Research shows raw milk dramatically increases risk for illness


BALTIMORE — Researchers discourage the consumption of raw milk, especially by children, pregnant women and the elderly. An analysis conducted by researchers at the Johns Hopkins Center for a Livable Future (CLF) found that the risks of drinking raw (unpasteurized) cow’s milk are significant.

Consumers are nearly 100 times more likely to get foodborne illness from drinking raw milk than they are from drinking pasteurized milk. In fact, the researchers determined that raw milk was associated with over half of all milk-related foodborne illness, even though only an estimated 3.5 percent of the U.S. population consumes raw milk.

Based on their findings, the researchers discourage the consumption of raw milk, which some claim is healthier and tastes better than pasteurized milk.

They note that the risks are better understood than the benefits, and that further research is needed to determine whether the health benefit claims are legitimate.

The CLF analysis was prepared at the request of the Maryland House of Delegates’ Health and Operations Committee as lawmakers considered relaxing regulations that currently prohibit the sale of unpasteurized milk in Maryland.

In the 2014 legislative session, H.B. 3 aimed to legalize the on-farm sale of unpasteurized milk in Maryland. The bill was tabled as legislators considered the issue. The research team presented its report to the House of Delegates last month.

Raw milk has become more popular in recent years, even though in many states it is only available for direct purchase at farms.

Advocates believe that raw milk, which contains more natural antibodies, proteins and bacteria than pasteurized milk, is healthier, cleaner, tastes better and reduces lactose intolerance and allergies in certain people.

Pasteurizing milk

Pasteurization, named after Louis Pasteur, involves heating milk to destroy microbes that may have entered the milk supply from fecal contamination, dairy operations, cow udders or other sources.

The treated milk is then hermetically sealed to prevent recontamination.

“Ultimately, the scientific literature showed that the risk of foodborne illness from raw milk is over 100 times greater than the risk of foodborne illness from pasteurized milk,” said report lead author Benjamin Davis, a CLF-Lerner Fellow and doctoral candidate in the Johns Hopkins Bloomberg School of Public Health’s Department of Environmental Health Sciences.

“Although potential benefits related to the consumption of raw milk would benefit from further investigation, we believe that from a public health perspective it is a far safer choice to discourage the consumption of raw milk,” he continued.

How it worked

For their study, a team of investigators led by Keeve Nachman, PhD, director of the Public Health and Food Production Program at CLF and an assistant professor with the Bloomberg School, screened approximately 1,000 articles and reviewed 81 published journal articles relevant to the health risks and benefits of consuming raw cow’s milk.

Microbial contaminants commonly found in milk include infectious Salmonella, Campylobacter and Listeria species along with the Escherichia coli type O157:H7.

These bacteria can cause foodborne illness in humans, including diarrhea, vomiting, cramping, fevers, and sometimes more serious consequences such as kidney failure or death.

“The risks of consuming raw milk instead of pasteurized milk are well-established in the scientific literature and in some cases can have severe or even fatal consequences,” noted co-author Cissy Li, a CLF research assistant and doctoral candidate with the Bloomberg School’s Department of Environmental Health Sciences.

“Based on our findings, we discourage the consumption of raw milk, especially among vulnerable populations such as the elderly, people with impaired immune systems, pregnant women, and children,” Li continued.

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  1. No direct research has been done on this topic. This is a literature review not an actual hard core study done on the cattle. With people like the Coke Company and other big Pharma there’s no way they’re gonna let individual farmers sell their own milk directly off their farm.
    This is typical of the bias that exist in the healthcare and other scientific communities on the subject

  2. ALL of the pathogens listed are from milk that has been contaminated with manure. While I am not at all afraid to drink my own raw milk, I only know of one other dairy I would not be afraid of drinking from. With such low milk prices being paid to farmers for milk, they can not properly clean the cows before milking because of time constraints and being forced to increase their herd numbers to make a living. While this article did not name dairy processors, most of them have contacted farmers to encourage us to support bans of raw milk-something I REFUSE to do. We live in a free country-people have the right to eat what they choose, and NO ONE has a right to tell them what they may or may not consume….This entire raw milk deal will “back-fire” when people find out that the pasturized milk that is touted as “safe” is just as contaminated with cow crap as any raw milk that is deemed harmful. Those processors attacking raw milk are also hurting themselves but are too “self-righteous” to see it.

    • I wholeheartedly agree with the assertion that people (farmers and consumers) should have the right to engage in free enterprise (accepting both the risks and rewards) when it comes to ALL forms of direct farm to consumer products (milk, meat, veggies, eggs, etc) It is an outrage how the feds have stepped in to crush small farmers who didn’t comply with ridiculous and expensive regulations (see the film Farmaggeddon).

      The reason I am replying to your comment Fed Up is I take issue with the reference of low prices and lack of time as the reasons farmers can’t comply with cleanliness standards. That’s pure BS and a total cop-out. If a farmer cannot take the time or effort to employ proper management practices in order to ensure that udders are clean, facilities are clean, and cows are healthy, then perhaps they should not be in the business of producing a food product. Would you not agree?

  3. You obviously know very little of modern farming. Farmers can not set their price-they get what the market pays them. The “Walmart effect” has hit modern agriculture, and processors put enormous pressure to get basic food at the cheapest price possible. I completelly disagree with your statement that farmers should not be in business just because they can NOT keep their cows’ udders clean enough to make sure that no manure enters the milk supply. In order to make sure their is no manure that gets into the milk supply,, cows must be thoroughly and completely washed, dried, stripped, dipped, then wiped off . This takes far too long for the milkers to do when you have hundreds or more cows. The usual protocol is just dipping with a solution then wiping off. It gets much of the manure/dirt, but not all. Remember, all meat has handling recommendations and cooking recommendations also…when you have plants that process thousands of head per day-more if poultry-speed is vital, thus a different story than just butchering a few hens a day or a beef/hog a few times per year. It is the price of having the cheapest, most abundant food ever produced in history. A few sicknesses is nothing compared to the deaths from famines in the past. Never-the -less, it should entirely be personal choice.

    • I milked cows for 20 yrs, so naturally I take issue with your condescending tone and assumption that I “obviously know very little of modern farming”. Udders were religiously washed, wiped, pre-stripped, and dipped each cow. 100 cows, housed in 50 ties, the other half in loose housing. Cell counts were always around 150K.
      Look, I get where you’re going with your long and drawn out reply, but I stand by my original statement. Cleanliness is a MANAGEMENT issue. If cows are coming into the parlor on a regular basis (not just once and a while) with udders so filthy that it “takes far too long for the milkers to do when you have hundreds or more cows”, then perhaps the management of the the facilities should come into question. Or, maybe the milkers are just too lazy to follow proper protocol.

      You make it sound as if there is no time for proper management on modern dairies and I can assure you that there are many large scale dairymen who would refute that idea.

      • I will agree to disagree, and stand firmly behind my statement. I guess I have been milking longer than you, and have been thru changes in the industry. My supplier no longer carries udderwash and has to special order it-jn his words “NO ONE washes their cows anymore”. I have yet to see a large dairy do anything but dip, and I have seen both confined and pastured cows dirty. Cows are filthy animals and have absolutely no sense of cleanliness, and when they poop their crap splatters back onto the udders. I am glad you are concerned about your cleanliness, but getting back to the article, raw milk is only dangerous if it is contaminated by pathogenic bacteria, which are primarily the result of contamination from manure. If people choose to purchase raw milk, their chosen supplier should be one who takes great pain to make sure their milk is from the cleanest possible cows under the most hygenic milking protocols.;and people must be made responsible for their own actions-both consumers and producers, and know what is expected from each other in the form of private agreements-NOT government mandates.

  4. This is not the story for all raw milk dairies.

    Organic Pastures is once again leading the way in raw milk production safety. In addition to our RAMP Food Safety Plan and our Raw Milk Institute Listing, our team has been developing an innovative testing program for the past year. We are proud to announce our partnership with Food Safety Net Services for PCR/BAX E.coli O157:H7 testing on our milk filters, in addition to pathogen, coliform and SPC tests on final milk products. Testing milk filters is an innovative technology that has been shown to be up to ten times more sensitive to detection of pathogens than other testing methods.

    Triple Tested: In addition to State of California and local county Health Department monthly testing, we test our raw milk (as a final product) at a state approved 3rd party laboratory, on a daily basis. This extra testing is not required by the State, but is an extra step we choose to take as a commitment to our customers and food safety.

    Test and Hold: Before we release our raw milk for sale, the milk filters from each shift of milking are tested to be free of E.coli O157:H7 via ultra sensitive, PCR/BAX testing technologies. All results are received back to us within 16 hours of milking the cows. This is a revolution in technology; up until this year, tests could take up to 72 hours or longer for results.

    CEO Mark McAfee stated, “After extensive research and a year of filter testing, we have now arrived at a time where speed of technology and our experience has created a truly low risk and very safe raw milk. These pioneering efforts are in service to our wonderful consumers and the emerging raw milk markets.”

    Organic Pastures Dairy was founded in 2000 to provide thousands of hungry Californians with delicious, safe raw milk. We are ranked fourth nationally in the natural dairy brand sector and we are the fastest growing natural dairy brand in the USA (SPINS data monitor). Please visit our website to learn more.


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