The Raw Revolution: Why Unpasteurised Milk is Making a Comeback

Supermarket dairy aisles offer a plethora of milk options, from whole, skimmed, and lactose-free, to alternatives like almond, oat, and soy. But there's one type of milk that we can’t find in supermarkets, and it’s gaining popularity.

You may not recall it, but you’ve probably heard about the famous Louis Pasteur in a primary school science class. Charmingly named after himself, In 1864, he coined the revolutionary concept of ‘pasteurisation’ - a process of heating food and beverages to a certain temperature for a set time to kill off any harmful microorganisms. By doing so, Pasteur was able to significantly extend the shelf life of a number of products without majorly impacting taste or quality. Originally used to help wine and beer preserve their flavour and appearance for longer, when German chemist Frans von Soxhlet suggested applying pasteurisation to milk more than twenty years later, Pasteur’s concept proved to be transformative well beyond the realms of food preservation.

This change in dairy processing quickly reduced the spread of diseases like typhoid, scarlet fever, diphtheria, tuberculosis, and various diarrheal illnesses, which were commonly contracted from contaminated unpasteurised milk. Before this, New York City witnessed alarming infant mortality rates, with one in every four infants dying due to contaminated raw milk in 1891. However, with the introduction of pasteurisation, this figure dropped significantly to about one in fourteen. And yet, despite its life-saving benefits, pasteurisation still faces criticism, with concerns over nutrient loss and altered taste sparking ongoing debate between advocates of ‘‘pure milk’’ (raw milk) versus ‘‘purified milk’’ (pasteurised milk).¹

How pasteurisation works

Today, the most common pasteurisation method involves heating milk to 62-73 degrees Celsius for at least 15 seconds to kill any pathogens picked up between milking and bottling. Inevitably though, even after pasteurisation, a small amount of harmless bacteria capable of spoiling milk may remain, so rapid cooling followed by refrigeration is crucial to prevent their spread. To reduce risk further, in many countries such as Spain, Belgium, France and China, another process called ultra-high temperature (UHT) treatment is more often used, also known as ‘ultra-pasteurisation’. This method goes even higher with temperatures (138–150 °C) for a short time (1-3 seconds), killing off more microorganisms, further increasing the shelf life, and eliminating the need for refrigeration until the carton is opened.^2,3

Despite UHT being the obvious choice for longer shelf life and lower bacterial load, which process countries opt for depends on a much wider set of cultural, legislative, logistical, and climate factors. In the United States, for example, UHT milk is still relatively uncommon, as Americans tend to prefer their milk fresh and cold, and have the infrastructure to support the large scale transport of cold refrigerated goods.⁴ In hotter regions with longer supply chains on the other hand, UHT may be preferred as a way to reduce spoilage and bring down refrigerated transport costs.

Raw milk skips pasteurisation altogether, and is instead bottled and refrigerated straight from the udder. This reduces shelf life significantly and increases the risk of milk borne illnesses if the raw milk is contaminated with pathogens.¹

The legal labyrinth of buying raw milk

In the US, federal law bans the sale of unpasteurised milk across state lines, but each state has its own rules for selling it within the state. And the states are far from cohesive in their regulations - twenty states have completely banned the sale of raw milk, while thirty allow it. Among those that allow it, seventeen only permit sales directly from farms. Additionally, eight of the states that ban raw milk sales still permit it, but only “cow-share” agreements, where multiple people collectively own one or multiple cows for the sake of obtaining milk or other products for personal consumption.^5,6 

In the EU however, things are slightly different. As it stands, EU hygiene regulations allow individual Member States to regulate the sale of raw milk for human consumption, with stringent and regular testing, and an emphasis on clear labelling to minimise any potential health risks. For example, some countries permit the sale of raw milk through vending machines, but only with labelling advising consumers to boil it before drinking. Other EU countries enable primary dairy producers to supply small quantities of raw milk directly to consumers, but only within a specified radius of the producing farm.^7,8

Due to a short shelf life, raw milk demands a radical shift in distribution chains, requiring farmers to organise short direct-to-consumer delivery circuits that reduces time in transport and by-passes retailers. 

Got (raw) milk?

In recent years, public interest in drinking raw milk has been growing in both the EU and the US. Today, it has been estimated that at least 3% of the US population consumes unpasteurised (raw) milk, and the demand to legalise raw milk sales continues to increase.⁹ This rise in popularity grows alongside a movement towards a more embracing view on the ‘natural’ and unprocessed, something epidemiologist Tim Spector supports in his best-selling book 'The Diet Myth'. Among Spector’s broad advice for us not to be too clean or fearful of exposure to bacteria, in the book he lamented the absence of properly regulated raw milk, emphasising the potential health benefits and nutritional value of unpasteurised.¹⁰

Spector isn’t alone in this either. The pro-raw narrative is now commonly echoed by many around the world. And given the fresh concerns about Ultra Processed Foods (UPFs) and the recognition of the importance of our gut microbiome, there is a growing preference for less processed dairy that retains the beneficial bacteria lost through pasteurisation. This makes raw milk an increasingly easy-to-sell choice, with supporters and online sources promoting raw milk as a natural, nutrient-dense drink full of probiotics that promote gut health. Some proponents even categorise it as a superfood, asserting its potential to improve digestion, boost immune response, and potentially alleviate symptoms associated with conditions such as allergies, eczema, and asthma.¹¹

Certain claims also suggest that the presence of Lactobacillus bacteria in raw milk, lost during pasteurisation, enables the digestion of lactose, making raw milk acceptable even for the lactose-intolerant among us. However, scientists have put this to the test and found no evidence supporting reduced lactose malabsorption or alleviation of lactose intolerance symptoms after consuming raw milk.¹²

The risks of going raw

While raw milk is not inherently unclean in itself, the likelihood of contamination poses significant issues. Even in relatively clean operations, without a dedicated and detailed approach to reducing bacterial risks, raw milk can easily become contaminated through a number of sources from bacteria on cow udders, to the hands of milkers themselves. And given the shorter shelf life of raw milk, even a small amount of bacteria can quickly become a big enough problem to cause serious illness. Symptoms include nausea, vomiting, stomach pain, fever, headache, and body aches. While most affected people would recover within days or weeks, severe symptoms can be life-threatening, especially for high-risk groups such as children and pregnant women.¹⁵ Furthermore, besides the possibility of harmful bacteria, raw milk also contains microbes that are resistant to antibiotics. This means that regularly consuming raw milk could lead to the spread of antibiotic resistance in the human gut.¹⁶

In response to the surging interest in raw milk, certain US states have eased regulations, allowing direct sales of raw milk to consumers. However, federal health authorities have raised concerns about a corresponding increase in foodborne illness outbreaks associated with raw milk consumption. Between 1998 and 2018, the Centers for Disease Control and Prevention noted a significant uptake in raw milk-related outbreaks nationwide, resulting in illness for 2,645 individuals, with 228 hospitalisations and three fatalities. And more specifically, from 2013 to 2018, states permitting retail sale of raw milk experienced three times more outbreaks compared to states where such sales were prohibited.¹⁴ 

In the EU, a scientific assessment of the public health risks linked to raw milk consumption by experts from The European Food Safety Authorities Panel on Biological Hazards cautioned that raw milk can harbour harmful bacteria like Campylobacter, Salmonella, and Shiga toxin-producing Escherichia coli (STEC). However, due to limited data, they couldn't precisely quantify these risks. Nonetheless, between 2007 and 2013, Member States reported 27 outbreaks of foodborne illness linked to raw milk consumption.⁸

Despite North America’s increased consumption of raw milk, better public awareness and improved hygiene during production has seen outbreak rates declining from 2010 to 2016. There are now dedicated raw milk producers, specifically qualified in the production of hygienically produced safe raw milk. Source: Epidemiol Infect Journal, 2020.

In saying all this, it’s worth recognising that the pasteurisation process is not always perfect either. Both milk and other pasteurised dairy products have caused outbreaks of milk borne diseases in the past, both in the EU and the US. Thankfully, tight farm regulations can serve as an additional line of defence. In the EU there are a set of rules to ensure hygienic production of food from animal origin (Reg. 853/2004). Within the dairy sector, particular emphasis is placed on ensuring the safety, quality, and composition of raw milk - the primary ingredient in most dairy products. According to these regulations, to prevent contamination, cows must be kept in clean conditions, dairy equipment and premises regularly sanitised, and protocols established for proper waste disposal.¹⁷

Moving past the debate

In current food safety debates, raw milk often steals the spotlight, especially in social media’s comment sections. But amidst the many passionate assertions, it's crucial to contextualise its hazards, as it's not the only food carrying health risks and certainly not the most significant. As mentioned earlier, between 1998 and 2018, raw dairy was linked to three deaths in the United States. In contrast, the consumption of oysters results in approximately 100 deaths annually in the US due to Vibriosis illness.¹⁸ This isn't to downplay the concerns associated with raw milk; as without the widespread adoption of pasteurisation practices, the casualties and health risks associated with raw milk would have likely been significantly higher.

So, what's the takeaway? I think that it is important to be curious and informed without getting caught up in the polarisation or politicisation of food debates. While the likelihood of getting sick from raw milk is small, it’s much smaller with pasteurised milk (and even smaller with a plant-based milk alternative).