Dairy Intolerance

Dairy Intolerance - Symptoms and causes

Welcome to our dairy intolerance FAQ. Here at the intolerance lab, we deal with intolerances, not allergy, and so today we are specifically delving into what a dairy intolerance is and how it’s different to lactose intolerance. If you think you might have lactose intolerance you can refer back to our article on lactose intolerance to read much more about that.

Dairy intolerance is an immune response to the proteins found in dairy, most commonly to the casein protein. The immune system can generate IgG and IgA antibodies in response to consuming dairy, and these cause inflammatory reactions throughout the body. We discuss casein and why It’s important to understand its role in dairy intolerance, what the main symptoms of dairy intolerance are, how it differs from lactose intolerance, how you can get a diagnosis and then we delve into what you can and can’t eat and the ways in which you can manage a dairy intolerance.

To be clear, this FAQ is specifically discussing casein intolerance. Let’s start with learning about what a dairy/casein intolerance is:


What is a dairy intolerance?

Dairy intolerance, also called dairy sensitivity, is an inflammatory immune reaction to the proteins found in dairy. Often people are reacting to casein, which is a major protein found in dairy. The other main protein in cow’s milk dairy is called whey.
Where casein is the issue, things can get confusing, but stick with us. This is because there are different types of casein, with beta-casein being one that we know a lot about. The first type of beta-casein is known as A1, and it is linked to many symptoms and issues. The second type of beta-casein is called A2 and appears to have a lot fewer reactions and sensitivities associated with it. Generally speaking, A2 casein is well tolerated by the general population, which is why you see A2 milk available in supermarkets today.

Why is casein important?

Casein is important to understand because of the issues it can cause, and also because it is the most prevalent protein in cow’s milk. Overall, the protein in cow’s milk is roughly 80% casein and 20% whey, which accounts for why people have more issues with casein. In comparison, human breast milk has only 40% casein.

The A1 type of casein from cow’s milk has been linked to many conditions and symptoms that arise from ingesting it. They include but aren’t limited to:

  • ADHD and autism spectrum disorders
  • Asthma and other breathing difficulties, it increases mucus production
  • Heart disease and plaque build-up in the cardiovascular system
  • Sleep apnoea
  • SIDS – sudden infant death syndrome
  • The development of Type 2 diabetes


And many more.

It is believed that these reactions occur because of the way that A1 casein is digested. Upon digestion, it releases an opiate-like substance called beta-casomorphin-7, which activates various receptors in the digestive tract. This has been shown to affect stool consistency and abdominal pain, as well as raise histamine levels. Histamine causes inflammatory processesin the body. The same effects did not occur with A2 casein, however, more study needs to be done in this area to reach conclusive answers.

There is also some immune involvement with casein sensitivity, and there may be some IgA or IgG antibodies produced in response to ingesting it. This is different from allergy responses, as they generate IgE antibodies that are responsible for severe and life-threateninganaphylactic reactions. Both responses do however cause inflammation and discomfort, but intolerances are NOT life-threatening.

What are the symptoms of dairy/casein intolerance?

Casein is quite slow-digesting, which means that it can take days for the symptoms to arise. They can also be varied, so it can be difficult to pinpoint a dairy intolerance that isn’t lactose related. The main symptoms include:

  • Bloating and stomach cramps
  • Diarrhea or constipation
  • Gas, lots of gas
  • Nasal congestion, stuffy nose
  • Skin rashes, especially eczema and adult acne
  • Behavioural issues in children
  • Fatigue, exhaustion and lethargy
  • Joint pain
  • Foggy brain
There can be other symptoms that appear random or unrelated, but this is a very individual thing as everybody literally reacts differently.

How does lactose intolerance differ from a dairy intolerance?

It’s very easy for people to confuse the two and think that they are one and the same. However, lactose intolerance is caused by a deficiency in the enzyme lactase. This enzyme digests lactose within the digestive tract, and if it isn’t present than people exhibit the symptoms of lactose intolerance. These symptoms are most commonly:

  • Bloating
  • Diarrhea
  • Gas and stomach pains
  • Nausea

Dairy intolerance is an inflammatory response to protein components in dairy itself and has nothing to do with lactose, which is a sugar found in dairy products. The symptoms can also be quite different and include things like joint pain, behavioural issues and brain fog as listed above.

How do I get a diagnosis of dairy/casein intolerance?

There are several ways to find out if you have an issue with the casein proteins in dairy.

The most common way is to have a food intolerance blood test done. This type of test uses your blood sample to test for IgG or IgA reactions against food proteins, which signifies that you have an intolerance. You need to make sure that the test you do has casein as one of the foods that are tested, otherwise, it won’t show up.

There are also IgE tests, but these are for allergic responses, not intolerances.

Doing a food challenge is also a viable way to assess if you have any type of intolerance. Remove the food for 30 days, in this case dairy, and then consume some after the 30 days. Wait and watch for reactions. This can be time consuming and inconclusive, but if done well it can give you some good answers.

Our intolerance lab hair test is the most non-invasive way to find out if you have casein intolerance. We use a few strands of your hair and run them through our biofeedback machines to assess you for any food intolerances present, including casein and 700 other items as well.

What are the risk factors for developing dairy intolerance?

Like all food intolerances, the health of your gut and digestive system has a big part to play. If you have leaky gut then you are predisposed to developing food intolerances, including dairy and casein intolerances. When this occurs, proteins from the foods you consume, in this case casein, get through into your bloodstream and cause inflammatory reactions.

Irritable bowel syndrome is also a risk factor for developing dairy intolerances because the gut is already inflamed and damaged.

Gluten intolerance is also a risk factor, as there is a high percentage of people with both gluten and dairy intolerance concurrently.

In infants, having atopic eczema and being bottle-fed with cow’s milk formula are also risk factors in developing dairy intolerances. In fact, casein intolerance is most commonly seen in infants and children under 5 years old.

Having relatives with a dairy/casein intolerance is also believed to be a risk factor for developing the condition.

Foods to avoid if you have dairy/casein sensitivity.

Casein is one of the proteins in dairy, so it is found in higher quantities in high protein dairy foods. These are the high protein dairy foods you need to avoid:

Cow’s milk – all types

Cow’s milk yogurts – all types

Diary custards and desserts that are pre-made

Cow’s milk cheeses – all types

Kefir fermented milk

Butter, butter spreads and cream have much less protein than the above dairy foods. They have trace levels of casein only, and so some people with a casein intolerance may be able to tolerate a bit of butter and or cream. This is something that you need to assess for yourself and watch for your bodies reactions too.

If you are highly sensitive to casein then it’s recommended that you don’t have butter or cream either.


Dairy-free: what you can eat

In regards to dairy, if you have a casein sensitivity it is best to avoid all types of cow’s milk dairy products as mentioned above.

However, you can try A2 milk to see if you react the same way to this. If your body tolerates it much better, then this would be a good option for you. However if you do react to it, then please avoid A2 milk as well.

Ghee is also an option as it contains no casein due to the way it is processed. Try it and see if you can tolerate it.

Are there any cures for dairy intolerance?

The answer to this is unfortunately no. The main thing that you can do to prevent dairy intolerance symptoms is to avoid all sources of high protein/casein dairy food in your diet. These are listed above for you to see.

What is the best treatment for dairy intolerance?

Really the only treatment available is to remove dairy from your diet.

However, if your dairy intolerance is caused by another issue such as leaky gut or irritable bowel, then seeking treatment to heal the underlying condition may also alleviate the dairy intolerance.

Naturopaths and Holistic Nutritionists are your go-to for healing your digestive tract.

How long do the symptoms of dairy intolerance last for?

If you have a casein intolerance, the symptoms may not show up for a few days. This is because the casein itself takes a long time for the body to digest. You may exhibit symptoms from 3 to 5 days after consumption of dairy, but they shouldn’t last any longer than that; providing you haven’t eaten any more dairy products.

Can a person intolerant to dairy eat ghee?

This is an individual assessment, as everyone reacts differently. Ghee is clarified butter, with the milk solids and water portion removed. Both lactose and casein are removed through this process, and so ghee is essentially lactose and casein free. However some people may still react to it, so our recommendation is to try a small amount of it for yourself and see if you can tolerate it or not.

Is it possible to have an intolerance to milk fat?

Generally no. The fat levels in milk have not been proven to affect the symptoms of casein intolerance or lactose intolerance.

You can however have a poor ability to digest fats, and this would include milk fats. If this is you, anytime you have a portion of food containing high amounts of fat you may get digestive symptoms such as nausea and stomach pains, as well as fatty stools that float.

You can rectify this with the help of a Naturopath, who will use herbal medicine and dietary means to help your body digest fats more efficiently.

Why does milk give me brain fog and stomach pains?

This reaction occurs when you are intolerant to the proteins in cow’s milk, in this case the casein protein. When you ingest it, you have an inflammatory reaction that causes the symptoms of brain fog, stomach pains etc.

Why am I suddenly allergic to dairy?

Food intolerances can seem to suddenly appear out of nowhere. However what’s usually happening is that your digestive tract has some kind of issue, such as leaky gut or irritable bowel etc. This, in turn, creates a permeable gut lining, so the proteins in the food you eat can then escape through the gut lining into your bloodstream. The proteins cause an inflammatory response in your body, and this is when you have symptoms and reactionsand it seems like they just happened overnight. In reality, it is a long-term situation, and you can rectify it by healing your digestive tract with a Holistic Healthcare Practitioner.

Is dairy bad for the digestive system?

This depends on the health of your digestive tract, and whether or not you have dairy intolerances.

Dairy itself is a highly nutritious food with many benefits, however, if you do have an intolerance to it then it will cause you digestive upsets and other symptoms as detailed above. If you are intolerant to it, then yes it is bad for your digestive system. If you are not intolerant to it, then it is worth keeping in your diet for the nutritional benefits it gives.


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