Raw milk carries a significantly higher risk of foodborne illness than pasteurized milk. Consumers of unpasteurized milk or cheese face more than 800 times the risk of getting sick compared to those who drink pasteurized dairy, according to CDC data from 2009 to 2014. Despite making up a small fraction of total dairy consumption in the United States, unpasteurized products account for 95% of dairy-related illnesses.
What’s Actually in Raw Milk
Raw milk can harbor several dangerous bacteria. Testing has found Salmonella in about 4.6% of samples, Shiga toxin-producing E. coli (STEC) in roughly 2.5%, and Listeria in about 2.5%. Campylobacter, one of the most common causes of bacterial diarrhea, is also frequently detected. These pathogens typically enter the milk at the dairy farm itself, through contact with animal feces, udder infections, or contaminated equipment. Even farms with excellent hygiene practices cannot guarantee a pathogen-free product because contamination can happen at any point before the milk reaches your glass.
These aren’t just stomach bugs. In a review of outbreaks linked to unpasteurized dairy in Canada and the United States, 23% of the 530 reported illnesses required hospitalization. Six cases, about 1.1%, resulted in hemolytic uremic syndrome, a serious kidney condition most often triggered by certain strains of E. coli. Young children, pregnant women, older adults, and anyone with a weakened immune system face the highest risk of severe outcomes.
The Bird Flu Factor
H5N1 avian influenza has added a new layer of concern. Infected dairy cows can shed extremely high concentrations of the virus into their milk. Refrigeration slows the virus’s breakdown but doesn’t eliminate it. Milk’s high protein content actually stabilizes the virus, allowing it to survive longer than it would in other environments. Researchers estimate that infectious virus could theoretically persist in refrigerated raw milk for 45 days or more. Standard pasteurization effectively kills the virus, which is one reason public health agencies have emphasized the importance of heat treatment during the ongoing outbreak in U.S. dairy herds.
Does Pasteurization Destroy Nutrients?
This is one of the most common arguments for drinking raw milk, and it contains a grain of truth. A systematic review and meta-analysis found that pasteurization does reduce levels of vitamins B1, B2, C, and folate by measurable amounts. Vitamins B12 and E also decreased. Vitamin A, interestingly, slightly increased after heat treatment, and vitamin B6 showed no significant change.
In practical terms, though, these losses are modest and rarely nutritionally meaningful. Milk is not a primary dietary source of vitamin C or folate for most people. The B vitamins that decline are easily obtained from other foods. No major nutrition authority considers the nutrient differences between raw and pasteurized milk significant enough to justify the infection risk.
The Allergy and Asthma Question
Some of the most intriguing evidence in favor of raw milk comes from studies on childhood allergies. The GABRIELA study, a large European investigation of farm children, found that kids who drank raw milk had a 41% lower risk of asthma and a 26% lower risk of allergic sensitization compared to those who didn’t. Boiled farm milk did not show the same protective effect, suggesting that heat-sensitive components in the milk were responsible.
The researchers traced the benefit to whey proteins, specifically types that break down during pasteurization. Children exposed to higher levels of these proteins had significantly lower asthma risk. This is a real and reproducible finding, but it comes with important context: the study observed farm children who grew up with broad microbial exposures from birth. Whether drinking raw milk as an adult in a suburban kitchen produces the same immune effects is unknown. And the researchers themselves noted that the infection risks of raw milk make it unsuitable as a public health recommendation, even given the allergy findings.
Raw Milk Won’t Help Lactose Intolerance
A persistent claim holds that raw milk is easier to digest for people who are lactose intolerant, supposedly because it contains natural enzymes that help break down lactose. A randomized controlled trial tested this directly. Sixteen adults with confirmed lactose malabsorption drank raw milk, pasteurized milk, and soy milk in random order over separate eight-day periods. The results were clear: raw milk produced no reduction in lactose malabsorption and no improvement in digestive symptoms compared to pasteurized milk. Symptom severity scores were essentially identical between raw and pasteurized at the highest dose.
What About Probiotics?
Raw milk does contain a more diverse bacterial community than pasteurized milk. Molecular analysis has identified genera like Bacteroides, Faecalibacterium, and Prevotella in unpasteurized samples, some of which had never been documented in milk before. Proponents point to this microbial diversity as a benefit for gut health.
The problem is that bacterial diversity in milk doesn’t automatically translate to probiotic benefit in your gut. Many of these organisms don’t survive stomach acid. The bacteria that do survive are present in unpredictable quantities that vary from farm to farm and day to day. And the same diversity that includes potentially helpful species also includes the pathogens described above. A commercial probiotic supplement delivers specific, well-studied strains in controlled doses without the infection risk.
Where Raw Milk Is Legal
Federal law prohibits selling unpasteurized milk across state lines for human consumption. Within states, the rules vary widely. Some states allow raw milk sales in retail stores. Others permit sales only at the farm where the milk was produced. A growing number of states allow herd-share or cow-share arrangements, where you buy partial ownership of a cow and receive a portion of its milk, effectively sidestepping retail sales bans.
Some states still prohibit any sale of raw milk to consumers. The legal landscape shifts frequently, so checking your state’s current regulations is worthwhile if you’re considering purchasing it. Legal status, of course, is not the same as a safety endorsement. States that allow raw milk sales generally require warning labels, not because the product is approved as safe, but because legislators have weighed consumer choice against public health risk and landed on disclosure rather than prohibition.
The Bottom Line on Risk vs. Benefit
The core question is whether any benefit of raw milk justifies the documented risks. The nutrient differences are small. The lactose intolerance claim doesn’t hold up in clinical testing. The allergy findings are real but specific to early childhood farm exposures and not easily replicated by simply switching to raw milk. Meanwhile, the risks are concrete: dangerous bacteria in a measurable percentage of samples, a hospitalization rate of nearly one in four among those sickened in outbreaks, and a new viral threat that persists in refrigerated raw milk for weeks. For most people, pasteurized milk delivers virtually the same nutritional profile without the gamble.