January 2025 Issue
Ask the Expert: Raw Milk
By Toby Amidor, MS, RD, CDN, FAND
Today’s Dietitian
Vol. 27 No. 1 P. 6
Debunking This Misrepresented Online Trend
Q: My clients have been asking about the health benefits of drinking raw milk. Is there any science for health benefits of raw milk consumption?
A: Raw milk consumption has been gaining popularity, especially on social media. Sales of raw milk have increased 21% to 65% since 2023, according to data from NielsenIQ.1 The FDA claims that less than 1% of Americans have rejected pasteurization in favor of raw milk, citing taste, the nutritional and health benefits of raw milk consumption, and a preference for unprocessed food.2 Furthermore, there are inaccurate health claims of raw milk consumption being spread, including its ability to cure allergies and enhance immunity. The following will explore the food safety concerns of raw milk consumption, the nutritional comparison between raw and pasteurized cow’s milk, and the data regarding the health claims.
Food Safety Concerns
Pasteurization—the elimination of pathogenic bacteria by heat treatment—of milk was adopted decades ago as a public health measure to eliminate the risk of illness from a staple food in the American diet. In 1987, the CDC prohibited the interstate sale of raw milk, and today, 20 states prohibit intrastate raw milk sales, while 30 allow it.2
Raw milk consumption is the greatest concern among high-risk populations such as children, people who are immunocompromised, pregnant and lactating women, and older adults, as the risk of illness or death can result.2 Since 1987, there have been 143 reported outbreaks of illness that resulted in miscarriages, stillbirths, kidney failures, and death due to raw milk products contaminated with pathogenic bacteria such as Listeria, Campylobacter, Salmonella, and E. coli. The risk isn’t only by consumption; illnesses like E. coli can also be spread between humans. Additional symptoms of raw milk consumption can include diarrhea, stomach cramping, and, in more severe cases, Guillain-Barre syndrome or hemolytic uremic syndrome, potentially leading to paralysis, kidney failure, stroke, or death.3
Nutrition Quality
Studies have shown that pasteurization has minimal impact on the nutritional quality of milk. The total protein of cow’s milk is ~3% to 3.5%, with 80% casein and 20% whey proteins. Research reveals that the protein quality of pasteurized vs raw milk is not different.4 Research for milk fat is no different as cow’s milk contains 3% to 4% milk fat, with the remaining fat existing as triglycerides.
A 1973 study found that pasteurization has no effect on milk fat composition.5 Research conducted on the homogenization of milk and its effects on nutritional composition6,7 concluded that homogenized milk seems more digestible compared with raw milk. The researchers also suggested that since homogenization released milk fat globule membrane components, the function of some bioactive components in the milk fat globule membrane may be enhanced.7 With mineral composition, the bioavailability of calcium is the same in raw and pasteurized milk,8 while an in vitro study showed that the bioavailability of zinc and selenium wasn’t affected by pasteurization or sterilization.9
Health Claims
Although numerous raw milk misconceptions exist, this section will focus on the belief that raw milk can cure or treat allergies and enhance the immune system.2 Both animal research and human clinical trials have shown that raw and pasteurized milk don’t differ in their anaphylactic-sensitizing capacity.10,11 One human study compared the response in children allergic to cow’s milk when they consumed raw, pasteurized, and homogenized/pasteurized milk. All children developed significant and similar allergic reactions when they consumed any of the forms of milk.11
Some believe raw milk can help build the immune system; some parents and caregivers even serve raw milk to young children and infants. However, children are more vulnerable compared with healthy adults to the pathogens found in raw milk. There are many cases showing
the negative consequences of children
consuming raw milk. For example, in
2008, 14 people in Connecticut became ill
with E. coli 0157:H7 by drinking raw milk.
The most seriously ill were three children,
and two developed hemolytic uremic syndrome.
12 Raw goat’s milk can also be contaminated,
like in Colorado in 2010 when
24 people became sick from consuming
goat milk contaminated by Campylobacter
and E. coli O157:H7—two children
were hospitalized.13 In 2024, in Washington,
two people in different counties
became ill with Campylobacter jejuni after
drinking contaminated raw milk sold at a
local creamery.14
A 2020 in vitro study published in the
Journal of Dairy Research examined if the
consumption of raw or unprocessed cow’s
milk contributes to lowered prevalence
of allergies.15 Denaturation of bovine
serum albumin, immunoglobulin G, and
lactoferrin in skim milk was studied under
different temperature (72, 75, or 78˚C) and
time (0 to 300 seconds) combinations.
Through gel electrophoresis, the results
revealed that denaturation of all three
proteins occurred at 72˚C and progressed
with increased temperature and holding
time. About 59% of lactoferrin and 12%
of immunoglobulin G denatured under
high-temperature, short-time (72˚C/15
s) pasteurization, while bovine serum
albumin was least impacted. While this
study is informative, it only looks at a
few specific responses to the proteins
and not a complete immune response
as seen in the body. Animal and human
studies would be required to observe
any impact on immunity. In addition,
an examination of the full complement
of nutrients in milk that are linked to
immune support, as well as the whole
matrix effect, should be examined.
Recommendation for RDs
Dietetic professionals should adhere to
the CDC guidelines, which recommend
people choose pasteurized milk and dairy
products. In addition, remind clients to
refrigerate pasteurized milk and dairy
foods at 40˚ F or below to slow bacterial
growth, as bacteria can quickly multiply
if left at temperatures between 40 and
140˚ F. If dairy is left out for more than two
hours (or one hour if the temperature is
90˚ F or above), it should be discarded.
If a client insists on purchasing raw
milk, dietetic professionals should explain
the health risks involved and warn the client
of the increased risk to older adults,
pregnant and lactating women, immunocompromised
individuals, and children.
— Toby Amidor, MS, RD, CDN, FAND, is founder of Toby Amidor Nutrition (tobyamidornutrition.com) and a Wall Street Journal bestselling author. She’s written 11 cookbooks, including Health Shots: 50 Simple Tonics to Help Improve Immunity, Ease Anxiety, Boost Energy, and More. She’s also an award-winning media dietitian, spokesperson, and nutrition expert for FoodNetwork.com, and a contributor to U.S. News and other national outlets.
Send your questions to Ask the Expert at TDeditor@gvpub.com or send a tweet to @tobyamidor.
References
1. Aleccia, J. Raw milk sales spike despite CDCs warnings of risk associated with bird flu. PBS News website. https://www.pbs.org/newshour/health/raw-milk-sales-spike-despite-cdcs-warnings-of-risk-associated-with-bird-flu. Published May 14, 2024.
2. Food safety and raw milk. FDA website. https://www.fda.gov/food/buy-store-serve-safe-food/food-safety-and-raw-milk. Published March 5, 2023.
3. Raw milk. CDC website. https://www.cdc.gov/food-safety/foods/raw-milk.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Ffoodsafety%2Frawmilk%2Fraw-milk-index.html. Published April 29, 2024.
4. Andersson I, Oste R. Nutritional quality of heat processed liquid milk. In: Fox PF, ed. Heat-Induced Changes in Milk. Brussel, Belgium: International Dairy Federation; 1995:279-307.
5. Rolls BA, Porter JWG. Some effects of processing and storage on the nutritive value of milk and milk products. Proc Nutr Soc. 1973;32(1):9-15.
6. Michalski M. On the supposed influence of milk homogenization on the risk of CVD, diabetes and allergy. Br J Nutr. 2007;97(4):598-610.
7. Michalski M, Januel C. Does homogenization affect the human health properties of cow's milk? Trends Food Sci Technol. 2006;17(8):423-437.
8. Weeks CE, King RL. Bioavailability of calcium in heat-processed milk. J Food Sci. 1985;50(4):1101-1105.
9. Van Dael P, Shen LH, Deelstra H. Influence of milk processing on the in vitro availability of zinc and selenium from milk. Paper presented at: Nutrient Bioavailability Symposium of the Federation of European Chemical Societies; 1993; Belgium.
10. Poulsen OM, Hau J, Kollerup J. Effect of homogenization and pasteurization on the allergenicity of bovine milk analysed by a murine anaphylactic shock model. Clin Allergy. 1987;17(5):449-458.
11. Host A, Samuelsson EG. Allergic reactions to raw, pasteurized, and homogenized/pasteurized cow milk: a comparison. Allergy. 1988;43(2):113-118.
12. Legislature must rein in risk of raw milk. FoodHACCP website. http://www.foodhaccp.com/1news/040309a.html. Published April 3, 2009.
13. Bottemiller H. 24 ill in Colorado raw milk outbreak. Food Safety News website. https://www.foodsafetynews.com/2010/07/24-ill-in-colorado-raw-milk-outbreak. Published July 6, 2010.
14. Campylobacteriosis outbreak linked to raw milk consumption. Washington State Department of Health website. https://doh.wa.gov/you-and-your-family/illness-and-disease-z/foodborne-illness/outbreaks/2024-campylobacteriosis-raw-milk. Updated August 12, 2024.
15. Bogahawaththa D, Vasiljevic T. Denaturation of selected bioactive whey proteins during pasteurization and their ability to modulate milk immunogenicity. J Dairy Res. 2020;87(4):484-487.