I’m a Public Health Scientist. Here’s What Research Really Shows About Raw Milk.

Do a quick search for ‘raw milk and lactose intolerance’ on social media, and you’ll find thousands of posts claiming unpasteurized milk is the answer for those who can’t digest dairy. As a public health data scientist specializing in evaluation science and critical appraisal of evidence, I’ve noticed these claims spreading rapidly — especially claims about raw milk’s supposed ability to cure lactose intolerance. Through my work with Unbiased Science, where we focus on sharing evidence-based information, I’ve examined the research on this topic carefully. And when we look at the actual studies, including a groundbreaking Stanford trial, the evidence reveals something very different.

The Claims vs. The Science

Raw milk proponents make two main arguments regarding lactose intolerance: first, that raw milk contains natural lactase enzyme to help digest lactose, and second, that its naturally occurring bacteria aids lactose digestion. These claims sound reasonable on the surface — but what does the research actually show?

A 2014 Stanford randomized controlled trial (RCT) put these theories to the test, comparing raw versus pasteurized milk in people with confirmed lactose intolerance. The results were striking: raw milk actually performed worse than or equal to pasteurized milk in terms of lactose digestion.

Understanding the Evidence

The Stanford researchers used breath hydrogen levels — a scientific measure where higher numbers indicate worse lactose digestion — to track how well participants processed different types of milk. Initially, raw milk showed significantly worse digestion (113±21 vs 71±12 ppm·min), about 60% higher than pasteurized milk. By day eight of the study, both types of milk performed equally (72±14 vs 74±15 ppm·min), with participants reporting identical digestive symptoms.

This research definitively demonstrated that raw milk offers no advantage for lactose-intolerant individuals. Laboratory analysis has repeatedly confirmed there is no lactase enzyme present in any milk, raw or pasteurized, and both types contain identical amounts of lactose (4.8%).

Why Yogurt Helps (But Raw Milk Doesn’t)

Many people wonder why fermented dairy products like yogurt can help with lactose intolerance while raw milk doesn’t. The answer lies in the specific bacteria and their concentrations. Yogurt contains deliberately added beneficial bacteria (Streptococcus thermophilus and Lactobacillus bulgaricus) at concentrations of 107 CFU/ml or higher — levels proven to aid lactose digestion.

In contrast, raw milk’s natural bacteria are different species present in much lower numbers, making them clinically insignificant for lactose digestion.

The Hidden Dangers

While the lack of benefits is concerning enough, the risks of raw milk consumption are severe. Between 1998–2018, despite only 5% of Americans consuming raw milk products, they caused:

202 disease outbreaks

2,645 illnesses

228 hospitalizations

Three deaths

Children face particularly high risks. Multiple documented outbreaks show devastating consequences:

In 2005, all five hospitalized patients in an E. coli outbreak were children aged 1–13

In 2006, six children developed severe kidney complications due to raw milk

In 2008, the three most seriously ill patients in a 14-person outbreak were children

A Surprising Discovery About Lactose Intolerance

The Stanford study revealed another fascinating finding: of 63 people who believed they were lactose intolerant, only 27 (43%) tested positive for lactose malabsorption when scientifically tested. This suggests that many perceived benefits of raw milk may stem from misunderstanding the underlying condition.

Evidence-Based Solutions for Lactose Intolerance

For those truly struggling with lactose intolerance, research supports several safe and effective approaches:

Using lactase enzyme supplements

Consuming lactose-reduced dairy products

Choosing properly fermented products like yogurt

These methods have been proven effective through rigorous clinical testing, unlike raw milk consumption which carries significant risks without documented benefits.

Moving Forward

The appeal of “natural” solutions is understandable, but when it comes to milk, pasteurization remains one of public health’s greatest success stories. Before its widespread adoption in the 1920s, contaminated “swill milk” caused thousands of infant deaths. Today, pasteurization continues to protect us while preserving milk’s nutritional benefits.

As we navigate health choices in an age of abundant information, we must rely on scientific evidence rather than anecdotal claims. The data is clear: raw milk provides no benefits for lactose intolerance while posing serious health risks, particularly to children.

Note: While this article synthesizes current research findings, always consult with your healthcare provider about managing lactose intolerance or making significant dietary changes.