Raw milk is often praised for its potential health benefits, but how do those claims stack up against the risks? This episode breaks down the science behind unpasteurized dairy, exploring its possible links to allergy prevention, the dangers of foodborne illness, and the regulations designed to protect consumers.
Raw milk is often praised for its potential health benefits, but how do those claims stack up against the risks? This episode breaks down the science behind unpasteurized dairy, exploring its possible links to allergy prevention, the dangers of foodborne illness, and the regulations designed to protect consumers.
Resources:
The Dangers of Raw Milk: Unpasteurized Milk Can Pose a Serious Health Risk | FDA
Raw and Heat-Treated Milk: From Public Health Risks to Nutritional Quality
Investigation of Avian Influenza A (H5N1) Virus in Dairy Cattle | FDA
Welcome to the Nutrition Diva Podcast, where we take a closer look at nutrition news, research, and trends so that you can feel more confident about what you eat. I'm your host, Monica Reinagel, and today, we’re talking about a subject that has been (back) in the news lately: the risks and potential benefits of drinking raw (unpasteurized) milk.
Virtually all of the milk for sale in grocery stores has been pasteurized, meaning that it has been briefly heated in order to kill microorganisms that might make you sick. The widespread adoption of this process in the early 20th century represented a huge advance for public health and safety.
However, a lot of people (including our recently confirmed Secretary of Health and Human Services) believe that raw, unpasteurized milk might actually be better for you. A 2017 survey found that about 4% of U.S. adults said they had consumed raw milk in the past year, with 1% drinking it once a week or more. That may not sound like a lot, but it’s roughly double the estimated percentage from a decade earlier.
Depending on where you live, you might have a hard time buying raw milk. Approximately 30 states allow some form of raw milk sales, while around 20 states prohibit it entirely. Federal regulations, meanwhile, prohibit the sale of raw milk for direct human consumption across state borders, citing concerns about public safety. Secretary Kennedy has characterized these regulations as 'aggressive suppression' and expressed support for deregulating raw milk at the federal level.
Unfortunately, as is so often the case, the more heated a debate gets, the more misinformation it seems to generate. A lot of what I’ve seen about raw milk tends to understate the risks and overstate the benefits. And we are also seeing instances of public health information being removed from governmental websites. So, in today’s episode, I want to take a closer look at the pros and cons of raw milk, so that you can make a rational decision.
Let’s start with the risks. Raw milk can contain microorganisms that can make you sick, including E. coli, salmonella, and listeria. If one of these bugs takes hold in your gut, you might spend the weekend in the bathroom—or you could end up in the hospital. In rare cases, foodborne illnesses can be fatal. As with any infectious disease, young children, the elderly, pregnant women, and those with impaired immune systems are at the greatest risk.
And now, there is also concern about avian influenza (or bird flu) in raw milk. Although there have not been confirmed human infections linked to raw milk consumption, animal studies suggest that ingesting contaminated milk could plausibly lead to infection. Recent testing by the FDA found fragments of the H5N1 bird flu virus in over half of raw milk samples from several states. In a smaller number of cases, intact virus (which could actually be infectious) was detected.
Now, raw milk proponents will point out that just a few generations ago, everyone in the country drank raw milk. And that’s true. But it’s also true that raw dairy was the most common source of foodborne illness back then, and a major source of infant mortality.
Of course, keeping cows healthy and maintaining clean farms and milking operations can reduce the risk of certain pathogens—but not to zero. And, obviously, bird flu introduces a new risk that was not part of the landscape a century ago. There is no way to eliminate the risk of pathogenic bacteria in raw milk. And, contrary to what you may have read, there is absolutely nothing in raw milk that naturally kills dangerous pathogens or protects you from them.
Here in the U.S., between 2013 and 2018 (which is the most recent data we have), there were 75 outbreaks of illness linked to unpasteurized milk, resulting in 675 illnesses. Nearly half of those affected were children.
Raw milk proponents also like to point out that people can also get sick from pasteurized milk that’s gotten contaminated after the pasteurization process. And that’s true. But quite rare. People who drink raw milk are over 800 times more likely to get sick from it compared to pasteurized milk drinkers, and 45 times more likely to end up in the hospital.
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Seeing as pasteurized milk is an option, why would you take unnecessary risks by drinking raw milk?
Well, raw milk proponents point out that raw milk contains nutrients, enzymes, beneficial bacteria, and other compounds that are denatured or destroyed by pasteurization. That’s true. So the question is not whether raw milk is different than pasteurized milk; it clearly is. The question is whether these differences have a significant impact on your health. And that’s not as clear.
Let’s start with the beneficial bacteria. Foods containing friendly, lactobacillus bacteria are definitely good for you. But you’ll get far more beneficial bacteria from eating yogurt or drinking kefir than you would from drinking raw milk.
And what about vitamins and minerals? There is very little difference in the amount of B vitamins, folic acid, sodium, potassium, calcium, magnesium, iron, or zinc. In fact, pasteurized milk is generally much higher in vitamins A and D than raw milk, but that’s only because it is usually fortified with these nutrients.
About the only nutrient that is significantly impacted by pasteurization is vitamin C. However, as raw milk contains very little vitamin C to start out with, I can’t see that this would have any significant impact on anyone’s nutrient status.
Contrary to popular belief, raw milk is not lower in lactose than pasteurized milk and does not contain any lactose-digesting enzymes. Raw milk does contain some other enzymes but their role in making the milk more digestible isn’t clear. In general, the enzymes that are involved in digestion are not present in the food but rather are produced by your own body.
Most of the evidence for the benefits of drinking raw dairy is anecdotal. People report that when they started drinking raw milk, they got fewer colds, or their allergies went away, or their irritable bowel wasn’t as irritable or they were no longer lactose intolerant. These sorts of testimonials can be very compelling. But as scientific evidence, they have three major weaknesses.
Reporting bias. Anecdotal evidence may be a very accurate representation of someone else’s experience. But it doesn’t give you much information about how likely you are to have the same experience. That’s because you’re much more likely to notice and tell people about a positive response than if nothing special happens. This reporting bias tends to make positive outcomes seem much more likely than they actually are.
The scientific literature suffers from the same bias, by the way. An experiment that finds a relationship between A and B is much more likely to be published than an experiment that finds no relationship between A and B. But when you think about it, both are equally important pieces of information.
Uncontrolled variables. Another weakness with anecdotal information is that it doesn’t control for variables. Maybe switching to raw milk was part of a larger effort to improve your diet. In addition to adding raw milk, you also eliminated refined sugar and started eating more vegetables. If you then get fewer colds, who’s to say that it was the raw milk that made the difference rather than, say, the extra broccoli?
Or perhaps the year that you started drinking raw milk happened to be a year when the frost date was a lot later than usual, which lowered the pollen count that Spring. Or a year when low rainfall reduced the mold count. Is the improvement in your allergies from the raw milk or environmental factors?
There are also a lot of anecdotal reports of people who can’t drink pasteurized milk because they are lactose intolerant—yet they tolerate raw milk just fine. Remember, however, the raw milk—which is usually unskimmed—may be a lot higher in fat than the milk they had been drinking. And the higher that fat content, the lower the lactose content.
The broccoli, the frost date, the rain fall, and the fat content of the milk are all examples of uncontrolled variables.
The placebo effect. Finally, anecdotal evidence doesn’t control for the placebo effect—people often feel better simply because they think they will. If anything, the more anecdotal evidence you hear, the more likely you are to experience a placebo effect. That doesn’t make you gullible or stupid. It makes you human.
The scientific method was designed to counter these all-too-human tendencies. Anecdotal reports often suggest that something’s worth researching further. But the way we calculate the probability of certain results, control for variables, and evaluate the placebo response is to conduct controlled trials.
Unfortunately, we don’t have much in the way of controlled trials for raw milk versus pasteurized milk. The most compelling scientific claim for raw milk is that it might reduce the risk of allergies and asthma, particularly in children. The GABRIELA study, published in 2011, first identified this association, and subsequent research has supported the idea that early-life consumption of raw milk is associated with lower rates of asthma, hay fever, and allergic sensitization. However, these observational findings come primarily from children growing up on farms–a lifestyle that potentially introduces a whole lot of uncontrolled variables. Plus, we still need to weigh that potential benefit against the risks. In fact, the researchers in one of these studies concluded that the benefits do not appear to be substantial enough to justify the increased risk of foodborne illness that comes with drinking raw milk
Finally, many people feel that raw milk simply tastes better. I believe it! Raw milk is probably fresher. It may be higher in fat. It’s usually unhomogenized. All of these things could improve the flavor of the milk. However, it is possible to buy fresh, unskimmed, unhomogenized milk—direct from the farmer in those attractive glass bottles—and still have the security of pasteurization. You can go to localharvest.org to search for dairy farmers that sell direct to consumers in your location.
I hope that this episode has provided a little clarity around this issue and the show notes include links to a lot of the resources and studies I mentioned, if you’d like to dig a little deeper. If you have another question or issue you'd like me to dig into, you can email me at nutrition@quickanddirtytips.com You can also leave me a message at 443-961-6206
If you’d like to find out about having me speak at your next live or virtual event, you can learn more at wellnessworkshere.com
Nutrition Diva is a Quick and Dirty Tips podcast. Our team includes Brannan Goetschius, Nathan Semes, Davina Tomlin, Holly Hutchings, Morgan Christianson.and Nate Hoopes.
That's all for this episode. Thanks for listening! I'll see you next week.