This episode of Science Versus investigates the health claims and risks of drinking raw milk. Host Wendy Zuckerman embarks on a "grey area" mission to purchase raw milk, which is often sold as pet food due to legal restrictions. The debate centers on whether raw milk offers unique benefits, such as improved gut health, reduced allergies, and asthma prevention, or if it poses serious health dangers.
Scientists, including food science professor John Lucy, explain that raw milk from healthy cows initially contains few bacteria, undermining claims that it is a probiotic powerhouse. The idea that raw milk prevents allergies and asthma stems from studies on farm children, but research suggests that exposure to animals and barn environments—not milk consumption—is the likely protective factor. Additionally, many European studies compared raw milk to highly processed, shelf-stable milk, not standard pasteurized milk.
The risks of raw milk are significant. Contamination can occur from cow feces, soil, or bedding, introducing pathogens like Listeria, Salmonella, and E. coli. Studies show that 20-30% of bulk tank samples contain at least one pathogen, and raw milk is responsible for 96% of dairy-related illnesses. Outbreaks have hospitalized children and even caused pregnancy loss. While raw milk consumption is not always dangerous, experts conclude that pasteurization is a crucial safety measure, and the purported benefits do not outweigh the risks. Wendy ultimately decides not to drink the milk.
Hi, I'm Wendy Zuckerman, and this is Science Verses.
After this episode, we're taking a quick break just to work on some future episodes.
So if you have ideas, let us know in the comments, things you'd like us to versus.
And we wanted to let you know that we now have a YouTube channel.
Yay!
It's Science VS Podcast.
There's a link in the show notes.
You could also catch us on Instagram, TikTok.
But now it's time for the episode.
Let's jump in.
I'm on an illegal mission today.
Legal grey area would be more accurate, but for a cold open like this, we're going to say illegal.
No, we're going to say grey area.
There's no way that would get through fact check.
The point is I'm doing something naughty.
A couple of weeks ago, I went on a secret mission.
Okay.
Here I go.
I'm going into the store.
There's plants out the front, plants inside, organic bananas to my left.
I'm here to buy something that some say is dangerous and could even kill me.
The chocolate milk drops.
I bet there's carob somewhere around here.
God only knows.
Oh my gosh, there's an empty, it's a completely empty fridge.
Fridge.
There's one left.
One left.
I found it.
It's a white substance in a plastic bottle.
There's one left.
There's one left.
One raw milk.
Raw milk.
I've got it.
I've got it.
I've got it.
Okay.
But should I drink it?
Thank you.
The cup?
Yes, please.
Sure.
A lot of people online are saying, yes, that this milk that I've got that hasn't been pasteurized
and it's straight from the teat has heaps of benefits.
They say, just look at the science.
Raw milk, raw dairy in your diet is definitely going to improve your health.
Raw milk protects kids from asthma, eczema, and allergies.
It is packed full of gut-healthy bacteria.
You heal your microbiome.
God intended milk to be raw.
If he didn't, he would have put a pasteurizer.
He would have put a pasteurization chamber on the udder of a cow.
Raw milk fandom has even hit the udder echelons of society.
Health and Human Services Secretary Robert F. Kennedy Jr. is a huge raw milk fan.
And it's not just the RFK Juniors of the world.
It's pretty common to drink raw milk in some countries.
You can even find it in some vending machines around Europe.
But of course, there is a flip side to this story.
The raw milk naysayers.
Who reckon that raw milk is dangerous.
It's actually illegal to sell raw milk for humans to drink in Australia and in some states in the U.S. as well.
I had to find it in the pet food section of the store.
So why are people worried here?
Some people keep trying to act like drinking raw milk is unlocking some secret level of health.
Well, I want to say congratulations.
It unlocked diarrhea, fever, stomach cramps, nausea.
And vomiting.
The only reason to drink raw milk is if you ever wondered, "Hey, I wonder what it's like to die from having too much diarrhea."
So who's right here?
Could drinking raw milk be the thing you need to help your microbiome, your allergies, your asthma?
Or are you going to die from having too much diarrhea?
Today on the show, we're going to squeeze the teat of science until we've filled our bucket with facts around raw milk.
Because, you know, there's a lot of God intended milk to be raw.
And then there's science.
Science versus raw milk is coming up just after the break.
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Welcome back.
Today we are guzzling down the science of raw milk.
And I'm here with our editor, Blythe Terrell.
Hello, Blythe.
Hello, Wendy.
So I've got it in my hot little hands.
Ooh, I'm so nervous.
I should say, so it says pet milk only.
And what's funny about the health food store that I bought it at is
so you go to the milk section with the regular pasteurized milk
and then they have a sign that says,
if you want raw milk, go to the pet food section.
But there is no other pet food sold.
In the quote unquote pet food section across the store,
there's just a fridge with raw milk and that's it.
Wow, that is cheeky.
Yeah.
Okay, so let's open, let's open this raw milk.
Once it's open, it's open, Wendy.
Then it really becomes like Chekhov's raw milk.
Yeah.
Okay, here we go.
There it is.
So you're just going to put it there next to you, right?
You're not having it now.
Nope.
The question is, Blythe, am I going to drink this?
It sounds like maybe you need some science before you can make that call.
I believe so.
So tell me, Blythe, let's start here.
What is different about this raw milk
compared to regular milk that you would buy at the store?
Okay, so the key difference is that it has not been pasteurized.
Right?
And I can tell you a little bit about pasteurization.
Thank you.
So what we do when we pasteurize milk
is basically we heat it up usually to 161 degrees Fahrenheit,
72 degrees Celsius.
Thank you.
For you and those like you.
For like 15 seconds or less.
And when we started doing this at scale,
it was about 100 years ago.
Okay.
And that, Wendy, was partly because milk was making people sick.
Actually, a lot of the time with things like tuberculosis,
Like the cows would get tuberculosis.
Oh.
And like it would come out in their milk and people would drink the milk and get TB.
Wow.
Oh, I didn't realize TB.
Okay.
So they start pasteurizing the milk and it works.
It kills the bugs.
Kills the TB.
Yes.
It becomes the thing we do in the U.S., right?
And in a lot of other places.
And so I guess now the movement is saying we're killing too much in the milk.
Right.
Perhaps it's overkill.
Mm-hmm.
Overkill.
Like a big argument is that we're getting rid of microbes that actually like would make
our guts stronger if they hung around.
Right.
We're getting rid of the bad microbes and the good.
And that's where I want to start with this argument about the microbiome.
And so to find out if that is true, I called up this guy in the dairy capital of the United States.
My name is John Lucy.
I'm a professor.
I'm a professor in the food science department here at the University of Wisconsin-Madison.
And I'm also the director of our Center for Dairy Research.
And that is not all.
John is from Ireland.
And also. I grew up on a farm, too.
So a dairy farm as well.
And I also worked for a couple of years in New Zealand, another dairy country.
So, Wendy, I brought you the Dairy King.
Yeah, he's perfect.
He's perfect.
And so I asked John about this argument that raw milk is good for your gut.
That it's kind of a probiotic, basically.
Yeah.
And so John told me out of the gate that there is a really good reason to be skeptical of this.
And it comes down to the fact that generally, if you've got a healthy cow,
the milk doesn't pop out of the teat chock full of bacteria.
There's very little bugs of any description, good, bad, or indifferent, in milk.
That's where the science is right now.
It's not that there's a really important. And good bacteria, flora in the raw milk.
That's just not where we're at right now.
Just the science isn't supportive of it.
That's interesting, though, because it definitely suggests that this raw milk in front of me isn't that dangerous.
Right?
We're going to get into the details of that later.
Okay.
But, like, basically, the scientists tend to agree that when it comes out initially, like, it doesn't really have a bunch of bacteria in it.
And this actually makes intuitive sense.
Because if you think about, like, the dairy that we eat. that we know has good probiotic stuff in it, like yogurt.
That stuff is fermented, which means that you've added that bacteria to it.
Of course.
You're thinking about yogurt, kefir, things like that.
Yeah.
And even if there were like a tiny bit of good gut bugs for the microbiome,
it wouldn't be there in the amount that it would need to be
in order to actually do anything inside your gut.
Yeah.
Because for a probiotic to work,
scientists generally think that like it has to have a lot of these bugs.
Here is John on that.
So if you like buy a probiotic supplement and you look at the fine print,
they'll say it contains per gram millions and billions and whatever of bugs.
And because numbers are important for these benefits,
it's not like because your own gut microbiome is in the bazillions, you know,
off the chart.
Yeah.
The analogy that I always hear from researchers talking about the microbiome
is that if you imagine your gut like a rainforest
and then you drink some milk and say it's like a pigeon comes in to the rainforest,
it's not going to change things.
It's not going to flourish.
Right, right.
That space is taken, right?
Well, exactly.
So you can't just like sprinkle in a few things and expect to like fix your, your shit.
Literally.
Literally.
Right.
So John actually told me that to do,
the kind of thing that people are claiming that the milk could do.
The milk would need a million per gram of bugs.
And there's, if the milk had a million per gram of any bugs,
it would already start to be sour.
Oh, of anything.
Anything.
So to me, this, this is what makes the microbiome claim fall pretty flat.
Like it does not make me want to go running to the local farm
for a warm frothy glass fresh from the udder.
All right.
So the next claim let's look up is this idea that it can prevent allergies and asthma.
Yes.
Anything to this?
This one, Wendy, is like a lot more interesting, actually.
Ooh.
This is the one that made me go, hmm.
Hmm.
Hmm.
All right.
Can you hear the intrigue?
Let's get it, Flav.
Yeah.
Yes.
This is a big one that people say.
Right.
They say that if you give kids raw milk, it can help prevent allergy,
it can help prevent asthma.
And actually, if raw milk could do this, it would actually be a pretty big deal.
Because these conditions, asthma and allergies, they're super common in kids.
I talked about this with Professor Christine Cerugy.
She's a pediatric allergist and immunologist who's also at the University of Wisconsin.
And she says asthma can be really serious.
It is the number one reason for admission to the hospital.
For a child.
Asthma and we. Really?
The number one reason?
Exactly.
And so if you can prevent it in the first place from developing, that's game-changing.
Yeah.
And we've seen a rise in allergies and asthma in kids, right?
Yes.
And that's what she pointed out, too, is that, like, in a lot of countries, these numbers are going up.
So this all is connected to raw milk because a couple of decades ago,
we started getting studies relating to asthma and allergies in this particular group.
Kids who live on farms.
So what these studies would do is that a lot of times there were these big surveys coming out of Europe,
and they would look at thousands of kids, comparing the health of the farm kids,
medical conditions they had to kids who didn't live on the farm.
And what they found was. Really striking epidemiologic evidence that the children growing up on farms
are really protected from developing allergic diseases.
Some people say the farm effect.
One study out of Austria found that about 1% of the farm kids had asthma
compared to about 4% of kids who didn't live on the farm.
You know, a study out of Germany found that just over 3% of farm kids had asthma
compared to more than 6% of non-farm kids.
Yeah.
It's more than allergies and asthma.
It's, like, skin conditions, stuff like eczema, these histamine things.
Yeah.
And Christine told me this finding.
It's been borne out in the U.S. as well.
I feel like this story of kids on farms. Farms having low allergies, it's sort of. I feel like the science has known this for a while,
but it's had in the past been attributed to the hygiene hypothesis
and that maybe these kids on farms are exposed to more dirt
and that's really good for them and lowering their risk of getting these illnesses
is now the thought moving maybe it's because they're drinking raw milk?
You have entered the ring.
You have entered the ring on this debate, Wendy.
So, do you want to walk me through. So, with the hygiene hypothesis, let's. Bing, bing, bing, bing, bing.
So, okay.
So, what is the up-to-date thinking on that?
The up-to-date thinking is that, yes, like, these exposures to things on the farm,
to, like, dust, to dander, all these things that challenge your immune system
at a really young age and sort of teach your immune system, like,
what's out in the world and basically strengthens it.
So that, like, when it encounters that stuff later,
you don't have a big allergic reaction to it.
The idea is still that that's important.
But at the same time, some scientists have also looked closer
and started to think that maybe also the milk that these farm kids are drinking is at play.
Okay.
And some of these, particularly some of these researchers out of Europe,
started thinking this because they looked at these,
they did these big observational studies of a lot of kids
and they tried. They tried to look at kids who were, in some cases,
not living on the farm, but who were drinking raw milk.
And they tried to control for some of those other exposures on the farm.
And they have started to say,
we think that there is something going on with the milk.
Like, we don't, we think that the hygiene hypothesis is part of this,
but we also think that the milk is at play.
This will just show my ignorance.
Living on a farm, growing up on a farm,
these kids are drinking raw milk.
I feel like we're making some assumptions here.
I'm guessing the researchers actually asked these families.
Wendy, you're such a good student of the challenges of this research.
How did you know?
Wait, is this an actual question?
Yeah, yeah, it is.
So, it is not always clear that the stuff that the kids are drinking on the farm
is strictly raw milk.
Because some of the time, even if kids are drinking milk from the farm,
it's getting boiled, it's getting treated some kind of way.
And the studies don't always. They don't always check for that.
And then, on top of that,
some of these studies coming out of Europe
are comparing this farm milk
to milk that has gone way beyond
sort of standard pasteurization.
So, this is stuff that, like,
has been heated up way higher to a way higher temperature.
And that kind of milk is more common in Europe.
It's actually, like, the milk that you get
that you don't have to put in the fridge,
like the shelf-stable stuff.
Oh, like the crap you get on a plane.
Right.
Like, sterilized.
That's sitting in a hotel room in a little box.
That sort of stuff.
Exactly.
That can just sit on the shelf for three months or whatever
without being refrigerated.
Oh, so you compare it to that,
which is seriously processed milk.
Right.
And so, online,
this is what a lot of people seem to get wrong about these studies.
You know, they're assuming that, like, farm milk is raw milk.
But if you actually read the nitty-gritty papers,
you see sometimes that's not true.
And sometimes what they're looking at is something else,
Wendy,
called, quote,
minimally processed milk.
You want to know what that is?
Yeah, minimally processed milk.
What's that?
So that is
pasteurized milk.
That's that science versus touch flight,
getting into the papers,
working out what all the definitions are.
That's right.
We love a definition.
That's why we're here.
And so I will say, despite all that,
scientists like Christine,
they are not, like, driving a nail
through the coffin of this claim
that raw milk might,
do something to help reduce allergies.
So when she looks at all this complexity,
she's like,
I'm not
crying over spilt milk.
Correct.
She doesn't think the science is spoiled.
She thinks we shouldn't be lapping up
the science out of Europe
and using it
to bolster
claims that raw milk is good for you.
But she doesn't think
we're ready
for a milk crisis.
She doesn't think that we should all
drink raw milk, shake up,
and that we should all be drinking
raw milk right now.
She does not think that.
So we've done our puns.
Where do we go from here, then?
Well, I'm not going to leave you
with just that.
Okay.
Okay.
Because. It would behoove you to tell me more.
Um, I can. Sorry, sorry, sorry.
I can squeeze out a few more drops of science.
Uh, just. Okay.
Okay.
Okay.
We've really milked this
for all it's worth.
Oh, my God.
I'm going to put my dipper
back into the pail, Wendy,
and pull out more science for you.
Okay.
So, Christine actually
was part of a study
that I did think
does some work here
to help us parse out
how big of a deal
raw milk might be.
Like, if there's a signal,
how much might that matter
compared to, like,
the other stuff people
are exposed to on the farm.
Right?
And so, Christine
is based in Wisconsin.
and she works with a lot of people
She studies a lot of different families who live on farms.
And what she did is some research into these two particular groups in the U.S.
The Amish and the Old Order Mennonites.
Are you familiar?
Yeah, I've been to Pennsylvania, intercourse, big Amish community there.
My parents laughed a lot at the name.
I didn't understand why it was funny.
I do now.
Tell me more.
So, yes, so the Amish and the Old Order Mennonites are similar in a lot of ways.
They often have big families.
They live these, like, sort of more traditional farming lifestyles.
Not big on technology a lot of the time.
Yeah.
And they tend to drink raw milk.
Okay, great.
And farm from the farm.
Yes, great.
Raw milk.
Perfect.
Yes.
Yes.
But these two groups are different in one important way.
So the Amish often don't use any electricity at all.
And the Mennonites, some of them do have electricity.
So they tend to sometimes use mechanized processes for things.
Mm-hmm, mm-hmm.
So Christine's team, what they did is that they surveyed a bunch of families in these two groups.
They looked at the rates of asthma, the rates of allergy, and they found. The Amish community is, like, super protected.
Like, they had decreased allergic diseases across the board compared to the Old Order Mennonites.
This might suggest that what matters. This might suggest that what matters here is that they're doing all this stuff by hand with the animals.
So that animal contact is what's important.
So what you see in, like, an Amish family, and I'm speaking generally here, right, is that people are in the barn, you know?
They're, like, one-on-one.
They're milking the cows by hand.
They're in the cow shed.
It's not about drinking the raw milk.
It's about all that time with the animals.
That is a suggestion that the time with the animals could be more important.
Which is back to the hygiene hypothesis.
That's bing, bing, bing.
Exactly.
Hygiene hypothesis.
Bing, bing, bing.
Yes.
Yes.
Another scientist told me that in Amish households, a lot of times it's the women who are doing the milking.
So they're in the barns a lot, including when they're pregnant, maybe including when they have really small babies, you know, and that the kids are involved.
And so there's, like, just a lot of exposure one-on-one with animals that if you have, like, a mechanical milking setup,
or, like, a more mechanized farm, you're on the tractors, all this stuff, you're just, like, not up in it with the animals nearly as much.
Got it.
And the thinking is that that might be, we don't know for sure, but that might be the bigger difference maker here.
Mm-hmm.
So, like, even away from the Amish and the Mennonites, just sort of bigger picture, you know, Christine's group, they study a lot of farming families in Wisconsin.
And they will ask them,
You know, is the child going into the barn?
And if so, at what age?
Yeah.
Yeah.
Yeah.
Yeah.
Yeah.
Yeah.
I mean, that makes a difference.
And getting exposed to that barn environment in the stable, like, that is another protective signal.
At what age is it most beneficial for the kid to be in the barn?
Yeah.
I mean, it's a good question.
The data from the epidemiologic studies strongly suggests that this needs to happen early in life.
And the European studies have suggested that.
Even begins in utero.
Uh-huh.
So, actually, what we need to be doing is taking our kids to the farm or going to farms when pregnant to reduce the risk of allergies and asthma.
That's where we're at.
Yeah, which is sort of a little bit of an annoying answer, right?
Like, because not everybody has access to that kind of thing.
But the other thing Christine told me is that, like, get a pet, get a dog.
Like, that also is a good way.
That's a good way for your kid to be exposed to this type of stuff early in life.
So, where we're at with the research at the moment, this raw milk in front of me, not packed with good bacteria,
and probably not going to be the thing to help me with my allergies or reduce your kid's chance of having eczema, allergies, and asthma.
Is that where we're at?
I think that's right.
Um, you know, it's possible there's some kind of link with allergies and asthma.
Not really a slam dunk.
Okay.
How are you feeling about the idea of taking a big old gulp of that?
I mean, less interested than when we started, I've got to say.
But I'm also less worried about it because John said there's probably not that many bad bugs in here.
But is that. Uh-huh.
Ah.
Ah.
Ha, ha, ha, ah.
Ah.
I'm going to have to stop you right there.
Oh, okay.
Let's talk about that after the break.
After the break.
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All right, welcome back.
I'm here with Blythe.
We are suckling at the teat of raw milk research.
Absolutely.
Yes, we are.
Okay, so now we are on to the research.
How dangerous is this glass of milk in front of me?
Because I am getting thirsty, Blythe.
I know, my time is running out.
I'm parched, I'm parched.
Right, okay, let me tell you, even though, like John said, the milk doesn't start out with a bunch of bugs in it if the cow is healthy, of course, sometimes the cow is not healthy and gnarly stuff can get into the milk that way.
So, actually, astute listeners of the show will remember from our bird flu episode that cows,
cows can get bird flu and that can get into their milk.
Yes, that's right.
But even if the cow is healthy, you have something else to worry about because the other big concern is that even if the milk comes out okay, it can get contaminated afterward.
Bugs can get in because cows are on farms and the milk comes out of their udders, which are just kind of like flopping around under their bodies.
It's also somewhat close to their butthole, right?
I guess.
Yes, near the poop chute.
Yes.
So, they can come into contact with all sorts of stuff and I dug into this with John Lucy, who's the first scientist that we heard from.
You know, I grew up in a farm, we do the best we can, but you try and keep it as clean as you can, but to think that the ground or the soil or the bedding that the animal is laying down in is sterile is just fantasy and the problem is the dairy farms are just not a sterile environment.
Right, you can't, the cow's not in a bubble.
The cow's not in a bubble, the soil is not in a bubble, the feed is not in a bubble.
That's right.
That's fascinating. So the, so it comes out, let's say close to sterile, but as soon
as it's out, then it's exposed to all of these other things and that stuff that can then infect
the milk that tends to be the bad bacteria. Is that right? Yes, exactly. Like that's what we,
that's what we see. It's a dirt, it's a dirty environment because there's dirt, you know,
and actually one thing that John told me that was also kind of interesting
is that if this bacteria gets on the teat of the cow somehow, sometimes it just like hangs out
there. We all see these hospital shows and we see the doctor about to go into the surgery
and he's washing his hands and it's not a five second job. It's like scrubbing of the hands,
scrubbing, scrubbing, scrubbing. Why? Because on the hands, they can be bacteria
and it can form actually biofilms on the hands and in the environment. And that means it's harder
to remove than just.
a simple little wash off. The same can be true on the outside of these other, of the teats that the
cow has. They can actually be permanent bacteria living on the outside of it that are very hard
to remove. And remember, this is a sensitive area for the cow too, so you can't spend five minutes
like the doctor scrubbing. And the things we're worried about here are stuff like salmonella,
E. coli, this thing called Campylobacter. And in particular, I want to zoom in on one
bacteria, Listeria. So there's a bunch of different types of Listeria, but one of them
in particular can make us pretty sick. And it can cause gross stuff like diarrhea and nausea,
but it's actually especially dangerous to people with compromised immune systems.
And if you're pregnant, it can kill the baby. And Listeria is kind of all over the farm. You
can find it all over the farm. You can find it in the cows a lot of the time, at least in their crap. Here's John again.
I'll give you just an example. One of my colleagues here at the University of Wisconsin
did a study of a farm here in Wisconsin, and she literally went out and sampled poop from
these animals and cows. 90% of the animals were carrying Listeria monocytogenes.
So that's in their poo though. So then the question is,
how often is that Listeria, any of these scary bugs going from the farm to the milk, right?
Right.
That's the question.
That is the question. How often is this grotty stuff actually getting
into the milk?
Yes, yes.
And so one way that scientists try to figure this out is that they look at the milk at the dairy,
because it comes out of the cows, it all gets collected up before it gets pasteurized, right?
Yeah.
And what happens is it gets collected in this big tank called,
a bulk tank.
Okay.
And scientists, what they'll do is they'll take samples from a bunch of tanks,
and they'll actually analyze them to see what's in there.
I would say, you know, if you look at the percentage of the different pathogens,
sometimes you see 5% of them are contaminated with Listeria, 5% are contaminated, roughly,
I'm giving broad ranges, with Campylobacter, E. coli, et cetera.
Yeah. So when they look at these samples, about 1 in 20 of them have one of these,
nasty bacteria inside them.
But if you amalgamate all of them, and you ask a slightly different question,
John, how many bulk tanks in many of these surveys have at least one pathogen?
Mm-hmm.
Sometimes it's as high as 20 to 30% have one pathogen present in the bulk tank.
Whoa.
Whoa, there's no way I'm drinking that!
You don't like those odds?
No way!
At the upper estimate of 30%?
At the upper estimate of 30% in the bulk tanks?
Yeah.
Whoa! And why would you give that to your pet?
Or your kid, Wendy.
Right.
So, I mean, the bottom line is, like, it's pretty common to find creepy stuff in the milk.
Like, John talked about those numbers.
I found a study out of the UK that looked at raw milk that was actually for sale,
and it found that 40% of the samples they looked at had some kind of problem with a risky pathogen.
But then, 40, right, but then. Not everyone who will then drink these microbes in their raw milk will then get sick, right?
Some of them, their immune system will deal with it.
So, how often are people getting sick from drinking raw milk?
Yeah. I mean, it's a great question.
You know, because, like, look, some people drink raw milk and they are totally fine.
You know, it's not like they're drinking arsenic, right?
But there have definitely been some disease outbreaks.
So, this one CDC study looked at about a 20-year period
and found more than 200 outbreaks tied to raw milk in the U.S.,
getting about 2,600 people sick.
Just this year, there have been a couple of outbreaks in the headlines.
There was an E. coli outbreak that was linked to this raw cheese.
In Idaho, almost 60 people got sick from raw milk, a bunch of them from Campylobacter.
And look, when you look at the raw numbers, Wendy. Yeah.
Yes, nice.
People are more likely to get sick from other foods.
Stuff like seafood, maybe leafy vegetables like spinach.
That is true.
Uh-huh.
But with raw milk, what freaks out scientists like John
is that a lot of the time with these outbreaks, the people who get sick are kids.
Children end up being the most largest percentage of hospitalizations for raw milk outbreaks.
They don't have a choice. They don't know anything.
They've been put, mom and dad are feeding it to their kids.
Yes.
Those. Those are the ones that I get most concerned about.
And depending on which study you take, sometimes it's like a quarter or more,
or sometimes under the age of three and five years old.
Like, people are thinking, oh, I've got to expose my kids to pathogens.
Are you serious?
They could end up in hospital?
That's the problem.
And earlier this year, this is actually how raw milk kind of got on my radar,
because there was a listeria case.
So this woman in New Mexico. Apparently drank raw milk during her pregnancy, and she lost her baby.
Because of a listeria infection. She had a listeria infection.
Yeah.
Oh, God.
So, like, not common from what we can tell, but these outbreaks, when they happen, people can die.
I mean, this is exactly why it's so devastating, right?
I mean, I don't know what was happening for this woman during her pregnancy, but more broadly,
you see these trends and these influences and people saying,
damn the establishment, what do they know?
Raw milk is the answer.
Pasteurization is a farce.
And then this is the ultimate conclusion.
Of course it is.
Then people thinking, oh, I've got to be drinking raw milk to help my unborn child
and reduce the chance of them getting allergies,
and then they're missing the bigger picture that is listeria.
Right.
And the stakes are just really high.
If. Because it's not common for those horrible, horrible things to happen, but when they do. It's awful.
They're awful.
Yeah.
Yeah.
I just want to. Just want to spill that milk right in front of me.
But this carpet, I don't want to have to clean that.
So, I mean, it's really feeling like this raw milk. This raw milk's not coming back from that, right?
No, I don't think so.
And I mean, you know, just to say, like, some raw milk producers, of course, they'll say, like, listen,
we try to avoid this.
We keep things clean.
We try to test for bacteria.
And also, like, there are instances where stuff sneaks into pasteurized milk and makes you sick.
Right.
But one study found that when people were getting sick from contaminated dairy,
96% of the time, it was the raw stuff.
Wow.
Okay.
Yeah, yeah, yeah.
96% of the time.
Which is why we pasteurize it.
Pasteurization works really well to kill all the stuff that we are talking about.
You had it fast in 2026.
A hundred plus years later.
Pasteurization works really well.
Yeah.
I mean, listen, John was like, it's good that we've been doing it so long.
You know, like, it's allowed us to, like, test it and refine it and figure out systems for it.
Figure out how to do it at scale.
And all of that has been put in place over 100 years to show that pasteurized milk is,
you know, one of the safest food products on the planet.
So I asked him,
Is there a way to have safe raw milk?
You're shaking your head.
No, no.
It's a foolish and risky thing to do.
I don't want to be called foolish by John.
So what are you going to do with that milk?
I mean, there's this annoying neighborhood cat.
Wendy, no.
That might be thirsty and pisses on my security gate.
If you even.
Don't do it.
It says pet milk only.
Oh, my God, Wendy.
Throw it out.
Put it down the drain.
Tell us in the comments.
What should I do with the raw milk?
Oh, my God.
Yeah.
I think they'll tell you exactly where you can put it, Wendy.
That's science versus.
I'm not going to give it to the cat.
Don't call Peter.
I know, you would never.
Don't go.
Put down the phone.
Don't call Peter.
It's fine.
How many citations are in this week's episode?
There are 72 citations in this week's episode.
And if people want to see them, where should they go?
They can find a link to our transcript in our show notes.
Thank you, Blythe.
Like I mentioned, we just started a YouTube channel.
So you can come and find us at Science VS Podcast.
That's where we are.
There's going to be a link in the show notes.
And while you are looking at the transcript, you can click on it.
And find us there, see some of our video episodes.
And Blythe, like I said at the start of the show, we are taking a short break.
Yeah, just a few weeks.
We'll be back.
In a few weeks.
All right.
Bye.
Bye.
This episode was produced by Blythe Terrell
with help from Makedi Foster-Keys,
Meryl Horne, Rose Rimler, Michelle Dang
and me, Wendy Zuckerman.
We're edited by Blythe Terrell.
I'm the executive producer.
Fact-checking by Diane Kelly.
Research help from Erica Akiko Howard.
Mix and sound design 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 Professor Marcus Egger.
Thank you so much for your time.
Thanks to Elsevier for sharing your raw milk book with us.
Thanks to the Zuckerman family,
Joseph LaBelle Wilson and Jack Weinstein.
I'm Wendy Zuckerman.
Back to you next time.
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Podcast Summary
Key Points:
Raw milk is unpasteurized and has not undergone heat treatment to kill bacteria.
Proponents claim raw milk benefits gut health, allergies, and asthma, but scientists find weak evidence for these benefits.
Milk from healthy cows starts with few bacteria, but contamination can occur from farm environments, including pathogens like Salmonella, E. coli, Campylobacter, and Listeria.
Studies on farm kids and allergies suggest animal exposure, not raw milk, may be the protective factor.
Raw milk is linked to disease outbreaks, with children being especially vulnerable; pasteurization is highly effective at preventing illness.
Summary:
This episode of Science Versus investigates the health claims and risks of drinking raw milk. Host Wendy Zuckerman embarks on a "grey area" mission to purchase raw milk, which is often sold as pet food due to legal restrictions. The debate centers on whether raw milk offers unique benefits, such as improved gut health, reduced allergies, and asthma prevention, or if it poses serious health dangers.
Scientists, including food science professor John Lucy, explain that raw milk from healthy cows initially contains few bacteria, undermining claims that it is a probiotic powerhouse. The idea that raw milk prevents allergies and asthma stems from studies on farm children, but research suggests that exposure to animals and barn environments—not milk consumption—is the likely protective factor. Additionally, many European studies compared raw milk to highly processed, shelf-stable milk, not standard pasteurized milk.
The risks of raw milk are significant. Contamination can occur from cow feces, soil, or bedding, introducing pathogens like Listeria, Salmonella, and E. coli. Studies show that 20-30% of bulk tank samples contain at least one pathogen, and raw milk is responsible for 96% of dairy-related illnesses. Outbreaks have hospitalized children and even caused pregnancy loss. While raw milk consumption is not always dangerous, experts conclude that pasteurization is a crucial safety measure, and the purported benefits do not outweigh the risks. Wendy ultimately decides not to drink the milk.
FAQs
Raw milk is milk that has not been pasteurized, meaning it hasn't been heated to kill bacteria. It is sold directly from the cow, often in stores' pet food sections where legal.
No, the science doesn't support this claim. Healthy cow's milk comes out with very few bacteria, and it lacks the high numbers of beneficial microbes needed to affect your gut, unlike fermented foods like yogurt.
Studies show farm children have lower allergy and asthma rates, but this is likely due to early exposure to animals and barn environments, not raw milk. The evidence for raw milk's specific role is weak and inconclusive.
Raw milk can be contaminated with harmful bacteria like Salmonella, E. coli, Campylobacter, and Listeria. These can cause diarrhea, fever, nausea, and severe illness, especially in children, pregnant women, and people with weakened immune systems.
Outbreaks are relatively rare, but they do occur. A CDC study found over 200 outbreaks in the U.S. over 20 years, and contaminated raw milk causes 96% of dairy-related illnesses, with children often being hospitalized.
Yes, pasteurization kills harmful bacteria effectively. Pasteurized milk is considered one of the safest food products on the planet, having been refined and tested for over 100 years.
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