Rethinking Dairy Sensitivity: The Fascinating Difference Between A1 vs. A2 Dairy

  • Dairy is an incredible source of nutrients (containing all three macronutrients: carbs, fat, and protein) that’s affordable and accessible for many families. However, in recent years, dairy is becoming a less popular choice, as it raises concerns for gut inflammation and digestive issues.
  • A1 and A2 refer to the types of protein found in different dairy products — and they can have a huge impact on how you digest milk, cheese, and yogurt. A2 dairy was consumed by our ancestors and even contains anti-inflammatory properties, while A1 milk could make inflammation worse for some.
  • A2 dairy products are easily accessible in the form of goat, sheep, and selective cow products (usually marked with an A2 label or purchased from a local farmer). These make for an easy switch for those who are sensitive to A1 dairy, but still want to keep the health (and taste) benefits of dairy.

Dairy isn’t exactly winning the popularity contest at your local coffee shop these days.

In fact, dairy is on the blacklist for many popular anti-inflammatory food plans and diets. If you’ve been pursuing holistic health for a while, maybe you, too, skip the coffee creamer in favor of a plant-based alternative that provides a similar taste and better digestion.

But what are you missing out on?

High-quality dairy offers ample (and easy) nutrition — like protein, amino acids, glutathione, and colostrum. It’s relatively inexpensive and can add a lot of variety and taste to your diet. And have we mentioned cheese?

What if there was a way to add dairy back into your diet without the uncomfortable bloating, acne, brain fog, and reduced energy?

Maybe there is!

Table of Contents:

A Breakthrough in Dairy Sensitivity: A1 vs. A2 Dairy

Did you know? Casein is the main protein found in dairy products (alongside whey). The different types of casein in dairy products could mean the difference between an emergency bathroom trip and absolute digestive bliss.

Sound too good to be true?

A2 beta-casein is a protein we find in ancestral dairy — the dairy of homestead farmlands, ancient civilizations, and indigenous populations. Humans have been exposed to this specific type of dairy (and protein) for thousands of years — with little issues.

But then A1 dairy entered the picture. Right as industrialized milk began to popularize, A1 beta-casein mutated its way into our diets via popular cow breeds.

Today, most westernized and industrial cows produce A1 dairy. Although the difference in the proteins is small (a single change in the 67th amino acid), consuming primarily A2 dairy can reduce inflammation and dairy-related digestive symptoms, making a big impact on how we feel.

Let’s dive in… 

Why Do Some People Tolerate A2 Dairy Better Than A1?

It all comes back to one word: Inflammation.

We know that inflammation in the gut can trigger (and irritate) all sorts of digestive issues. Leaky gut, IBS, Crohn’s disease, ulcerative colitis, and overall discomfort.

Well, one study suggests that A1 dairy may increase inflammatory markers by up to 260%.

Alternatively, A2 dairy is actually known to decrease inflammation in the body. 

So, if you experience uncomfortable digestive symptoms when consuming dairy, it might not be the dairy itself. It might be the type of dairy you’re consuming. 

Good news for cheese, yogurt, and ice cream lovers!

Histidine vs. Proline Amino Acids

As we know, proteins are made up of amino acids. It’s the sneaky amino acid in the 67th position that determines the difference between A1 and A2 protein. That’s just one tiny amino acid that could totally change your relationship with dairy products. 

  • The A2 amino acid (proline) is the original protein that’s existed for thousands of years. It’s the exact same kind of dairy our ancestors consumed — and is still popular today in indigenous populations and traditions, especially those that consume camel, sheep, and goat’s milk.
  • The A1 amino acid (histidine) is technically a mutation that occurred a few thousand years ago. So far, we only see it in cows — particularly western breeds of cattle. When digested, A1 dairy releases beta-casomorphin-7, a peptide that can be difficult to digest.
  • Milk with both A1 and A2 proteins is common, and many industrial cows produce both types of protein in their milk. However, each breed produces a higher level of one protein or the other. When you’re shopping for A2 milk, there may be a presence of some A1 protein, but not enough to impact your digestion.

Digestibility of A2 Dairy

Speaking of beta-casomorphin-7, let’s talk about it. Remember, this is the peptide released when we digest A1 dairy products only. Although studies are still being conducted, what we do know about this peptide is that it’s associated with higher inflammation levels, bloating, gas, and digestive discomfort. 

How big of a problem is A1 dairy, exactly? One study estimates that around 68% of people struggle with lactose sensitivity. Many researchers are testing to see if this sensitivity is actually related to beta-casomorphin-7 — instead of lactose — in some people.

Can Lactose Intolerant People Consume A2 Dairy Safely?

In short, no. People diagnosed with lactose intolerance shouldn’t consume either A1 or A2 dairy. The A2 amino acid, while healthier for some, doesn’t affect lactose levels.

However, there are a lot of people who assume they have lactose intolerance due to symptoms like bloating, gas, frequent bathroom trips, constipation, etc. They may joke about being “lactose intolerant” while eating an entire container of Ben and Jerry’s (we’ve all been there).

It’s possible that people with dairy sensitivity might be reacting to the A1 protein, not lactose! If you’re one of those people, it may be worth trying out A2 protein before cutting dairy products out of your diet entirely.

How to Prioritize A2 Dairy Products

So how do you know if you’re getting A1 or A2 dairy?

Most conventional dairy brands are produced by western cattle breeds (like Holsteins and Frisians), and these cattle produce A1 milk. 

A2 dairy is made by goats, buffalo, sheep, camels, and older cattle breeds (like Guernsey and Jersey). Breastmilk is technically A2 dairy as well. If you want to try A2 dairy, the best way is to buy cow’s milk from a local farm that uses Jersey cows or find a confirmed A2 source at your local grocery store.

Another way to try out A2 milk is to consume goat or sheep’s milk, easily accessible at a health food market and some grocery stores.

The Health Benefits of Dairy

Dairy can absolutely be part of a healthy diet — contrary to what clever marketing and Instagram influencers want us to believe. For many families, dairy is an easy and accessible form of calcium, phosphorus, vitamin D, potassium, and iodine. It’s also a “perfect” food with all three macronutrients: carbs, protein, and fat. 

The secret to consuming dairy in a healthy way is to find a way to eat it symptom-free. You can do this by… 

  • Consuming dairy with higher fat content. The fat in dairy is there for a reason and helps with the digestive process (by aiding in the absorption of vitamins and minerals present in the dairy). Full-fat dairy actually contains less lactose and it’s less likely to spike your glucose levels. Skim milk, for example, is primarily sugar when the fat is removed.
  • Consuming raw dairy. The pasteurization process can remove nutrients and digestive enzymes, causing sensitivity for some.
  • And of course, try A2 dairy products to lower inflammation and reduce digestive symptoms.

Exploring Raw Milk as an Option for Dairy Sensitivity

In some cases, raw milk may be the answer to your digestive distress. Both A1 and A2 dairy can be pasteurized or unpasteurized, which may affect the enzymes, nutrients, and other compounds present in the dairy. Some people can only tolerate raw milk (preferably, grass-fed), while some find processed dairy easier to handle. 

When it comes to consuming dairy, balance is important. Do some experimentation to find out how you tolerate dairy best and how you can easily incorporate it into your diet.

Small Lifestyle Habits Often Make the Biggest Impact on Our Overall Health

We have so many customers who thought their relationship with dairy was over for good. No more frothy coffee, no more ice cream movie nights, and lots of menu scanning when out to lunch with friends.

But small changes (like switching to A2 milk) have made all the difference in their experience — allowing them to once again consume a highly nutritious food group that they love (seriously, surviving without cheese? A nightmare).

We believe it’s small lifestyle changes — like switching to A2 dairy or raw dairy — that ultimately allow us to live full, happy lives, without extremes like cutting all dairy out of your life forever.

For many of our customers, Gut+ has been that small change. Created specifically to target chronic gut symptoms and create a flourishing microbiome, Gut + is the one essential supplement our customers are turning to for better digestion and all-around energy.

Change Your Digestion for Good with Just One Daily Pill — Try Gut +


Sodhi, M., Mukesh, M., Kataria, R. S., Mishra, B. P., & Joshii, B. K. (2012). Milk proteins and human health: A1/A2 milk hypothesis. Indian journal of endocrinology and metabolism, 16(5), 856.

Jianqin, S., Leiming, X., Lu, X., Yelland, G. W., Ni, J., & Clarke, A. J. (2016). Effects of milk containing only A2 beta casein versus milk containing both A1 and A2 beta casein proteins on gastrointestinal physiology, symptoms of discomfort, and cognitive behavior of people with self-reported intolerance to traditional cows' milk. Nutrition journal, 15, 35.

Ul Haq, M. R., Kapila, R., Sharma, R., Saliganti, V., & Kapila, S. (2014). Comparative evaluation of cow β-casein variants (A1/A2) consumption on Th2-mediated inflammatory response in mouse gut. European journal of nutrition, 53(4), 1039–1049.

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