Don’t Tolerate Dairy? Here’s What to Do

Do you consume lactose-free dairy in an attempt to improve digestive symptoms, only to find that your symptoms don’t actually get any better? If so, you’re not alone.

Many times, patients who struggle to digest lactose-free dairy don’t have a problem with lactose, but rather, a type of protein found in dairy called A1 protein. Good news – you might not need to cut out dairy at all! Let’s dive into the different reasons why dairy might cause digestive distress, and what to do about it.

What is lactose intolerance?

You might be surprised to learn that there are multiple reasons that a person might not tolerate dairy products. The first of these is lactose intolerance. Lactose is a type of natural sugar found in milk and dairy products. It is normally broken down by the enzyme lactase. Some people do not produce enough of the lactase enzyme, meaning lactose can move through the gut undigested. When lactose reaches the colon, it gets fermented by our gut microbiome, causing symptoms like gas, abdominal pain, bloating, and diarrhea.


To manage lactose intolerance, people can either choose lactose-free dairy products or take lactase enzyme pills to help them digest lactose.


But what if you still get digestive symptoms when you’re eating lactose-free dairy products? This could be a sign that it’s the A1 protein found in dairy that’s causing your digestive distress.


Difficulty digesting A1 Protein?

Milk contains both whey and casein proteins. About 30% of the protein in cows’ milk is a type of protein called beta-casein. In Canada, most of our milk found on the shelves is a mix of A1 and A2 beta-casein.


Research shows that when A1 protein is digested, it breaks down in a way that can cause digestive symptoms similar to those caused by lactose intolerance including gas, abdominal pain, bloating, and diarrhea. In fact, a study compared the impact of A1 versus A2 protein on digestion and found that A1-containing milk was associated with significant increases in digestive symptoms. When the group went on to consume milk containing only A2 protein, it didn’t cause the same digestive symptoms, showing how this tiny difference can make a big impact on a person’s symptoms1.


Luckily, a2 Milk™ comes from cows that only produce A2 protein. If you struggle to digest A1 protein, you can still enjoy milk! Many people who try a2 Milk™ say they can feel the digestive difference and avoid digestive discomfort.


Is there a test for dairy intolerance?

So, how will you know if you’re lactose intolerant or that you struggle to digest A1 protein? There are several tests to measure lactose intolerance. The most common are breath tests or blood tests, where you consume a lactose-containing beverage, and over a period of time, the lab is able to measure whether or not you’ve digested the lactose.


Unfortunately, there is no validated test to determine whether a person will struggle to digest A1 protein. However, that doesn’t mean that we can’t use a little experimentation (also known as empiric testing) to figure out whether an A1 protein intolerance is why you don’t tolerate dairy!


Is there a way to see if my tummy troubles are caused by A1 protein?

To test whether you struggle with A1 protein, you’ll need to put on your ‘scientist’s cap’ and be prepared to do a little self-experimentation. This simple step-by-step method is what I use with patients when exploring whether A1 protein might contribute to their digestive symptoms.


First, I start with a temporary trial of lactose-free dairy products (like lactose-free milk). If their symptoms resolve, it’s likely that lactose is the culprit. However, a handful of my patients report that even with lactose-free dairy, they still experience symptoms.


If that’s the case, we do a temporary trial removing all dairy from the diet. This includes temporarily removing things like milk, yogurt, and cheese. If symptoms improve, this tells me dairy could be contributing.


Our next step is to add milk back in. We start with a2 Milk™to determine whether it could be the A1 protein contributing to symptoms. Since most milk on the shelves at the grocery store is a mix of A1 and A2 protein, you’ll want to choose a2 Milk™ – which only contains A2 proteins.


If we know the patient is lactose intolerant, I’ll have them take their lactase enzymes to ensure lactose intolerance doesn’t confound the results. If my patients are unsure of whether their lactose intolerant or not, I often have them utilize lactase enzymes to ensure there are no confounding variables interfering with the results of their trial.


If my patient tolerates a2 Milk™ – that is a pretty good indicator that it could be A1 protein causing their digestive distress – but we do one final check to see. Once they’ve trialled a2 Milk™for at least a few days and symptoms remain improved, it’s time to trial regular milk. For the best comparison, trial an equal amount of regular milk to a2 Milk™. For example, if you trialled two cups of a2 Milk™ daily, consume two cups of regular milk daily.


Finally, compare your digestive symptoms between when you were consuming lactose-free dairy products, regular milk products, and a2 Milk™ If your digestive symptoms improved when you were consuming the a2 Milk™, A1 protein could be the culprit of your digestive distress. The good news is that a2 Milk™ is a great way to consume dairy without worrying about digestive symptoms. No reason to give up dairy, simple swap your regular milk fora2 Milk™ to feel the digestive difference.


The takeaway

For people experiencing digestive symptoms with dairy products, often the first conclusion they jump to is that they’re lactose intolerant. If symptoms persist, they assume they can’t tolerate dairy at all and often give it up. However, symptoms could be caused by the A1 protein found in most of our milk available on the shelf. By following a simple step-by-step trial, you can tease out whether you might be intolerant to A1 protein. Research has shown that A2 protein is naturally easier on digestion. a2 Milk™ is sourced from cows that naturally produce only the A2 protein, making it a delicious way to incorporate dairy back into your diet, without experiencing digestive discomfort.

1.     Ho, S., Woodford, K., Kukuljan, S., & Pal, S. (2014). Comparative effects of A1 versus A2 beta-casein on gastrointestinal measures: a blinded randomised cross-over pilot study. European journal of clinical nutrition, 68(9), 994-1000.

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