Is there a danger in drinking unpasteurized milk?

December 25, 2025 •

4 min read

According to the Centers for Disease Control and Prevention (CDC), between 1998 and 2018, there were 202 outbreaks linked to raw milk consumption, resulting in 2,645 illnesses, 228 hospitalizations, and three deaths in the U.S. alone. These figures highlight the significant public health risk associated with unpasteurized dairy products.

Quick Summary

Unpasteurized milk poses a serious health risk due to harmful bacteria, which can cause severe foodborne illnesses and long-term complications. The heating process of pasteurization effectively eliminates these pathogens without compromising the milk's nutritional quality or taste, offering a safer alternative.

Key Points

High Contamination Risk: Raw milk can contain dangerous bacteria like E. coli, Salmonella, and Listeria that can cause severe, sometimes fatal, foodborne illnesses.
Pasteurization is Protective: The pasteurization process effectively kills harmful pathogens by heating milk to a safe temperature, a proven public health measure since the 19th century.
No Proven Health Advantage: Scientific evidence does not support claims that raw milk offers superior nutritional or health benefits over pasteurized milk, which is equally nutritious.
Increased Risk for Vulnerable Groups: Infants, young children, pregnant women, and the elderly are at a higher risk of developing severe illness from raw milk contamination.
False Sense of Security: Even milk from a seemingly clean farm or healthy animal can be contaminated, as pathogens can be shed unpredictably.
Serious Complications: Infections from raw milk can lead to serious, long-term health issues such as kidney failure, paralysis (Guillain-Barré syndrome), or chronic disorders.

The Risks of Raw Milk Consumption

Raw, or unpasteurized, milk is milk that has not been heated to a specific temperature for a set time to kill disease-causing bacteria. This process, known as pasteurization, is a fundamental public health measure that has been a standard in food production for over a century. The growing popularity of 'natural' or 'farm-fresh' products has led to a resurgence of interest in raw milk, but this trend comes with significant health hazards that consumers need to understand. Despite anecdotal claims of superior health benefits, the risks of drinking unpasteurized milk are well-documented by leading health organizations like the FDA and CDC.

Dangerous Pathogens in Raw Milk

Raw milk can harbor a variety of dangerous microorganisms, even from outwardly healthy animals or farms with strict hygiene practices. Contamination can happen at various stages, from the animal itself to the milking equipment or storage. Some of the most common and dangerous bacteria include:

E. coli O157:H7: This strain of bacteria produces a toxin that can lead to severe diarrhea, abdominal cramps, and vomiting. In vulnerable populations, it can cause hemolytic uremic syndrome (HUS), a life-threatening condition leading to kidney failure.
Salmonella: A frequent cause of food poisoning, Salmonella infection can cause fever, diarrhea, and stomach cramps. Severe cases can lead to serious and sometimes fatal systemic infections.
Listeria monocytogenes: This pathogen is particularly dangerous for pregnant women, newborns, and people with weakened immune systems. Listeria can cause listeriosis, leading to flu-like symptoms, and in serious cases, can cause miscarriage, stillbirth, or life-threatening infections like meningitis.
Campylobacter: A common cause of bacterial foodborne illness, Campylobacter can cause diarrhea (often bloody), fever, and stomach cramps. In rare instances, it can lead to Guillain-Barré syndrome, a condition causing paralysis.

The Pasteurization Process

Pasteurization is a simple yet highly effective process that involves heating milk to a specific temperature for a set period, then cooling it rapidly. The most common method, High Temperature Short Time (HTST) pasteurization, involves heating milk to at least 161°F for 15 seconds. This process is specifically calibrated to destroy pathogens while having a minimal effect on the milk's nutritional value, taste, and color. Testing for the presence of alkaline phosphatase after pasteurization is a reliable indicator that the process was successful in killing the harmful bacteria. Claims that pasteurization damages milk are not supported by scientific evidence.

Comparing Raw vs. Pasteurized Milk


Feature	Raw Milk	Pasteurized Milk
Safety	High risk of carrying harmful bacteria like E. coli, Salmonella, and Listeria, even from a clean-looking farm.	Very low risk of bacterial contamination due to the pasteurization process that kills pathogens.
Nutritional Value	No scientifically proven nutritional benefits over pasteurized milk. Essential nutrients like calcium and protein are largely unaffected by pasteurization.	Contains the same nutritional value as raw milk, with no significant difference in key vitamins and minerals.
Flavor	Some claim a richer, more 'natural' flavor, though this is subjective and not a guarantee of safety.	A consistent, standardized flavor profile that is widely accepted by consumers.
Health Claims	Purported benefits like enhanced immunity or allergy prevention lack scientific backing. Studies suggesting a link are often flawed or misinterpreted.	Safe to consume for all populations, including the most vulnerable, with no risk of transmitting deadly milk-borne diseases.
Regulatory Status	Legality varies by state and country. Federal law bans interstate commerce of raw milk.	Sold legally and regulated for human consumption across the U.S. and in many countries.

Common Raw Milk Myths Debunked

Advocates of raw milk often spread misinformation to promote its consumption. It's crucial to address these falsehoods with scientific evidence:

Myth: Raw milk contains 'good' bacteria that aid digestion. The bacteria in raw milk are not probiotics added under controlled conditions like in yogurt. Their presence often indicates fecal contamination, and relying on them for gut health is both unproven and dangerous.
Myth: Pasteurization causes lactose intolerance. Lactose intolerance is caused by a lack of the lactase enzyme in the body, not by pasteurization. Both raw and pasteurized milk contain lactose and can trigger symptoms in sensitive individuals.
Myth: Raw milk is a cure for allergies. Research suggesting a link between raw milk and lower allergy rates typically studies children in farm environments with a wide range of microbial exposures. These studies do not prove a cause-and-effect relationship, and the risk of pathogens outweighs any potential benefit.
Myth: High-quality, clean farm practices eliminate the risk. While hygiene can reduce contamination, it can never eliminate it entirely. Bacteria can be shed from the animal's hide, udder, or feces and contaminate the milk, even from a healthy-looking cow.

Special Risks for Vulnerable Populations

While anyone can get sick from contaminated raw milk, certain groups face a significantly higher risk of severe illness or death:

Infants and young children: Their developing immune systems are more susceptible to severe and life-threatening infections.
Pregnant women: Infection with Listeria can lead to miscarriage, stillbirth, or neonatal infection.
The elderly: Weakened immune systems increase their vulnerability to serious complications from foodborne pathogens.
Immunocompromised individuals: Those with conditions like cancer, HIV/AIDS, or organ transplants are at much higher risk of life-threatening illness from pathogens commonly found in raw milk.

Conclusion

In conclusion, the documented dangers of drinking unpasteurized milk far outweigh its alleged benefits. Pasteurization remains a safe, effective public health measure that has dramatically reduced milk-borne diseases and is supported by decades of scientific evidence. The presence of harmful bacteria like E. coli, Salmonella, and Listeria in raw milk poses a real and unpredictable threat, particularly to vulnerable populations. While the allure of 'natural' foods is understandable, opting for pasteurized milk is the only way to ensure the safety of your dairy products and protect yourself and your family from potentially devastating illnesses. For comprehensive information on food safety and pasteurization, please consult authoritative sources like the U.S. Food and Drug Administration (FDA) at FDA.gov.

Note: If you suspect you have become ill from consuming raw milk, seek medical attention immediately.

Frequently Asked Questions

Raw milk is milk directly from an animal that has not been heat-treated to kill harmful bacteria. Pasteurized milk has been heated to a specific temperature for a set time to eliminate pathogens and is safe for consumption.

Yes, even milk from a healthy cow on a clean farm is not guaranteed to be safe. Pathogens can contaminate milk unpredictably from sources like the animal's feces or hide, and cannot be detected by sight or smell.

No, pasteurization does not significantly alter the nutritional value of milk. The levels of calcium, protein, and other key vitamins remain comparable to those found in raw milk.

Scientific studies have shown no difference in digestive symptoms between raw and pasteurized milk for individuals with lactose intolerance. Lactose is present in both types of milk.

Raw milk consumption has been linked to severe illnesses such as E. coli O157:H7 infection, Salmonella, Listeriosis, and Campylobacter, which can lead to kidney failure, paralysis, and death.

Boiling raw milk at home can kill harmful bacteria and is a method used in some regions where pasteurization is unavailable. This is the safest approach if consuming unpasteurized milk, but commercially pasteurized milk remains the most reliable option.

Leading public health organizations, including the Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA), strongly advise against drinking raw milk and recommend consuming only pasteurized milk and dairy products.