Despite an ongoing outbreak of bird flu in dairy cows, the popularity of raw milk has only increased. Advocates claim that raw milk has better health benefits than pasteurized milk. There is little evidence to support these claims, however, and the risk of serious illness is greater.
Mississippi State University food scientists Juan Silva and Joel Komakech and nutritionist Mandy Conrad explain the difference between pasteurized and raw milk, addressing common misconceptions about the health risks and purported benefits of consuming unpasteurized milk. These questions are more important than ever, as cattle can shed viral material into their milk. Not only can pathogens spoil milk, but three farm workers are reported to have contracted H5N1, the virus that causes bird flu, in 2024. Farm workers can get sick by handling infected animals or their byproducts, such as raw milk.
What is pasteurization? Does it destroy nutrients?
Pasteurization is a process of heating beverages and foods at high temperatures – above 145 degrees Fahrenheit (62.78 degrees Celsius) – to kill harmful microorganisms, such as bacteria, viruses and parasites. This reduces the total number of microorganisms in the product and deactivates enzymes that can contribute to spoilage.
The process does not significantly affect the taste, nutritional value and quality of pasteurized products.
Although pasteurization can result in some nutrient losses, the changes are usually minimal and outweigh the benefits. Pasteurization tends to cause minor denaturation of proteins and has little effect on fats and carbohydrates. Although water-soluble vitamins such as vitamin C and some B vitamins, which are not abundant in milk except vitamin B2, can be partially degraded during pasteurization, fat-soluble vitamins (A, D, E and K, found in amounts significant in milk) more heat stable and suffering minimal loss.
Thus, the nutritional losses in milk due to pasteurization are generally small compared to the significant benefits of reducing foodborne illness and spoilage.
Is raw milk healthier than pasteurized milk?
Studies have compared the benefits of raw and pasteurized milk and found little evidence that raw milk is better than pasteurized milk. The perceived benefits of raw milk outweigh its health risks.
First, raw milk does not improve lactose intolerance.
Raw milk also does not have more vitamins than pasteurized milk. Milk is not a good source of vitamin C or other heat-sensitive vitamins, and pasteurization does little to reduce vitamin B2 or riboflavin, which are less heat-sensitive. In addition, Vitamin D is added to pasteurized milk to increase your body’s ability to absorb the calcium in milk.
Fortified milk replaces nutrients that may be lost in the pasteurization process. Vitamin D is added to milk to increase the absorption of the calcium found in the milk. No one food is perfect, so it’s okay for milk to lack nutrients, as these can be obtained from other foods.
Some people believe that probiotics – foods or supplements containing live bacteria that benefit health – are more prevalent in unpasteurized milk and products made from raw milk. However, raw milk is generally lacking in probiotics and contains far more harmful bacteria. Probiotics are added to many dairy foods such as yogurt after pasteurization.
Additionally, a 2011 review of the available research on the health benefits of raw milk found that many of these studies had weak methods, meaning their results should be interpreted with caution. .
What are the health risks of consuming raw milk?
The health risks associated with consuming raw, unpasteurized milk come from harmful micro-organisms that may be present.
Raw milk has been linked to hundreds of outbreaks of foodborne illness. Between 1998 and 2018, 202 outbreaks resulted in 2,645 illnesses and 228 hospitalizations. Later, from 2022 to 2023, there were 18 outbreaks and recalls involving raw milk. Several outbreaks and recalls related to pathogens in raw milk have already occurred in 2024. In all cases, the pathogens in raw milk that cause human disease were directly responsible for these illnesses.
Some illnesses from the pathogens in raw milk can have serious long-term consequences, including paralysis, kidney failure and death.
Researchers found that there were more than three times more outbreaks in areas where raw milk was sold legally in the US from 1998 to 2018 than in areas where it was illegal to sell raw milk. Areas where raw milk was allowed to be sold in retail stores had almost four times more outbreaks than areas where only farm sales were allowed.
Is it safe to eat foods made from raw milk?
Many, if not all, dairy products made from unpasteurized milk are not safe to eat. A number of products can be made from raw milk, including soft cheeses, such as brie and Camembert; soft Mexican-style cheeses, such as queso fresco, panela, asadero and queso blanco; yogurt and puddings; and ice cream or frozen yogurt. Pathogens in raw milk can survive the processes involved in making these types of dairy products and are therefore not safe for consumption.
Only products that undergo a process to prevent or kill harmful microorganisms can be safe enough to be made from unpasteurized milk. However, there is the potential for cross-contamination of raw and cooked food as well as the survival of pathogens from inadequate processing when products are made with raw milk.
Can pasteurized milk still make you sick?
The few reported outbreaks involving pasteurized milk can be traced to contamination after pasteurization. When handled properly, pasteurized milk is a very safe product.
The US government requires farmers to destroy milk from flocks infected with bird flu. As of June 2024, 12 states have reported flocks testing positive for H1N5, the virus that causes bird flu.
There is currently no evidence that people get sick from consuming pasteurized milk from infected cows. Based on the available evidence, the Food and Drug Administration currently states that pasteurization is capable of destroying or inactivating heat-sensitive viruses such as H5N1 in milk.
There may be a risk of disease transmission to humans if raw milk is consumed.
Can you get immunity from H5N1 from drinking raw milk?
Some people believe that drinking raw milk can strengthen their immune system. However, there is no scientific evidence to support that drinking raw milk can improve immunity against disease.
Vaccines train your body to protect itself from future infections without actually getting sick from that infection. They do this by exposing your immune system to very small amounts of a dead or significantly weakened pathogen.
Raw milk contains live H5N1 virus, which means it can still infect you and make you sick. Besides boosting your immunity, raw milk exposes you to the virus in full force and can lead to severe illness. Any protective antibodies that may be present in raw milk are likely to be degraded in stomach acid.
In addition, people who get bird flu from raw milk run the risk of transmitting it to other people or animals by giving the virus a chance to adapt and improve its ability to spread between people. This increases the risk of more widespread disease outbreaks.
This article is republished from The Conversation, a non-profit, independent news organization that brings you facts and analysis to help you make sense of our complex world.
It was written by: Juan Silva, Mississippi State University; Joel Komakech, Mississippi State Universityand Mandy Conrad, Mississippi State University.
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The authors do not work for, consult with, or own shares in, or receive funding from, any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.