The Daily - The Sunday Read: ‘Some Raw Truths About Raw Milk’

Episode Date: February 9, 2025

Thousands of years ago, after domesticating cows and other ruminants, humans did something remarkable: They began to consume the milk from these animals.But living closely with animals and drinking their milk also presents risks, chief among them the increased likelihood that infections will jump from animals to people. Some of humanity’s nastiest scourges, including smallpox and measles, probably originated in domesticated animals. In the 19th century, health authorities began pushing for milk to be treated by heating it; this simple practice of pasteurizing milk would come to be considered one of the great public-health triumphs of the modern era.Today, however, a small but growing number of Americans prefer to drink their milk raw. And Robert F. Kennedy Jr., President Trump’s choice to lead the Department of Health and Human Services, now stands at the vanguard of this movement. Unlock full access to New York Times podcasts and explore everything from politics to pop culture. Subscribe today at nytimes.com/podcasts or on Apple Podcasts and Spotify.

Hi, my name is Moises Velazquez-Manoff, and I'm a contributor to the New York Times magazine. I'm a science writer, and I mostly cover health, medicine, and the environment. This week's Sunday Read is based on a recent magazine article of mine about raw milk. The first and most important takeaway of my piece is that raw milk can literally kill you and that people should make sure they understand the risks before drinking it. And even if it doesn't kill you, it can make you extremely sick. We're talking about ending up in the ICU potentially with kidney failure because of a terrible E. coli strain, just as one example. I grew up in New Mexico where some people were drinking raw milk because it fit into

their back to the land philosophy or because they liked the way it tasted. But nowadays, raw milk is just as much a beverage for libertarian types, homeschoolers, people who are suspicious of the government telling them what to do, and health fanatics looking for quote unquote superfoods. On social media, you may have caught some of the magical claims about raw milk. Like I started drinking it and my eczema went away. Or it cured my inflammatory problems. And those are some of the moderate

claims. There's no science behind raw milk curing anything. And yet, actually, there have been studies that suggest there's a value in terms of prevention. I once researched and wrote about something called the farm effect. Scientists have observed that rural kids in Europe and the US who grew up on farms have a relatively low risk of allergies and asthma. They think that raw milk contributes to this protective effect. And they think this because people who don't live on farms but who might get raw milk from a farm down the road also have a lower risk of allergies and asthma.

So how are we supposed to reconcile the possible health benefits of raw milk with the fact that it might also kill us? That's an important question. And so what I really wanted to do for today's episode is drill down into the science behind everything that's being said. Both the known good and the known bad and all the potentials about raw milk. I wanted to do this because I think we should be able to have a nuanced conversation. Because if scientists and science journalists could clearly explain how dangerous raw milk can be, while still

pointing out that yes there may be certain health benefits then maybe we can prevent people from going into the corners of the internet where the claims become outrageous and safety is overlooked with potentially deadly consequences. So here's my article, read by Anthony Ray Perez. Our producer today is Tali Aboukassas, and our music was written and performed by Aaron Esposito. Thanks for listening. Thousands of years ago, after domesticating cows and other ruminants, humans did something

remarkable. They began to consume the milk from these animals. Scientists consider mammalian milk to confer a tremendous evolutionary advantage because it allows mothers to feed immature offspring with food well tailored to their needs. With the advent of daring, humans inserted themselves into this ancient relationship between ruminant mothers and their offspring, diverting this source of nutrition into their own bodies. By consuming the milk of ruminants, possibly after fermenting it, humans found a reliable way to nourish themselves with grass and other tough plant material

that they themselves couldn't digest directly. As a cultural adaptation, daring was so important, one scientist told me, that whoever invented it deserves to win a Nobel Prize posthumously every year. But living closely with animals and drinking their milk also presents risks, chief among them the increased likelihood that infections will jump from animals to people. Some of humanity's nastiest scourges, including smallpox and measles, probably originated in domesticated animals. In the 19th century, as industrialization spurred urbanization and mass migration, milk

became a major vector of disease. As late as 1938, illnesses from milk still accounted for one-quarter of all infectious diseases contracted from what people ate and drank that year. During this period, newly established health authorities began pushing for milk to be treated by heating it. This simple practice of pasteurizing milk would come to be considered one of the great public health triumphs of the modern era. Today, however, a small but growing number of Americans prefer to drink their milk raw. And Robert F. Kennedy Jr., Donald Trump's choice to lead the Department of Health and Human Services, now stands at the vanguard of this movement.

Kennedy has said he drinks raw milk and has criticized what he describes as the Food and Drug Administration's aggressive suppression of raw milk production, among other things. Enthusiasts anticipate that as HHS secretary, he would make raw milk easier to acquire, although how remains unclear. Federal regulations prohibit the sale of raw milk across state lines, but where it's legal, raw milk is regulated by state governments, not federal agencies. In embracing raw milk, Kennedy is following an established trend as much as leading it. The roots of the movement stretch back decades.

The small independent health food stores my parents frequented in New Mexico in the 1980s, for example, sold raw milk. We never partook. But to hear Mark McAfee tell it, the pandemic supercharged demand. McAfee heads one of the largest producers of raw milk in the country, raw farm in California. McAfee, who has said Kennedy is a customer, has applied to serve in an advisory role at HHS at the urging of Kennedy's transition team, he says.

During the pandemic, McAfee told me, people felt abandoned by medical professionals and began researching ways to care for their own immune systems. Many turned to raw milk, which he calls the first food of life. Maybe they thought it could protect them from the coronavirus, he says, an unproven idea that may stem from the observation that human breast milk provides nursing infants with some protection against infection. Anecdotes of seemingly miraculous cures from raw milk also help fuel the phenomenon. Inflammatory diseases that go into remission, allergies and digestive problems that disappear. McAfee eagerly shared such stories.

Nonetheless, his customers defy easy categorization. When he began selling raw milk 25 years ago, hippie, nuts and berry moms and natural foodies, as he puts it, formed McAfee's core clientele. But as his sales have grown, about 30-fold since then, he estimates, his customers have grown, about 30-fold since then, he estimates, his customers have diversified. Today's raw milk movement is made up of people and ideas from across the political spectrum, back to the land types seeking unadulterated whole foods, health fanatics seeking the latest

superfood, don't tell me what to eat, libertarians who distrust authority and who, in McAfee's description, intend to do the opposite of whatever the FDA says. A variety of labels have been applied to the movement – food sovereignty, slow food, real food, food freedom. Furthermore, conspiratorially minded, raw milk represents food free of government meddling. For those merely chasing the latest fad, raw milk may be a status symbol. A single gallon can cost nearly $20. There are numerous reasons to be skeptical about these claims and the fervor behind them, not least of which is that unpasteurized dairy products are 840 times as likely as their

pasteurized counterparts to lead to infection times as likely as their pasteurized counterparts to lead to infection and illness, according to the Centers for Disease Control and Prevention. For all the care McAfee says he takes, health authorities have linked his dairy with several disease outbreaks over the years, and the government has pursued legal action against him in the past. McAfee says the FDA is simply bent on suppressing raw milk. And yet there is also a wealth of epidemiological research, most of it from Europe, that suggests that drinking raw milk early in life can protect against the development of asthma and allergies

later. Even if this science does not indicate that raw milk can cure disease, but only prevents certain conditions from developing, the basic notion animating the raw milk movement that something good and healthful is lost during processing may have some validity to it. No researcher I spoke with, including the scientists most familiar with the putative benefits of raw milk, recommended that people drink it. The risks are too great to be offset by the possible benefits.

Between 1998 and 2018, at least 2,645 people fell ill after drinking raw milk. According to data from the Centers for Disease Control and Prevention, 228 of them were hospitalized, three died. More than 200 people have been sickened in outbreaks since then, according to the CDC's National Outbreak Reporting System, which doesn't include all cases. And as the H5N1 bird flu has infected dairy herds across the country in recent months, with the first human fatality, most likely from direct contact with infected birds,

coming in the first week of January, public health experts have become increasingly concerned that consumers could contract the virus from raw milk. Yet these cautions shouldn't obscure the importance of what these same scientists may have uncovered. Over the course of the 20th century, a rising tide of allergic diseases engulfed the developed world. Children seemed increasingly vulnerable to asthma, hay fever, eczema, food allergies, and other allergic problems.

These trends have baffled scientists. The allergens now causing so much misery, from dust mites and tree pollen to nuts and wheat, weren't exactly new to the human experience. Why were people now so sensitive to them? The discovery around the turn of the millennium that some groups of people were relatively resistant to this trend, including a subset of European children who were drinking raw milk, suggests there might be a fix to what is often

called the allergy epidemic. Scientists think that if they can identify what's special about raw milk and preserve it through treatment that makes it safe, maybe they can turn a widely consumed foodstuff into a powerful tool of preventive medicine. With Kennedy now tapped to helm HHS, scientists and public health experts face a conundrum. Should they flatly deny that raw milk has any health benefits, a long-standing strategy that risks driving curious people to less reliable sources of information? Or should they try to directly address what truths might be found among this consumer movement? be found among this consumer movement. The modern story of Rob Milk and his possible health benefits begins in the late 1990s when

Charlotte Braun Farlander, then an epidemiologist at the University of Basel in Switzerland, received a tip from a local village doctor. The children of farmers seemed to suffer from allergies much less frequently than other village children. The first study by Braun-Farlonder and her colleagues investigating this observation, published in 1999, corroborated the village doctor's impression, documenting a strong inverse relationship between farming and allergic disease. Children on farms were about one-third as allergic as measured by specific antibodies

in their blood and their propensity for sneezing attacks during hay fever season as their non-farming peers in the same rural areas. And the more intensively their families farmed, part-time versus full-time, the more protected they were. That finding sparked what has become its own small field of scientific inquiry. In the decades since, Ron Farlander and others have published dozens of studies comprising thousands of children on what is now known as the farm effect. The effect has been observed on farms in Switzerland, Austria, Germany, France, Britain, Finland,

and most recently among some farming communities in the United States. Researchers have settled on two distinct kinds of exposure that they think explain how farming may lower the risk of allergy and asthma. First is the microbially rich environment of farms with animals, particularly cows. The greater the exposure to animals, cow sheds and fermented feed, the stronger the protection against a variety of allergies. The second factor, which seems to work independently of the first, is the consumption of raw milk. Children who don't live on farms but who might acquire raw milk from one nearby also

have a lower risk of these diseases. And the earlier the initial exposures, whether to microbes or raw milk, the more protection children seem to get. The relevant farms are generally small, family-run affairs, not the large, daring operations that tend to dominate in the United States. The distinct lifestyle is important, scientists think, for how it determines the timing and variety of exposures throughout childhood. Expectant mothers might work with animals during pregnancy, they might also consume raw milk while pregnant. And their infants might begin drinking it after they are weaned.

Children might play in the cow shed, ensuring exposure to an abundance and variety of microbes well into their youth. It's many effects that overlay, says Markus Ega, a scientist at the German Center for Lung Research at Ludwig Maximilian University of Munich who studied the farm effect. Together they give a strong effect. The constant stimulation of immune systems in such conditions seems to set them on a specific trajectory of development. At birth, their umbilical cord blood already contains more regulatory T-cells thought to

prevent allergy than that of newborns in non-farming environments, and their immune systems continue to be measurably different for years to come. Disentangling precisely what features of an alpine farm are most important – mud, manure, fermented feed, fungi, raw milk – has been maddeningly difficult, however. Scientists I spoke with who were familiar enough with this research to comment on it knowledgeably were usually convinced that the farm effect is real without being exactly sure how it works. Christine Tsurugi, a pediatric allergist and immunologist at the University of Wisconsin-Madison who has begun to study the farm farm effect in the states Amish, Mennonite and other farming communities, doesn't think that European studies have satisfactorily determined the extent to which raw milk alone contributes to the protective effect of farming.

I'm not ignoring their findings, she told me, but I think we want to understand mechanism and biology. The best way to prove that raw milk really does improve human health would be to give it to children from non-farming environments and then measure their health outcomes over time compared with the health of children drinking pasteurized milk.

The trouble, of course, is that getting ethical approval for such an experiment is difficult because of the risks involved. So the next best approach is to study animals. About a decade ago, Betty Von Esk, an immunologist at Utrecht University in the Netherlands, began a series of mouse studies, partly funded by Danone Research and Innovation,

to ascertain whether raw milk might prevent allergy and asthma. Using untreated milk from an organic dairy farm in Germany, where the sale of raw milk is legal and regulated, she and her colleagues found that raw milk does seem to alter how the mouse immune system responds to allergens. In a food allergy experiment, giving mice the human equivalent of two glasses of raw milk a day for eight days greatly dampened the allergic reaction to egg protein. In another experiment meant to simulate asthma, raw milk also blunted the reaction to dust mites, a common respiratory allergen.

Heat-treated milk did not have this effect. Van Esk is still investigating why. She talks about the matrix of milk, the fact that, as an evolutionary artifact, milk does many things at once. Certain bioactive molecules in cow's milk, it contains whey proteins such as lactoferrin, they may subtly stimulate the immune system as well as signaling molecules called cytokines and antibodies, most likely work to direct the calf's immune system toward healthy development. And because many of these molecules are sensitive to and are formed by high temperatures, heating milk may nullify their benefits. In a study with just nine participants, Van Ask also found that children already allergic to milk were better able to tolerate raw milk

than milk treated with high heat, suggesting that such processing may somehow make the milk itself more allergenic. Importantly, the bovine versions of the cytokines thought to help prevent allergy in human milk are close enough to their human counterparts for the human immune system to recognize and respond to them, says Joost van Nierven, an immunologist who studies milk at Wageningen University in the Netherlands. Some antibodies in cow's milk may also bind to allergens and prevent them from spurring a reaction in people, he says. Other antibodies may lessen the severity of infections like RSV, a virus linked to the development of asthma. An intriguing epidemiological finding is that children on farms who drink raw milk have

a 30% reduction in symptomatic colds in the first year of life compared with those who don't. Another possible explanation for the beneficial effects associated with raw milk may be how it affects the community of microbes inhabiting farming children's bodies. Microbiologists believe that these microbes, which mostly live in the large intestine, greatly influence how the immune system works and whether it's prone to allergic or autoimmune diseases. And epidemiologists studying the farm effect have in fact found that children on farms

tend to develop, earlier in life than their non-farming peers, a microbiome that produces more of a metabolite called butyrate. The more butyrate produced, the lower the chance of developing asthma. How drinking raw milk might contribute to this shift is unclear. Carolyn Ruddely, a pediatric allergist at the University of Bern Hospital in Switzerland, posits that the combination of breast milk with the early life introduction of raw cow's milk may help seed children's microbial communities with key species they don't come by otherwise. These bugs could then enhance their ecosystem's ability to produce butyrate and other metabolites when the children eat fiber and certain starches.

Raw milk may prevent the emergence of asthma and allergic disease by essentially fine-tuning the microbiome, a kind of pharmaceutical factory within us, to children's benefit. All of the scientists working in this field agree that more research is needed. Erika von Multius, director of the Institute of Asthma and Allergy Prevention at Helmholtz, Munich and a senior author on many of the farm effect studies, sketched out a best-case scenario in the current American political moment. Perhaps Kennedy's ascension, which has already put the spotlight on raw milk, would provide an incentive to study this more carefully, she said. And maybe we don't even need to figure out the exact mechanism by which raw milk confers

its benefits. Some experts told me that new processing technologies could lessen the need to heat milk, thereby preserving its mysterious protective quality, using ultraviolet radiation to kill pathogens in milk, for example, or membrane filters to remove them. Bedi von Esch points out that fermenting raw milk into kefir raises acidity, which could kill off pathogens while preserving milk's anti-allergic virtues. Simply using less heat during treatment might be another approach. Joost van Nierven notes that higher temperatures alter what may be the key milk proteins more than lower temperatures do. Indeed, Marcus Iga,

Erika von Muthius and their colleagues are testing minimally heated milk in an ongoing study with children. When it comes to the broader raw milk movement, scientists worry that in pursuit of uncertain benefit, aficionados will expose themselves to significant risk. Von Muthius, a pediatrician, recalls seeing earlier in her career children in the intensive care unit, sickened by foodborne illnesses. I'm sorry, but it's not a little side effect you have, a bellyache or something. She told me, the milk can be contaminated by one pathogen, cause severe disease and even kill.

Most of the cow's milk that has been studied comes from small alpine farms. Cows in other environments eating different feed do not necessarily produce milk with the same protective qualities. Moreover, anyone inspired to begin drinking raw milk might be overlooking the fact that the current evidence indicates the preventive medicinal power of raw milk probably comes from starting to drink it early in life. The Farm Effect research has not investigated whether there is any benefit for those who start drinking it as adults. The movement also tends to disregard the particular immunological conditioning that occurs on

farms, von Mutius says. The abundance of microbial stimuli in those settings may enhance children's ability to fight off infectious organisms, including those found in raw milk. They have a different immune system, she says. These children are much more protected. If it is crucial to acknowledge these sorts of nuances and uncertainties, it is also important to recognize the vein of truth running through the raw milk movement.

The health value of raw milk may be greater than the basic nourishment it provides, and may contain ingredients that benefit human health in extra-nutritional ways that haven't received much consideration in the past, mostly because no one knew they mattered. Now, as Kennedy and others who have long railed against the government agencies tasked with caring for Americans' health appear set to wield influence over them, scientists face a delicate balancing act. How do they discuss frankly not just the risks, but also the possible benefits of raw milk without encouraging more of the unfounded claims and misinformation that already abound? Christine Suruji of the University of Wisconsin told me that while she no longer thinks that

scientists should dominate discussions about raw milk, you need to have multiple stakeholders at the table. Like the families interested in drinking it, the producers, the regulators, facts should still guide the conversation. Good decisions, she says, come from good information.