The claim: Drink raw milk
Is raw milk healthier or safe?
Against, and the risk is measured. Evidence grade: Probable.
Published Updated
The book tests this claim twice, in a table and in the chapter that owns the subject. Both verdicts are below, each with its own evidence and sources.
Chapter 2's table of nine claims: "Drink raw milk"
Against, and the risk is measured
The evidence
Unpasteurized milk and cheese are eaten by a small minority of Americans, yet they accounted for 96% of the illnesses from dairy outbreaks (Chapter 6).19
The "What you've heard" box in Chapter 6: "Raw milk is healthier"
Unsupported, and the risk is measured
The evidence
In a large European study of farm children, drinking farm milk was linked to less asthma. But the link was observational, and boiled farm milk showed no such link. The infection risk, by contrast, is counted. In the United States, a small minority of people drink raw milk or eat unpasteurized cheese, yet unpasteurized dairy caused 96% of the illnesses in dairy-linked outbreaks. Raw milk can carry Listeria, E. coli and other germs most dangerous to young children, pregnant women, older adults and anyone with weakened immunity.14
Where the book tests it
What the book recommends instead
Settle the dairy question with a two-week trial, not a DNA kit
ProbableEvidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.How: if milk reliably brings bloating, gas or cramps, switch to lactose-free dairy, or take a lactase enzyme with dairy, for two weeks. Then drink ordinary milk again on purpose and see what happens. Fermented dairy such as yogurt is often fine when milk is not. Why: losing lactase after childhood is the normal state for most adults on earth. Persistent gut symptoms still deserve a doctor, since celiac disease and inflammatory bowel disease can imitate lactose trouble.
Related claims
- Do probiotic pills fix your gut?For healthy people, unsupported; spend the money on yogurt and beans.Evidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.
- Can a greens powder replace vegetables?Expensive vitamins, and no substitute for vegetables.Evidence grade: Emerging. Early, small, animal-only, or actively contested.
- Is leaky gut real?Real in specific diseases, unproven as an everyday diagnosis.Evidence grade: Emerging. Early, small, animal-only, or actively contested.
Sources
Chapter 2's table of nine claims
- 19.Costard, S., Espejo, L., Groenendaal, H., and Zagmutt, F.J. (2017). "Outbreak-related disease burden associated with consumption of unpasteurized cow's milk and cheese, United States, 2009-2014." Emerging Infectious Diseases, 23(6), 957-964. https://doi.org/10.3201/eid2306.151603 (raw milk is consumed by 3.2% and unpasteurized cheese by 1.6% of the US population)
Note numbers are those of Chapter 2, What Your Body Expects, and How to Trust This Book.
The "What you've heard" box in Chapter 6
- 14.Loss, G., Apprich, S., Waser, M., Kneifel, W., et al. (2011). "The protective effect of farm milk consumption on childhood asthma and atopy: the GABRIELA study." Journal of Allergy and Clinical Immunology, 128(4), 766-773.e4. https://doi.org/10.1016/j.jaci.2011.07.048 (8,334 rural schoolchildren); Costard, S., Espejo, L., Groenendaal, H., and Zagmutt, F.J. (2017). "Outbreak-related disease burden associated with consumption of unpasteurized cow's milk and cheese, United States, 2009-2014." Emerging Infectious Diseases, 23(6), 957-964. https://doi.org/10.3201/eid2306.151603 (3.2% of Americans drink raw milk and 1.6% eat unpasteurized cheese; 96% of illnesses in dairy-linked outbreaks, 2009-2014); Centers for Disease Control and Prevention (2025). Raw milk (last reviewed 31 January 2025). https://www.cdc.gov/food-safety/foods/raw-milk.html; Centers for Disease Control and Prevention (n.d.). Preventing Listeria Infection. https://www.cdc.gov/listeria/prevention/index.html (higher risk in pregnancy, over 65 and with weakened immunity)
Note numbers are those of Chapter 6, The Gut That Expects Dirt.
This verdict is one of nine in the table Chapter 2 uses to show how the book judges a claim: find the primary study, and grade the claim by what it measured. The grade rates the evidence behind the verdict, by the book's stated method.
Educational content, not medical advice. Disclaimer.