Milk is best known as the go-to source for calcium, but it’s also packed with protein, vitamin D, and many other beneficial nutrients.1 Raw milk has seen some recent trends as a health food, but it may actually be dangerous. Learn more about the dangers of raw milk below.
What is Raw Milk?
Raw milk is simply milk that has not gone through the process of pasteurization. Pasteurization involves heating up a food product to kill off harmful germs and bacteria capable of causing illness. Pasteurization of milk started to prevent and reduce foodborne illnesses.
Many people drink raw milk because they believe that the pasteurization process kills off beneficial microorganisms and denatures beneficial proteins. However, even if some nutritional value is lost, the health risks of raw milk outweigh the benefits.2
The Dangers of Raw Milk
Raw milk can be dangerous to one's health. The biggest danger with raw milk comes from its potential to carry a variety of germs and bacteria, including:
- E. coli
Milk has a neutral pH, high nutritional content, and high-water content, all of which makes it an ideal environment for bacteria to thrive and spread. Although milk comes from a generally sterile environment in the animal, it is almost immediately presented with the potential of contamination after milking from the udder, feces, milking equipment, and general handling and storage.3 Some studies have found that about one-third of all raw milk samples contained pathogens, even when the samples came from clinically healthy animals.4
The bacteria in raw milk may also cause more severe illnesses such as:
1. Guillian-Barre Syndrome (GBS):
Infection with the Camplyobacter jejuni bacteria has been connected to Guillian-Barre syndrome, a condition caused by the immune function mistakenly attacking your own nerve cells, resulting in weakness, numbness, and even temporary paralysis.6
2. Hemolytic Uremic Syndrome (HUS):
Consuming raw milk that has been contaminated with Shiga toxin-producing E. coli O157:H7 has also been studied as a potential risk factor for hemolytic uremic syndrome.7 Hemolytic uremic syndrome results in low red blood cell levels (anemia), destruction of blood platelets, and potential kidney failure. Damage to the blood vessels can also affect functions in the brain and heart.8
Infection from contaminated raw milk resembles other food-borne illnesses and can result in a variety of symptoms, including:
- General abdominal pain
Any person is susceptible to the effects of harmful bacteria in contaminated raw milk, but the risk may be higher for:
- Children - Studies conducted by the Centers for Disease Control and Prevention found that about 59 percent of all outbreaks involved at least one child younger than the age of 5.9
- Pregnant women
- People with compromised immune systems5
Raw Milk Benefits
Why Do Some People Still Drink Raw Milk Despite the Dangerous Health Risks?
With all that said, if raw milk is collected under sanitary conditions that minimizes the chances of contamination with pathogens there are benefits to consuming it.
1. Raw Milk Protects Against Allergies
In a cross-sectional multi-center study, 14,893 children age 5 to 13 years old from five European countries were surveyed via a questionnaire, which included a dietary component. Results of the study showed that consumption of raw milk contributed to a decrease in asthma, seasonal allergies, and sensitivity to pollen, horse dander, and certain foods. This ultimately suggests that consuming raw milk may protect against asthma and certain allergies, though the underlying biological mechanism still requires study.10
Some studies suggest that raw milk contains immune-modulating proteins and other constituents that cannot be found in pasteurized milk that may contribute to protection from allergens. In bovine milk specifically, researchers isolated lactoferrin, lactadherin, lysozyme, and other milk proteins that could play a role in the immune-related functions linked to raw milk consumption.11
2. Raw Milk Contains Probiotics
Although raw milk may contain harmful bacteria, it may also contain probiotic microbes. Probiotics are the good bacteria that populate the gut’s microbiome and may offer a variety of benefits, from supporting immune functions to ensuring the proper break down and absorption of nutrients for good digestive health. Despite these benefits, taking raw milk with the risk of an infection is not worth it when one consumes probiotics through other safer means. Some examples of getting good probiotics is eating yogurt or taking a probiotic supplement.
3. Raw Milk Lowers the Chances of Developing Autoimmune Diseases (Allergies, Eczema, Asthma)
This all ties into the hygiene hypothesis. According to this scientific theory, the increased incidences of autoimmune and allergic diseases is caused in part by the decrease in exposure to microbial pathogens. 12
Various studies and data support the theory, though the underlying mechanisms of the hygiene hypothesis remain unclear. Increases in exposure to different bacteria, parasites, and bacteria, and gut bacteria is correlated with decreases in the autoimmune diseases. Patients with autoimmune disease have been observed to also suffer from dysbiosis, or microbial imbalance, in the gut, though researchers still have not developed a causal relationship between the two.14
The hygiene hypothesis still requires further study and remains confusing for parents. Some researchers recommend renaming the hypothesis instead to the “microbial exposure” hypothesis or “microbial deprivation” hypothesis, which helps focus more attention on the effects of pathogens on autoimmune diseases instead of discouraging good hygiene practices.15
Safer Alternatives to Raw Milk
As mentioned, pasteurized milk still offers plenty of nutritional benefits. Most prominently, milk is an excellent source of calcium, the primary component in your bones and teeth, and vitamin D, which helps calcium absorption and regulates calcium levels. When combined, calcium and vitamin D can help to build strong bones and combat diseases that contribute to weak bones, like osteoporosis.16
Along with calcium and vitamin D, cow’s milk contains:
- Protein (maintains bones and promotes muscle growth)
- Iodine (maintains skin health, metabolism, and functions of the nervous system)
- Potassium (maintains blood pressure, muscle function, and nervous system function)
- Phosphorous (promotes bone development and maintains metabolism and cell membrane function)
- Vitamin B2 (maintains vision, metabolism, and red blood cell function and prevents fatigue and tiredness)17
While you may not get the immune-modulating proteins found in raw milk, you can still get many of the probiotics without consuming raw milk. The safer option is to drink pasteurize milk and then add known beneficial bacteria back into it.
A popular example of this is yogurt, which comprises milk that has been pasteurized and then fermented with the addition of live and active bacteria cultures. The basic cultures used in yogurt are Lactobacillus bulgaricus and Streptococcus thermophilus, though some manufacturers will add more probiotic cultures, including Lactobacillus acidophilus, Lactobacillus casei, and Bifidus. When added to the pasteurized milk, these bacteria consume the lactose, or natural sugar in the milk, and release lactic acid as a by-product. Lactic acid provides the distinct tart flavor in yogurt while also creating the thick, creamy texture.18
Kefir is another fermented dairy drink, though instead of bacteria cultures, kefir is fermented with what’s known as “kefir grain,” which comprises both bacteria and yeasts. Milk is combined with these bacteria and yeasts and left in a warm area to ferment, producing kefir. Kefir has a tart, tangy flavor and may taste slightly carbonated.19 Kefir offers many of the same vitamins and nutrients as yogurt, but it may be an even richer source of probiotics than yogurt, containing about 30 different strains of yeasts and bacteria.20
For children, probiotic supplements offer a more diverse and powerful source of the beneficial bacteria. It is recommended that children suffering from diarrhea or other digestive issues should take 10 billion CFUs or more of probiotics to reduce the duration of active diarrhea.21
Further studies, research, and technological improvements need to be done to potentially make raw milk safer for consumption. Maybe one day, we can isolate the beneficial components of raw milk or eliminate the harmful pathogens in milk without reducing the nutrients, probiotics, enzymes, or proteins. Until then, you can still enjoy the health benefits of pasteurized milk or incorporate more probiotics into your diet.