What milk is unprocessed? A guide to raw milk and its safety debate

October 21, 2025 •

4 min read

The Centers for Disease Control and Prevention (CDC) attributes hundreds of illnesses and dozens of hospitalizations each year to the consumption of unpasteurized milk. The question of what milk is unprocessed is at the center of a long-standing debate among dairy consumers regarding perceived benefits versus significant health risks.

Quick Summary

Unprocessed milk, or raw milk, has not been heat-treated to eliminate harmful bacteria, posing potential food safety hazards. This article examines the differences between raw and pasteurized milk, explores the nutritional controversies, and outlines the documented dangers of consuming unpasteurized dairy products.

Key Points

Raw Milk is Unprocessed: Raw milk has not been pasteurized, meaning it has not been heated to kill potentially harmful bacteria.
Significant Health Risks: Raw milk can contain dangerous pathogens like E. coli, Salmonella, and Listeria, which can cause serious, even life-threatening, illnesses.
No Proven Nutritional Advantage: Scientific studies show no significant nutritional difference between raw and pasteurized milk, debunking many claims of superior health benefits.
Vulnerable Populations are at High Risk: Children, the elderly, pregnant women, and immunocompromised individuals face a much higher risk of severe illness from raw milk contamination.
Pasteurization Ensures Safety: Health authorities strongly recommend pasteurized milk, as this process effectively eliminates the risk of foodborne illness.
Legal Status Varies by State: In the U.S., federal law prohibits the interstate sale of raw milk, and state-level regulations differ, with some banning sales entirely while others allow limited options.

Understanding the Unprocessed Debate: Raw Milk Defined

When consumers ask, "What milk is unprocessed?" the answer is raw milk. Raw milk is milk that comes directly from a cow, goat, sheep, or another animal without undergoing pasteurization, a heat-treatment process designed to kill harmful bacteria. The debate around raw milk consumption is complex, pitting personal choice and anecdotal claims of health benefits against the scientific consensus on food safety and public health. While advocates claim a superior nutritional profile and unique enzymes, health authorities like the FDA and CDC stress the serious dangers of foodborne illness.

The Function of Pasteurization

To fully understand unprocessed milk, it is important to know why most milk on the market is processed. Pasteurization was invented by Louis Pasteur in the 19th century and has since become a standard food safety practice for milk worldwide.

How Pasteurization Works

Pasteurization involves heating milk to a specific temperature for a set period of time. This process effectively kills disease-causing germs that can be present in raw milk, including Salmonella, E. coli, and Listeria. There are a few different methods used:

High-Temperature Short-Time (HTST): The most common method, heating milk to 72°C (161°F) for 15 seconds.
Ultra-High Temperature (UHT): Heating milk to 138°C (280°F) for at least two seconds, giving it a much longer shelf life.
Batch (Vat): Heating milk to a lower temperature, around 63°C (145°F), for at least 30 minutes, which is an older and less common method.

The Significant Risks of Consuming Raw Milk

For most food safety experts, the risks of drinking raw milk far outweigh any purported benefits. Raw milk can become contaminated in various ways on the farm, even with the best hygienic practices. Contamination can come from cow feces, the animal's udder, or the milking equipment.

Potential Pathogens and Illnesses

The most serious concern with raw milk is the presence of harmful bacteria, which can cause severe illness. These include:

Campylobacter: A common cause of diarrheal illness.
Salmonella: Can cause fever, diarrhea, and abdominal cramps.
Listeria monocytogenes: A bacterium that is particularly dangerous for pregnant women, newborns, and immunocompromised individuals, potentially leading to miscarriage, stillbirth, or death.
Escherichia coli (E. coli): Certain strains, like O157:H7, can cause severe and bloody diarrhea, and in some cases, life-threatening kidney failure.
Avian Influenza (H5N1): Recent outbreaks have shown that the H5N1 virus can be present in high concentrations in raw milk from infected cattle, though pasteurization effectively inactivates it.

The Nutritional Claims vs. Scientific Evidence

Advocates for unprocessed milk often claim that pasteurization destroys beneficial enzymes and nutrients, and that raw milk contains helpful probiotic bacteria. However, these claims are not supported by robust scientific evidence.

Raw vs. Pasteurized Milk: A Comparative Look


Feature	Raw Milk (Unprocessed)	Pasteurized Milk (Processed)
Safety	High risk of carrying harmful bacteria.	Low risk of foodborne illness.
Nutritional Value	Claims of superior nutrition lack scientific backing. Contains same key nutrients.	Retains almost all key nutrients, with minimal loss of heat-sensitive vitamins. Often fortified with Vitamins A and D.
Beneficial Bacteria	May contain some beneficial bacteria, but also dangerous pathogens.	No live bacteria, good or bad, are present due to heat treatment.
Enzymes	Contains naturally occurring enzymes, some of which are heat-sensitive.	Most heat-sensitive enzymes are denatured during pasteurization.
Digestibility	Claimed to be easier to digest for those with lactose intolerance, but scientific evidence is inconclusive.	Digestibility is not significantly different; lactose content is the same.
Shelf Life	Shorter shelf life due to microbial activity.	Longer shelf life due to the killing of spoilage-causing bacteria.

The Complex Legalities of Raw Milk

In the United States, the interstate sale and distribution of raw milk for human consumption is prohibited by the FDA. However, regulations for intrastate (within-state) sales are determined by individual states and vary widely.

Common intrastate sales regulations include:

Retail Sale: Legal in some states, allowing raw milk to be sold in stores.
On-Farm Sales: Legal in many states, requiring customers to purchase directly from the farm.
Herdshare Agreements: Legal in some states where direct sales are prohibited, allowing individuals to buy a 'share' of an animal to legally receive its milk.
Complete Prohibition: In some states, all sales of raw milk for human consumption are banned.

For a detailed overview of regulations by state, consult resources like the Farm-to-Consumer Legal Defense Fund map, which tracks raw milk laws across the US. The varying laws highlight the ongoing conflict between consumer choice and public health protections.

Conclusion: Making an Informed Choice

When considering your dietary choices, it is important to be fully informed about the facts and risks associated with unprocessed milk. While raw milk advocates highlight its natural state and anecdotal benefits, these claims are not backed by scientific consensus. The scientific community, including major health organizations like the CDC and FDA, overwhelmingly recommends consuming pasteurized milk to eliminate the risk of potentially deadly foodborne illnesses. The risk of bacterial contamination in raw milk, which can occur even under strict hygienic conditions, represents a serious threat to public health, especially for vulnerable populations. For a safe and nutritious dairy option, pasteurized milk remains the recommended choice, offering a reliable source of protein, calcium, and other essential nutrients without the significant health hazards associated with its unprocessed counterpart.

Frequently Asked Questions

The key difference is that raw milk is unprocessed and has not been heated to kill bacteria, while pasteurized milk has been heat-treated for a specific time and temperature to eliminate harmful pathogens, making it safer for consumption.

Despite claims by raw milk advocates, scientific studies have shown no significant nutritional difference between raw and pasteurized milk. Pasteurized milk retains almost all its nutritional value, and any minimal loss of heat-sensitive vitamins is not considered nutritionally significant.

No. Even milk from a seemingly healthy cow can carry harmful bacteria. Raw milk can be contaminated during milking or collection from the cow's udder, and good hygiene practices, while important, cannot eliminate the risk of pathogens.

Health authorities have found live, infectious H5N1 virus in raw milk from infected cattle. While pasteurization effectively inactivates the virus, raw milk can contain it, making it a potential public health risk.

Some studies have found a correlation between raw milk consumption in childhood and lower rates of allergies and asthma, particularly in farm-dwelling children. However, researchers note this is an association, not a proven cause, and the lower rates may be due to other farm-related exposures. The known risks of bacterial illness are considered to outweigh these potential benefits.

Yes, regulations vary. The FDA prohibits the sale of raw milk across state lines for human consumption. Within states, laws differ, ranging from on-farm sales and herdshare agreements to outright bans on all raw milk sales.

Some anecdotal reports suggest this, but scientific studies have found no evidence that raw milk improves digestion for people with lactose intolerance. Raw milk contains the same amount of lactose as pasteurized milk and can cause similar digestive symptoms.