number two, Can it get absorbed intact through your GI tract? And this is the big one where kind of a.

Emily: [00:16:38] Lot not.

Perry: [00:16:39] Of the biological plausibility falls apart when it comes to IGF one. And this will be the case for multiple things. That's in cow colostrum. You can give it to people. In fact, it's heat stable IGF one. So you can even pasteurize this stuff and it still has IGF one in it, but it does not get into the blood. Some studies that suggest it does get into the [00:17:00] blood see fragments of IGF one, but that's just digested stuff. It's not the actual molecule.

Emily: [00:17:05] Yeah. I think this point comes up actually a lot in this space of linking. You know, this is a substance in this food to this is going to have this impact where we know the substance is something where like if you injected it in mice, right? Like really what you're saying here is like, if you take IGF one and you inject it in a mouse or even in a person, yeah, like that's good. You know, that's why they don't let you.

Perry: [00:17:28] It's not necessarily good for you, but it'll make your muscles grow a bit.

Emily: [00:17:31] Yeah, it'll make your muscles grow. And so you can get a super muscular mouse by injecting them with IGF one. But our digestive system is not the same as injecting things. Not at all. Like when you when you consume something, it goes through your stomach and your stomach is full of acids and other stuff, and it breaks it down in all kinds of ways. And so there are many things, for example, even GLP ones, where there is a reason it's taken a long time to get to an oral GLP one, because the injected version is just so [00:18:00] much more accessible to our body. And so I actually believe if we looked into it, there's many things in the space where that that is the link that kind of breaks when people go from here is something where we know if we inject it in a mouse, it would matter to. Here is something you can take by mouth, because the amount that you have accessible after you consume it through your stomach is like nothing.

Perry: [00:18:24] Yeah, yeah, it's really hard. And pharmacologists spend a lot of time trying to figure out how to get your body to absorb something without digesting it. It's it's just a tricky problem and it's not solved in colostrum. So I'm actually, I think that like a colostrum, if you dig into the NCAA rules on this, the reason they ban colostrum is actually they say that it's risky because potentially of false positives in your blood. It's like similar to how like you might not want to eat a lot of poppy seeds if you're getting like an opioid test, right? It's not because the poppy seeds make you high, it's because they have kind of similar chemical structure. Maybe [00:19:00] you get a little pieces of IGF one in your bloodstream after it's digested, but then the test that they give you is like, oh, he's using IGF one.

Emily: [00:19:07] So fun fact, Perry, a lot of people, when they get popped for doping, the excuse is I ate a food where the animal was fed growth hormone.

Perry: [00:19:16] Okay, there you go. Yes. Um, you know, that is why I exclusively drink milk that has been extensively treated with bovine growth hormone.

Emily: [00:19:26] Growth hormone when they test you at the end of the five K.

Perry: [00:19:30] I'm not getting tested. I'm just trying. I'm just trying to hit the golf ball further. That's all I care about.

Emily: [00:19:35] Just trying. Okay, so when we look at the particular items in colostrum, and I think this is important to set the stage for, for like looking at the, at the data on it, there's the growth hormones. There are a bunch of other things. Immunoglobulins.

Perry: [00:19:52] Yeah, we should definitely talk about that.

Emily: [00:19:53] I will say we should talk about all these things. But big picture, one of the issues with biological plausibility for [00:20:00] this substance at all is that almost all of these things are not really available once you eat them.

Perry: [00:20:06] Yes. That's correct. Most things are digested. I'm going to like put one coin on the other side of the scale though. Let's let's give colostrum its due. Not everything that affects your body has to get into your body. True. And so so for example, immunoglobulins, immunoglobulins are little. Those are antibodies, and your body makes them against certain antigens like bacteria, viruses, stuff like that. The antibodies stick. They're each specific to one of those antigens. They stick to it. And it's sort of a signal to your body like this is a bad thing. It's marked for death, like take care of it. And the whole cascade immune cascade follows. There are different types of immunoglobulins, but one that's very relevant here is called IGA immunoglobulin A, which is the immunoglobulin that lives in your mucosal system. So in your nose, mouth, throat, and GI [00:21:00] tract, this is the frontline immunoglobulin. It's actually secreted into the mucosa by your body. Um, and it's directed against antigens, the many different bacteria and pathogens and stuff that you will get just by breathing air in a non-sterile environment, by eating food that hasn't been sterilized, like we always do, etc.. And colostrum contains IGA. And so that IGA can actually stick and mark some of those antigens potentially while they're sitting there in the GI tract. And it's conceivable that that would promote an immune response to some antigens. Some scientists also point out that some of these molecules, including even things like IGF one, yes, they don't get into the blood, but they can potentially signal to the gut epithelium because those are cells, right? Like they're just half of them are sitting out there, you know, in the lumen of the GI tract. And the IGF one can kind of float by and at least act on them. And you get people saying, like, this promotes gut health [00:22:00] and stuff like that. So yeah, the idea that you're getting like, you know, a secret way to take anabolic steroids by drinking this stuff, definitely not true. But there may well be some physiologic effects here.

Emily: [00:22:14] Okay. So I think that that is a good place to turn to the question of what we see in the data, because always with stuff like this, you can sort of start with like, is there a biological plausibility? I think in this case, it's like a little bit maybe. But then the question is, when you look into people, are we actually seeing any any impacts? And the, the outcomes here that there are actually two groups. We can talk about them in turn. The first is there's actually a lot of work on this in athletes. Yay. My favorite. And then work on people. Yeah.

Perry: [00:22:52] Right. Actual people. Okay, I like that there's athletes and then.

Emily: [00:22:55] People, not elite male cyclists. Um, and then and sort of we're [00:23:00] looking at like something about inflammation, the gut, maybe performance, maybe respiratory viruses. Part of what's hard here is the range of outcomes that we're looking at are so broad that it feels like, like, how could it possibly, how could this thing possibly matter for all of these?

Perry: [00:23:18] Yeah, it's a problem. And of course, because there's so much stuff in colostrum, there's always going to be a biologically plausible route, right? Like you're given all these Lego pieces and you can be like, oh, I can make a car and I can make a boat and so on and so forth.

Emily: [00:23:30] Is it just, it's always a just so story. You can sort of say, okay, I'm going to look for this in the data. Maybe I'm going to like pee a little bit through a bunch of different outcomes. And then I'm going to make up a story for why the particular peptide that's in this matters for that. So I think that's a that is a caution with everything we will say here.

Perry: [00:23:47] Absolutely. But, you know, I as I was looking through this, I definitely saw, you know, a number of trials in these athletes. And all I could think reading them was like, I've got to get Emily's take on this. So can you, can you walk me through how you [00:24:00] as an athlete can talk to me as a human about the data here?

Emily: [00:24:07] So what I really like about studying athletes and what I think researchers like is that, you know, the outcome you are looking for. And it's very easy to measure. So like an example of a of studies, just like a study. It's a pretty old study from the British Journal of Sports Medicine, but it's like very consistent with this whole research space.

Perry: [00:24:27] And we love the British Journal of Sports Medicine.

Emily: [00:24:29] That's actually a very good journal.

Perry: [00:24:30] Yes it is.

Emily: [00:24:31] So this is like we take they take 29 highly trained male road cyclists. That's everybody's favorite. Everybody loves a highly trained male road cyclist. And then you stick them on the bike and you have them do time trials. And then you give them some colostrum and some not colostrum. And, and or in this case, I think it was some of the time they had the colostrum and some time they, they didn't. There's all kinds of like detailed ways you can control this. And then they [00:25:00] look at whether their time trial, VO2 max performs. It's just like there's a lot of outcomes you can very clearly measure. Yeah. And so in a set of studies like this, you do see some impacts on performance, maybe some impacts on respiratory illness. In some of this we see a little bit in recovery for runners. Uh, you know, a lot of it's a lot of cyclists.

Perry: [00:25:25] Yeah. I want to put numbers on this and I, I don't know how good this is, but I'm hoping you do. So I'm looking at the British Journal of Sports Medicine study. They did a 40 kilometre time trial either on colostrum or on whey protein was the control I think. And their performance improved by 2% versus baseline. Like to me, as a human, that is not an athlete 2%. I'm like, oh, that doesn't sound like great at all. But is that actually something where it's like, dude, like if you're an elite male cyclist, this is the difference between first [00:26:00] and second place. Like, like, what are we talking about here?

Emily: [00:26:02] Yeah. I mean, so look, 2% is there's two ways to think about 2%. One is to say like, if you're at the end of the tour de France and you're trying, you're like Jonas Vingegaard and you're trying to get tied up at the top of the, you know, cul de blah de blah, like you would take a point.

Perry: [00:26:21] Those made up names.

Emily: [00:26:23] Uh, those are people. Jonas, Bingo and Pikachu are people I don't know which call the call is, you know. Okay. Anyway, you would take like a half. I mean, that's that's the difference. These guys are are biking for hundreds and hundreds of miles and winning by four seconds. Okay.

Perry: [00:26:37] All right.

Emily: [00:26:38] For more regular people, uh, I think 2% is pretty good. It's like not as good as it's not as much as the benefit you'd get from really like ramping up your fueling, which is like a sort of core element of improving your, your performance. But it's like, that's like a solid, like people would take people who love people who are highly trained [00:27:00] male road cyclists would definitely take 2%.

Perry: [00:27:02] Okay. So that sort of confirms my impression, which, you know, there are several studies like this where you see, you know, relatively small studies, relatively small effect sizes. And I think we do need to say to people that that raises your eyebrows a little bit. From a data science perspective, in part that's because of publication bias. So just is worth saying that like if you conduct a study in 20 people and the results are negative, it's just hard to get it published. Like I've been there, by the way. Um, and you submit it to a journal and they're like this, like, why we don't care. Like nothing happened. You only enrolled 20 people. Like if you enrolled 1000 and nothing happened, then, you know, sure, we'll publish that because that's a big study. But for 20 no, not really. But if you enroll 20 people and you do see a modest effect or even a tiny effect, but you know, that passes statistical significance threshold, you're much more likely to get it published. So we do kind of one of [00:28:00] the meta analytic things we think about here is like, if we're seeing all if we're seeing several studies, but they're all very small, we worry a little bit about this, um, about this issue of publication bias. Um, yeah. But you know, hey, if you're an elite male cyclist and this is how you make your living, um, you know, it seems like you can give it a shot, I suppose.

Emily: [00:28:24] Yeah. I mean, I find yeah, maybe. I mean, I think, I think the publication bias piece here is pretty, pretty important. Um, and.

Perry: [00:28:34] Yeah, you got to say it right. It's like the literature is not perfect.

Emily: [00:28:37] This is a place where, you know, we like, I think the really great next step, if one was really interested in this is to say, okay, let's take these theory like we've got a bunch of data that would suggest particular outcomes that have been seen before. Let's redo with a larger sample, looking at those outcomes, which would get away from p hacking, like you're just choosing your outcomes based on which ones work and would get away from some [00:29:00] of the publication bias if you could kind of preregister, but I don't know. I think we can get into the people thing. What's hard here is like, I have no idea why this would matter. Like nothing in the biology of the. This substance would suggest that it. Connects to. It's not like protein or creatine or something where you could say, okay, I can see mechanistically why this matters for performance. It's just sort of like it's just like a really good protein shake.

Perry: [00:29:26] Yeah, yeah. There's just kind of like good humours in it. And, you know, these studies were controlled for protein intake by giving whey protein. So, um, so yeah, we like some, some plausibility. And I think actually the, the place that has more plausibility is in the data looking at like respiratory infection.

Emily: [00:29:44] Yeah.

Perry: [00:29:45] Rates. Um, so this is a place where we actually have some larger trials also kind of relatively on the, on the old side. Um, but the reason I think there's some biologic plausibility goes back to [00:30:00] that immunoglobulin a phenomenon. So again, you know, if you're putting something in your, in your GI tract that has a lot of immunoglobulin A in it. And presumably these cows are making immunoglobulins against at least some of the same pathogens that, you know, humans are exposed to. Maybe that can rev up your immune system. So I'll, I'll highlight one study because it was relatively large from the European Journal of Nutrition, also old 2003. They took 174 adult men. This actually was a little bit a little bit of a weird design. They created this study out of other randomized trials of colostrum versus whey, and just looked to see who reported as an adverse effect upper respiratory symptoms. So this wasn't the primary outcome. So it is randomized, but they're kind of like they're like convenience looking at the outcome. And over the seven [00:31:00] weeks that they looked at, 32% of the colostrum subjects reported some upper respiratory tract symptoms could be anything from a runny nose to a sore throat, versus 48% in those who were getting whey protein. So and that was a significant decline, you know, and there sort of other studies that go along this line. There's even been some studies in medical people like who are exposed, you know, presumably exposed to.

Emily: [00:31:31] To there's a study in preschool children who are exposed to.

Perry: [00:31:34] Talk to.

Emily: [00:31:35] Me about even more.

Perry: [00:31:36] Oh my God, yeah, yeah.

Emily: [00:31:37] Yeah, yeah. So, so there is a like six week long study of colostrum in preschool children. It's relatively small. It's like 60 kids, um, 57 kids, uh, and they randomized kids into colostrum versus not. And there was a reduction in days with upper respiratory symptoms, 31%, [00:32:00] which is large.

Perry: [00:32:02] Yeah. That's not.

Emily: [00:32:03] Nothing.

Perry: [00:32:03] Parents take 31%.

Emily: [00:32:05] Parents would definitely take that when they are parenting preschool children. So so yeah, we do see this in a number of different settings. I will say I'm still worried about the P hacking and the small samples and the publication bias. I think I just I'm still worried about that here.

Perry: [00:32:25] It's always going to be the case when we have multiple small studies. That preschool study also had parental reported outcomes, which I don't know, you're not going to ask the kids, obviously, but that does open the door. You know, this isn't like they were tested in some way for, you know, viral carriage in their nose or something that was objective. This is a subjective perception of if the kid is doing better and if blinding is inadequate, like if there's, if the parents had any way to tell like, oh, this, my kid's getting colostrum versus my kid's getting whey protein, then that can kind of bias the results. So there's just, you know, this is, this is medium to low to medium quality data [00:33:00] pointing in a direction. And there is some biological plausibility here, but we do have to be really careful in interpretation.

Emily: [00:33:07] Why? Can I ask you, before we get to the second piece of this, which is the gut health, leaky gut. My favorite topic?

Perry: [00:33:15] Leaky gut.

Emily: [00:33:15] Why do you think we do not have larger scale trials here? I mean, I understand why maybe we don't have larger scale trials in in sports because people don't don't care that much. But, you know, let's say there was something that you could give your kid that would cause a 31% decrease in upper respiratory infections. Like I, that seems pretty important. And so I'm a little bit confused. And it's not like these studies were published in 2025. It's like, oh, somebody's doing that. Like, what do you think is in the way of what we'd really want here? Large scale randomized control trial, really evaluating this.

Perry: [00:33:48] Yeah. I mean, money is the is the answer. So, you know, colostrum is recognized by the FDA as a dietary supplement. So that has two implications. Number one, it doesn't have to be [00:34:00] vetted. They have to adhere to certain good manufacturing practices, but it's not like tested by the FDA. There's no they don't need to prove that it's efficacious or that it is safe. It's generally recognized as safe. It's like a food product, which means there's really no moat like anyone can sell colostrum. And so, you know, in theory, if you, you know, if you're a big pharmaceutical company that's going to fund a multi-million dollar trial, you want to be able to sell your thing for more money, at least until your patent runs out. And that's not possible here. What can happen? And the way this often works when there are signals from natural substances, is that pharmaceutical companies will go in and try to pull out what molecules might be mediating this effect and then, you know, patent and do a trial on that molecule that often doesn't work. Um, because, you know, it's not because there's like a magical combination of things and you need the magical combination to work like a la original Michael Keaton. [00:35:00] Batman. Hello Gen X, how are you today? Good, good. Um, it's that you are often wrong about the the substance that you've like put your knuckle down on. So I think that's the, that's the main problem.

Emily: [00:35:12] Yeah. I mean, I think I totally agree that's the main problem. This is one of my frustrations with like the NIH, um, and other like government funders because I feel like.

Perry: [00:35:23] Yeah, they could do.

Emily: [00:35:23] This, they could do this. They could just be like, you know what? Pharma is not going to do this. You know, pharma is, it's not a pill to make your penis grow faster or whatever, which presumably pharma is into. It's just something that could potentially improve a lot of people's lives. And we could we, the NIH, could fund someone to run this trial, which wouldn't actually, by the way, be that expensive. It's like how I feel about breast milk storage. And I have a lot of feelings about the things the NIH.

Perry: [00:35:47] And this actually feels kind of aligned with the Maha agenda, right? It's like, this is a natural thing. And you could even imagine a whole NIH institute who's like, okay, we're going to test the stuff that like no one else, you know, that's cheap, [00:36:00] that's widely available, that's not patented. And if it doesn't work, fine, great. We learned something. And if it does work, we have this great new public health intervention that is widely accessible to everybody. It seems like a great use of funds.

Emily: [00:36:11] I agree. Jay Bhattacharya Jay, if you're still talking to me after the interview I did with you last week, um, I have some this is my suggestion.

Perry: [00:36:21] Make it happen. Jay. Doctor Jay.

Emily: [00:36:23] Jay, let's do it. Okay. Um, all right, so let's talk about the last sort of set of big things that come up in colostrum, uh, which is leaky gut, intestinal permeability, leaky gut. It's so popular with the wellness influencers. Nobody wants it. Where is it leaking to? Perry? Where is it going?

Perry: [00:36:42] It's God. The wellness influencer marketing is so much better than like everyone else. Leaky gut sounds terrible. Talked about glucose spikes before. Like it's really good. No one wants a leaky gut. Okay, first of all, it's very important that your gut is leaky because [00:37:00] if nothing got through your gut, you would die. So let's set the table here. Um, intestinal permeability is the medical term for what's going on. And your intestine is supposed to be permeable to a wide variety of things amino acids, proteins, glucose, other substances, etc.. That's what your gut is for.

Speaker 4: [00:37:22] This is because as the food moves.

Emily: [00:37:24] Through your small intestine, that's when the stuff comes out of it. It goes through your small intestine and stuff comes out and goes into your bloodstream, and that's how you get nutrients.

Perry: [00:37:30] That's correct. And you want that. Um, now you can measure intestinal permeability in the lab. What you do is you give someone a dose of some substance that should not be absorbed very well, like something like mannitol, for example. It's like a poorly absorbed sugar type of thing. And then you measure it in their blood. And you can certainly show that there's variation across people. Like some people, they take the mannitol and like there's more in their blood and some people there's less. And scientists have shown that people with comorbid conditions, [00:38:00] like people who are sicker, often have a leaky gut by that definition.

Emily: [00:38:04] Which means more stuff that should not be getting through is getting through.

Perry: [00:38:09] It's not even necessarily that should not be getting through. It's just like that usually doesn't get through. If you appreciate sort of where I'm going with that. Um, but, but there's this real causality problem here, right? Like a lot of wellness people will be like, oh no, it's your leaky gut that causes the diabetes or the cancer or the dementia or like whatever it is, as opposed to it's the diabetes or the cancer or the dementia that causes the leaky gut. And we don't know the difference there yet.

Emily: [00:38:41] It's, it's sort of I mean, another way to say this is like, even if colostrum were to fix your leaky gut, it isn't really obvious that the leaky gut itself is really a particular issue. It is just a thing we see Rising that is higher among people with certain conditions, but also in other like this is like a, a problem that [00:39:00] athletes have. Like when you stress your body, stuff gets.

Perry: [00:39:03] Absolutely. Now in the medical space, there is this phenomenon called bacterial translocation, where someone comes in with a bloodstream infection with bacteria. This is bad. You don't want this. This is.

Emily: [00:39:14] Sepsis.

Perry: [00:39:15] Sepsis. And when someone comes in with that, we zoom around and we look for what the source of the infection is. And we we identify the infection. We're like, okay, is there a skin lesion that spread to the blood? Do they have pneumonia that spread to the blood? Like, where did it come from? And every once in a while you cannot find the source. And if it's a gut organism like E coli that's in the blood, all you're left with is like, did the E coli, like escape from the gut? And bacteria are a lot bigger than glucose molecules, right? So like bacteria should not be translocating the gut, but in very stressful situations, It can. Um, and the reason I'm mentioning this is because of one study looking at this phenomenon, actually [00:40:00] in 62 children who had newly diagnosed leukemia, all leukemia. And one of the problems when you're getting chemotherapy, you know, pretty intense chemotherapy like this is that you can affect the intestinal lining and you can get bacterial translocation. And if these kids get sepsis, they're in big trouble. We don't want that to happen. So anything you could put in there to prevent bacteria from getting out would be great.

Perry: [00:40:27] So they randomized these kids to um oral bovine colostrum while they were getting that induction chemotherapy versus a control. And they were looking at fever, um, as well as bacteremia. And there was no difference in fever or infection rates. Um they look at fever by the way, as a marker of like, maybe the bacteria got in, but then you fought it off before we detected it and like caused a fever response. So no difference in fever or infection rates. But there was a secondary outcome that was positive here, something [00:41:00] called mucositis, which are like these ulcers that develop in the mouth with intensive chemotherapy. It's incredible painful. That was improved by the colostrum. And so I'm setting this in terms of like, this is the leakiest gut you can have where you're actually worried about bacterial translocation causing, you know, sepsis and death. Colostrum is not preventing that phenomenon. That's our starting point. Now we can kind of walk this back to maybe your average everyday person who's worried about, you know, their own gut health.

Emily: [00:41:32] And when we walk it back there, I would say there is a bit of evidence. Again, the evidence is probably stronger in sports than in non-sports. You know, the to the extent that the stress of like intense exercise increases the permeability of the gut, which we know that it does. This seems to to some extent truncate that that rise. And so kind of, I don't [00:42:00] know, we'll off the gut a little bit, I guess, which is interesting and I guess is potentially some of the mechanism for some of the performance effects, although I'm not sure why that would why that would be.

Perry: [00:42:11] I don't either. I just I don't know why leaky gut is, is bad, right?

Emily: [00:42:16] I mean, I think there's a fundamental thing which is outside of this kind of setting that you're talking about with, with, you know, kids who are very sick where this could potentially lead. Like it's not really clear why you would care about fixing this, why you would care if you had it, why you would care about fixing it if you were an otherwise healthy person. So observing that this fixes that, okay.

Perry: [00:42:34] It's not enough. You've got to you've gone from A to B, that's great. Now go from B to C, now show me that you have improved exercise performance. And hey, there's, there's a little bit of that. This is a potential mechanism. But again, small effect sizes in small studies.

Emily: [00:42:52] They do you know, they look at like diarrhea in some ill patients, which were kind of interesting. Uh, and they saw some reduction [00:43:00] actually quite a large, a small study, quite a large reduction in diarrhea events among HIV patients in Uganda. So there's a few pieces here of kind of yeah, potentially interesting outcomes, but it's, I wouldn't say it's overwhelming.

Perry: [00:43:18] Yeah. Um, it is, it's definitely not. And there's studies that don't show improvements in diarrhea. They did a study of kids with Shigella infection, which is an unpleasant bacterial diarrhea illness and no difference with the colostrum. Um, we need to talk about safety because upfront that guy was holding if you're, if you're watching this on a video, this big jar of bovine colostrum, raw and unpasteurized.

Emily: [00:43:49] And I will say the reason the influencers like unpasteurized colostrum is that there are some elements of colostrum that would be killed by pasteurization, like some of these elements that might be killed by pasteurization. So if you're a true [00:44:00] wellness influencer, here you are into the raw colostrum. Although I will say all of these studies would be using pasteurized colostrum powder, which is in the study. Okay.

Perry: [00:44:12] Correct. Um, and moreover, even the things that are hurt by pasteurization, even the things that are inactivated by pasteurization still don't make it into your blood in the, in the raw form. So yeah.

Emily: [00:44:25] We're already over that. Okay.

Perry: [00:44:26] And what Emily, what else is killed by pasteurization?

Emily: [00:44:31] Yeah, it's it's E coli and other bacteria that make you really sick. And the reason that we don't recommend people drink raw milk or raw colostrum is that it can be and often is tremendously full of bacteria that will make you very sick. And if you are taking this colostrum so you don't have a lot of diarrhea, you are also putting yourself at risk for quite a lot of diarrhea from the E coli that may be lurking in your colostrum, and also other things, [00:45:00] not just E coli. Other things.

Perry: [00:45:01] Yep. I'll put some numbers on it for you. Journal of Dairy Science 2021. They looked at 1241 colostrum samples from 39 Czech dairy farms. The average count of bacteria per plate that they put the colostrum on was 408,000 colony forming units per milliliter, and only 28.4% met the recommended threshold for bacteria levels, which is less than 100,000 colony forming units per milliliter. A study in Northern Ireland a few years earlier than that found that 81% of raw colostrum samples exceeded industry bacterial contamination guidelines. So chances are there's quite a bit of E coli and other nasties in the colostrum if it hasn't been pasteurized.

Emily: [00:45:53] Yeah. There is some evidence that we also have some of these in the dried commercial products as well. [00:46:00] So it's not it's not only the raw milk colostrums that are impacted. Anyway, this is you should be careful about your colostrum.

Perry: [00:46:08] Definitely. Do you want to touch briefly, Emily on like this might be the bleeding heart in me here, but like, what about these baby cows? Like isn't it for them?

Emily: [00:46:21] It is for them. Uh, I mean, I think what the people who produce bovine colostrum will say is that an individual cow produces far more colostrum than a calf needs. I think the counter point is like, but why? That's not how evolution works. Um, you know, why are they producing all this extra colostrum? So I this definitely comes up in people's concerns. Um, I again, I think you make the same complaint about milk.

Perry: [00:46:50] I wouldn't though because milk, as long as you keep milking a cow they'll keep making milk even after the calf doesn't drink.

Emily: [00:46:56] Colostrum is more limited right?

Perry: [00:46:57] Yeah. Colostrum is like time limited. Yeah. [00:47:00] And think of how cute the baby cows are. Are you considering that aspect from a data point of view?

Emily: [00:47:07] I'm considering it, but I'm also thinking people, probably the people who are eating the raw colostrum are also eating veal.

Perry: [00:47:14] You think so? I feel like that Venn diagram does not overlap.

Emily: [00:47:17] I think you're wrong. I think you are wrong. But I guess we could look at the data.

Perry: [00:47:23] Listeners, are you both veal and raw colostrum?

Emily: [00:47:26] Okay. Uh. All right, Perry, smash or pass on colostrum?

Perry: [00:47:32] I am a pass on colostrum. I think, you know, if this is not the way I want to spend my 50 bucks a month and what I want to be, you know, mixing into my shakes in the morning, there's other better stuff. I'm a pass. How about you, Emily? Smash or pass?

Emily: [00:47:48] Okay, I, I am actually a soft smash and I will say I do have this. I do have.

Perry: [00:47:55] After all.

Emily: [00:47:55] This, after all this, I this is an example of something [00:48:00] where I think if you are an athlete who has GI problems, I believe this might be worth a self-experimentation. Okay. Because I think some of the evidence is a little suggestive. I wouldn't recommend it as a general rule, but I'm. I guess I'm soft, soft smash.

Perry: [00:48:23] Okay, I'll give it to you. Um, are you an athlete with GI problems? And do you feel like it's helped your athleticism or GI problem?

Emily: [00:48:31] Yes, I am an athlete with GI problems and no, I don't think that it helped me, but I am not sorry that I tried it. Okay, it turns out what helps is not eating too much salad for dinner.

Perry: [00:48:45] Mhm.

Emily: [00:48:46] We can get into that in another at another time. Or perhaps never. Perhaps we can never get into that.

Perry: [00:48:51] Um, well, not eating salad is cheaper than buying colostrum.

Emily: [00:48:57] Totally. Totally. Salad has too much fiber. That's [00:49:00] the problem anyway. There we go. Uh. All right, that is it for colostrum. Your mailbox. Question of the week after the break.

Speaker 5: [00:49:13] Hi, dad. Et al. Uh, this is Elia. Why do people sneeze when they look at the sun?

Perry: [00:49:18] This is a question from my own home. That's my daughter writing the question. This happens to her. Emily, are you a photic sneezer, which is the term?

Emily: [00:49:28] I'm not a photic sneeze. Or are you? Is it genetic?

Perry: [00:49:31] Uh, I am not, but my wife is. Um, and there is in fact a genetic condition called autosomal dominant compelling helio ophthalmic outburst or the achoo syndrome.

Emily: [00:49:48] Which you made that up.

Perry: [00:49:50] I did not. I mean, it is a it's a real genetic syndrome. That's maybe a bit more dramatic than what people are thinking about. These are people who will have [00:50:00] a series of like ten sneezes in response to bright light, which is not what, um, like my daughter or my wife has. I, you know, what most people have experienced is going into bright light and you have like a sneeze or two. This has been recognized for centuries and centuries. I think like, I think like Aristotle or something like this wrote about it and it's not fully understood. People think that it is a little cross-talk between your optic nerve and your ophthalmic nerve. So the nerves from your eyes and the nerve coming from your nose. And like the bright light, kind of like your optic nerve a little bit, and that kind of jazzes your ophthalmic nerve in some people and you just like sneeze out of confusion.

Emily: [00:50:42] That is totally fascinating. And so it's autosomal dominant, which means that it is strong. That would be a strong genetic link.

Perry: [00:50:50] Yeah. It would mean that if one of your parents has it, you have a 50% chance of inheriting it.

Emily: [00:50:56] That is totally fascinating. And I had no idea. The only thing that [00:51:00] makes me sneeze is pollen.

Perry: [00:51:01] Oh well, it's been it's been rough this year.

Emily: [00:51:04] It's been it's been a bad year for sneezing. Um. Achoo syndrome. Fantastic. All right. That is it for us today. Stick with us next week when we will ask what's the deal with psychedelics? I'm excited. But I will say I don't have these in my cabinet, Perry, so I won't have as much personal experience. Wellness, Actually is produced in association with iHeartMedia. Our senior producer is Tamar Avishai. Our executive producer at iHeart is Jennifer Bassett. Our theme music is by Eric Deutsch and our content is for educational purposes only.

Perry: [00:51:43] If you like the show, help other people find us. Leave a rating and review on Apple Podcasts or your podcatcher of choice and help us spread the word about the show. You can follow us on Instagram at pod. And don't forget, we want to hear from you. Head over to wellness.fm [00:52:00] and leave us a question for our mailbag or suggest a topic for a future show.

Emily: [00:52:04] We'll let the influencers have the last word.

Influencer: [00:52:06] How to know if you have a leaky gut?

Dr. Mike: [00:52:08] There's no such thing.

Influencer: [00:52:09] One chronic fatigue.

Dr. Mike: [00:52:10] I have chronic fatigue.

Influencer: [00:52:11] Frequent headaches, and brain fog.

Dr. Mike: [00:52:13] I have frequent headaches and brain fog.

Influencer: [00:52:15] Colostrum is a.

Dr. Mike: [00:52:16] Pure. Oh come on man.

Influencer: [00:52:17] Strengthens your gut barrier. Replenishes your microbiome. Combats bloating, constipation...