Raw milk has regained attention on social media, with claims that it contains more nutrients, improves digestion, supplies beneficial bacteria, or may protect against allergies and asthma. Research does contain some intriguing observations, particularly around childhood asthma and farm-milk consumption, but those findings need to be separated from evidence that actually demonstrates a health benefit from intentionally drinking unpasteurized milk. Overall, current evidence has not established a health advantage of raw milk that clearly outweighs its substantially higher risk of foodborne infection.
What Is Raw Milk?
Raw milk is milk that has not undergone pasteurization, the controlled heat treatment used to reduce disease-causing microorganisms. Pasteurization does not sterilize milk or fundamentally transform it into a different food. Its main purpose is to greatly reduce pathogens while retaining the nutritional characteristics that make milk a source of protein, calcium, phosphorus and other nutrients.
Milk can become contaminated even when a farm appears clean and the animals appear healthy. Microorganisms can originate from the animal itself, fecal contamination, the environment, milking equipment or handling after collection. Testing and sanitary farming practices can reduce risk, but they cannot guarantee that every batch of unpasteurized milk is free from pathogens.
Does Pasteurization Remove Important Nutrients?
One of the most common arguments for raw milk is that heating supposedly destroys much of its nutritional value. The research does not support such a large difference. Pasteurization can alter the concentration or activity of some heat-sensitive compounds, but the major nutrients in milk remain largely available.
A systematic review examining vitamins found measurable changes in several vitamins after pasteurization, including some reductions in heat-sensitive B vitamins, vitamin C and folate. However, the researchers concluded that the overall effect on the nutritional value of milk was minimal, partly because milk is not an important dietary source of several of the vitamins most affected by heating.
Protein, calcium, lactose and the major fat components do not disappear during normal pasteurization. Consequently, there is no strong evidence that choosing raw milk provides a meaningful nutritional advantage over comparable pasteurized milk.
Are the Enzymes and Bacteria in Raw Milk Beneficial?
Raw milk contains microorganisms and biologically active compounds that can be reduced or altered by heat. That observation is sometimes expanded into the claim that raw milk functions as a natural probiotic food, but the two ideas are not equivalent. A probiotic is generally a specifically identified microorganism supplied in an amount shown to provide a health benefit.
The microorganisms present in untreated milk are variable and uncontrolled. Some may be harmless, while others can include Campylobacter, Salmonella, Shiga toxin-producing Escherichia coli or Listeria monocytogenes. The presence of live microorganisms by itself therefore does not establish a probiotic benefit.
Fermented dairy products are a different case. Yogurt and certain cultured dairy foods use selected microorganisms under controlled manufacturing conditions, and some of those cultures have evidence supporting particular digestive effects. Those findings should not be transferred automatically to microorganisms found unpredictably in raw milk.
The important distinction is not simply whether bacteria or enzymes survive. The relevant question is whether a specific component has been demonstrated in human studies to improve a meaningful health outcome at the amount normally consumed, without introducing a disproportionate safety risk.
Is Raw Milk Better for Lactose Intolerance?
Another recurring claim is that people with lactose intolerance can digest raw milk more easily. A randomized crossover pilot trial directly tested this idea in adults with confirmed lactose malabsorption. Participants consumed raw milk and pasteurized milk during separate study periods while researchers measured hydrogen production and digestive symptoms.
The study did not find raw milk to reduce lactose malabsorption or symptoms compared with pasteurized milk. At one measurement point, hydrogen production was actually higher after raw milk, while later measurements showed no meaningful difference between the two dairy milks.
Raw milk therefore should not be considered an established treatment for lactose intolerance. The lactose remains present regardless of whether milk has been pasteurized. For people who have difficulty digesting lactose, lactose-free products and certain fermented dairy foods provide alternatives supported by more relevant evidence.
What Do the Asthma and Allergy Studies Show?
The allergy and asthma research is the most scientifically interesting part of the raw-milk discussion. Several observational studies involving children in European farming communities have found associations between consumption of raw or minimally processed farm milk and lower rates of asthma, wheezing, allergic rhinitis or allergic sensitization.
A 2020 review and meta-analysis reported that early-life raw farm-milk consumption was associated with lower odds of several allergic outcomes. For asthma, the pooled association corresponded to an odds ratio of approximately 0.58. Other studies have investigated whether whey proteins, fatty components or other heat-sensitive milk constituents might help explain the observation.
However, an association does not demonstrate that giving children raw milk prevents asthma. Many of the relevant studies are observational, meaning families were not randomly assigned to drink raw or pasteurized milk. Farm environment, microbial exposure, animal contact, lifestyle, diet, socioeconomic factors and differences in milk production can complicate attempts to isolate a single causal factor.
Importantly, even researchers investigating the possible protective association have discouraged intentionally feeding children raw milk because of the infection risk. Research has instead explored whether the potentially relevant components could eventually be preserved in a microbiologically safer, minimally processed milk.
The asthma findings therefore represent a research hypothesis with epidemiological support, not a recommendation to use raw milk as an asthma-prevention strategy.
How Much Greater Is the Infection Risk?
The difference in foodborne-disease risk is much better established than most proposed health benefits. A U.S. analysis of dairy-associated outbreaks from 2009 through 2014 examined illnesses involving pathogens including Campylobacter, Salmonella, Listeria and Shiga toxin-producing E. coli.
The researchers estimated that unpasteurized milk and cheese accounted for 96% of illnesses attributed to contaminated dairy products in the dataset despite being consumed by relatively small percentages of the population. Their model estimated approximately 840 times as many outbreak-associated illnesses and 45 times as many hospitalizations from unpasteurized dairy products as from pasteurized products on a consumption-adjusted basis.
Those figures come from a particular historical dataset and statistical model, so they should not be interpreted as a guarantee that an individual glass of raw milk is 840 times more likely to make someone ill. They do, however, illustrate the substantial difference in population-level risk observed between pasteurized and unpasteurized dairy products.
Most exposed people will not necessarily become seriously ill, but the consequences can be severe when contamination does occur. Young children, pregnant people, older adults and people with weakened immune systems face particular concern because infections such as listeriosis or Shiga toxin-producing E. coli can result in severe complications.
Why H5N1 Has Added Another Raw Milk Concern
The detection of highly pathogenic avian influenza A(H5N1) in U.S. dairy cattle beginning in 2024 added another reason for public-health agencies to discourage raw milk consumption. Investigations detected infectious virus in some raw milk collected from affected dairy herds, demonstrating that viable H5N1 can occur in untreated milk under outbreak conditions.
Research using commercial pasteurization conditions has found pasteurization effective at inactivating H5N1 in milk. The U.S. Food and Drug Administration has also tested hundreds of pasteurized retail dairy samples without detecting viable H5N1 and continues to regard the pasteurized commercial milk supply as safe.
Whether drinking contaminated raw milk can transmit H5N1 to humans has not been established in the same way as traditional foodborne bacterial infections. That uncertainty is not evidence of safety, however, and health authorities continue to recommend avoiding unpasteurized milk while surveillance and research continue.
Raw Milk Claims Compared With the Evidence
| Claim | What Research Shows | Strength of Conclusion |
|---|---|---|
| Raw milk is substantially more nutritious | Pasteurization can alter some heat-sensitive compounds, but major nutrients remain and the overall nutritional difference is generally small. | No established meaningful advantage |
| Raw milk helps lactose intolerance | A randomized crossover study did not find improved lactose digestion or symptoms compared with pasteurized milk. | Not supported |
| Raw milk is a natural probiotic | Its microorganisms are uncontrolled and are not equivalent to characterized probiotic cultures used in fermented foods. | Not established |
| Raw milk prevents allergies or asthma | Observational studies have found an association between farm-milk consumption and lower rates of asthma and allergy, but causation and the responsible factors remain uncertain. | Interesting but unproven as an intervention |
| Clean farms eliminate the infection problem | Pathogenic contamination can occur even when animals appear healthy and hygienic practices are used. | Not supported |
| Pasteurization reduces pathogen risk | Pasteurization is effective against major milk-borne pathogens and has also been demonstrated to inactivate H5N1 under commercial processing conditions. | Strongly supported |
How Should the Evidence Be Interpreted?
Raw milk is not nutritionally empty, but that is because milk itself is nutritious rather than because it is unpasteurized. Research has not demonstrated that raw milk provides a clinically meaningful nutritional, digestive or probiotic advantage over pasteurized milk. The claim that it improves lactose intolerance has been directly tested and was not supported.
The possible relationship between early farm-milk exposure and lower rates of asthma or allergies deserves continued research. It may eventually help scientists identify milk components or processing techniques that preserve useful biological characteristics while controlling pathogens. At present, however, observational associations do not establish that deliberately drinking raw milk produces those benefits.
By contrast, the increased risk of microbial contamination and foodborne disease is well documented. The evidence therefore supports distinguishing between an interesting scientific question about components of minimally processed milk and the separate decision to consume milk without an established pathogen-reduction step.
For further technical information, the U.S. Food and Drug Administration provides guidance on raw-milk safety, while the allergy findings can be explored through the published farm-milk and asthma review. The comparative outbreak-risk analysis is also available through PubMed.
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raw milk benefits, raw milk risks, pasteurized milk, raw milk studies, raw milk asthma, raw milk allergies, lactose intolerance, foodborne illness, milk nutrition, pasteurization
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