2017 Study: a2 Milk® is Easier on Digestion | a2 Milk® USA
2017 Study: a2 Milk® is Easier on Digestion | a2 Milk® USA

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2017 Study: a2 Milk® is Easier on Digestion

Posted on February 21, 2018

First, let me start with a disclosure: I am a science nerd. I love hypotheses, methods, and results. I read health and science journals for fun. So, when a new study on the effects of a2 Milk® was published, I spent hours digesting it (pun intended). If you’re a science nerd too, you can read the full-text study. Or read on for a summary.

The Study

The objective of this study was to support the notion that A1-protein free milk is easier on digestion than ordinary A1 and A2-protein milks. Currently, there are a handful of studies that show A1 protein free milk does not cause the digestive discomfort that some people experience when drinking ordinary milk. However, most of these studies involve a small number of test subjects. In this 2017 study, there were 600 participants.

The study was done using the gold standard of human research: a double-blind, randomized, cross-over study. These standards mean that neither the test subjects nor the researchers knew what kind of milk they were drinking.  The test subjects participated in both parts of the study: they drank ordinary cows’ milk (which contains both A1 and A2 proteins) and reported their GI symptoms; and they drank A1-protein free milk (in the form of a2 Milk®) and reported their GI symptoms.  

The Results 

After drinking a little more than 1 cup of milk, test subjects were asked to rate the severity of their digestive discomfort on a scale of 0-8 (0 = no symptoms; 8 = severe symptoms). The GI symptoms they recorded were: stomach grumbling, gas, bloating, abdominal pain, stool frequency, and stool consistency. They did this analysis for both kinds of milk.

Statistical analysis showed that all symptom scores were lower after subjects drank A1 protein free a2 Milk® when compared to their symptom scores after drinking the ordinary cows’ milk. This result indicates that a2 Milk® was easier on digestion in these subjects.

When considered in combination with earlier studies, this research implies that by drinking a2 Milk®, some people get relief from the digestive issues that ordinary cows’ milk causes.

What Does this Mean for You?

If drinking regular milk causes you digestive discomfort, try replacing it with a2 Milk®. If you haven’t been drinking milk for a while, add a little a2 Milk® to your meals gradually until you can drink a whole cup (for more ideas check out this blog).

Science nerd? Keep watching the a2 Milk® blog! There’s much more to uncover about the power and benefits of a2 Milk®.



Effects of cow’s milk beta-casein variants on symptoms of milk intolerance in Chinese adults: a multicenter, randomized controlled study. He, et al. Nutrition Journal (2017) 16:72.




Bonnie JohnsonAbout the Author

Bonnie Johnson, MS, RDN      Twitter_clear   @a2milkRD

Bonnie is a food-loving registered dietitian/nutritionist with a Master’s Degree in Nutrition Science & Education from Colorado State University.

Bonnie promotes the science and research behind a2 Milk® to Health Professionals and is on hand to answer simple health related questions from a2 Milk® consumers.

For more complex questions, please contact your favorite health care provider.


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