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Raw Milk: Health Risk or Health Benefit?

  • Writer: FibonacciMD
    FibonacciMD
  • Mar 25
  • 6 min read

Is raw milk a healthier, more natural choice, or does it pose unnecessary health risks? We explore the science behind pasteurization and the claims surrounding raw milk's benefits and dangers.

Culinary Medicine


raw milk

Raw milk is milk straight from the cow. The “regular” milk we buy at the grocery store has been treated by a process, called pasteurization, which heats the milk to kill disease-causing microbes. Before pasteurization became the norm, about a quarter of foodborne illnesses in the United States were related to consumption of dairy products.[1]  Now that most of the milk sold in the U.S. is pasteurized, less than 1% of foodborne illness outbreaks are traced to dairy consumption and 70% of these cases are linked to unpasteurized milk.[1] Despite this, raw milk sales are on the rise.[2] Proponents suggest that pasteurization alters the flavor, nutrient content, and health benefits of raw milk.


History of Pasteurization

Pasteurization was developed in the 1860s by Louis Pasteur to preserve wine and was later adapted for other liquids, including milk. [3] In the U.S. today the most common method of pasteurization heats milk from cows, sheep, and goats to 161° F for 15 seconds.[4] This combination of heating time and temperature is designed to kill pathogens while minimizing alterations in taste or nutritional composition.


Milk was first pasteurized in the United States in the 1890s but pasteurization did not become widespread until passage of the 1924 Standard Milk Ordinance.[5]   Regulation of the production, processing, and sale of milk has expanded since the 1920s; in 1987 the FDA mandated pasteurization of all milk sold or distributed across state lines.[6]  Milk sales within states however are regulated at the state level.[7] Some states allow the sale of raw milk from retail outlets, others only allow sales at farms or farmer’s markets. And some only allow sales through a cow or herd share, which is an agreement that requires customers to buy a share of a cow or herd to purchase the milk. Only a few states completely restrict the sale of raw milk.


Health Claims and Scientific Evidence

Some people choose raw milk because they prefer natural, unprocessed foods or are looking for the latest superfood to improve their health. Others just do not want to be told what to do and consider mandatory pasteurization government overreach. Proponents of raw milk argue that pasteurization affects milk’s flavor, reduces its nutrient content, and compromises its health benefits.


Milk that comes right from the cow does have a creamier texture and sometimes a sweeter taste than milk from the grocery store. But these differences are not related to pasteurization. Milk straight from the cow is creamier because it has about 4% fat while the standard for whole milk sold in stores in the US is 3.25% fat. [9] Some raw milk has a sweet taste depending on the breed of cow and what she ate. Milk from grocery stores is often pooled from multiple sources; this blunts differences in flavor due to breed and feed. Pasteurization as well as processing and packaging may cause slight changes in flavor.


raw milk

Despite claims that pasteurization destroys nutrients, pasteurized milk does not significantly affect levels of the key nutrients that milk provides in the American diet. Milk is a reliable source of protein and neither the amount nor quality of the protein are altered by pasteurization. Likewise, milk provides calcium, phosphorus, and other minerals; heat heat does not change the content and bioavailability of the minerals. Pasteurization also does not affect the fat-soluble vitamins A, D, E, and K. In fact, pasteurized milk is much higher in vitamin D because it is fortified; raw milk only contains trace amounts. The water-soluble vitamins that are plentiful in milk, riboflavin, and vitamins B6 and B12, are only minimally affected by pasteurization. The only vitamin that is significantly degraded by heat is vitamin C, but milk is not a significant source for this vitamin.[10]


There is no evidence that pasteurization destroys health-promoting compounds in raw milk that help digestion and immunity. Although raw milk does contain enzymes that facilitate milk digestion by breaking down protein and fat, so does pasteurized milk. These enzymes are not affected by the heat treatment of pasteurization, but they are destroyed in the acidic environment of the stomach before the milk can move to the intestine for digestion.[10] Raw milk devotees claim that pasteurization destroys the natural antimicrobial properties of milk as well as factors that promote immunity. There are enzymes in raw milk that have antimicrobial properties, but levels are too low to kill pathogens. There are also antibodies in raw milk, but the concentration of these is too low to have an impact on human health and the predominant fraction is heat stable so it is not affected by pasteurization. [10]


Raw-milk enthusiasts also claim that unpasteurized milk is healthier because it does not cause milk allergies and reduces the symptoms of lactose intolerance. There is no evidence to suggest that raw milk is less allergenic than pasteurized milk; those allergic to milk should avoid all milk. [10] The idea that raw milk reduces symptoms of lactose intolerance is also not substantiated. Lactose intolerance causes gas, bloating, and diarrhea due to the inability to completely digest the milk sugar lactose, which is found in both raw and pasteurized milk. Advocates claim that raw milk contains probiotic bacteria that secrete the enzyme lactase, which breaks down lactose before it can cause symptoms. However, there is no evidence that raw milk contains either probiotic bacteria or lactase. [10]



Raw Milk and the Risk of Foodborne Illness

Consuming raw milk increases the risk of foodborne illness from pathogens such as Salmonella, E coli, Listeria, and Campylobacter. The risks of getting sick are greatest in pregnant women, babies, older adults, and anyone with a weakened immune system. Milk can be contaminated from infected cows as well as from contact with machinery, feces, insects, other animals, or humans. [6] Because raw milk typically comes from cows on a single farm advocates argue that the milk is safe if the cows are healthy and the farm is clean.[11] In contrast, milk sold in grocery stores is usually pooled from multiple farms so one infected cow can contaminate hundreds of gallons of milk, making pasteurization, which kills the pathogens, essential. Raw milk proponents contend, however, that even pasteurized milk is a risk because it can be contaminated after pasteurization. Although it is true that some foodborne illness is caused by mishandled pasteurized milk, the frequency of illness is far less than with raw milk.[12] Unpasteurized dairy products cause over 800 times more illnesses and 45 times more hospitalizations than pasteurized products. [13,14] And new risks are emerging. In March of 2024, the H5 N1 Avian flu virus was detected in dairy cattle. High titers of infectious virus have been found in milk from infected cows. The impact of ingesting the virus is still unknown, but it has been shown that pasteurization inactivates the virus.[15]


Bottom line

Social media influences, antiestablishment sentiments, and a desire to return to simpler times, contribute to the appeal of raw milk: a whole, unprocessed food that promises to taste better and be healthier than pasteurized milk. However, pasteurization does not cause significant changes in the taste, nutrient content, or health benefits of milk and both the CDC and FDA advise against consuming raw milk. Despite the allure of an all-natural alternative, consumers should consider the risk of serious illness posed by unpasteurized milk.



Editor’s note- Having worked on my friend’s two hundred cow dairy farm for two years I still cherish the taste of their fresh but pasteurized, non-homogenized milk. They now sell directly to consumers and to grocery stores.



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