Milk protein or casein intolerance occurs when the body has a food-specific IgG antibody response to the protein found in milk. This is not to be confused with lactose intolerance, which occurs wheninsufficient amounts of lactase are produced by cells in the small intestine.
If lactose is not broken down into smaller, simpler forms that can be absorbed into the bloodstream, a myriad of digestive symptoms may occur, including bloating, diarrhoea, cramps and flatulence.
IgG-mediated cow’s milk protein intolerance should also not be confused with an IgE mediated allergy, which is more common in those with an atopic or allergic disposition. IgE allergies cause a fast body reaction, often 2 hours or less after exposure. The easiest way to test for allergies is using a RAST test, commonly offered by your GP.
Why are we getting IgG-mediated food intolerances?
Because our guts are in such poor shape! 80% of our immune tissue is in our gut, the first point of exposure to potential pathogens. Having a good gut microbiome is crucial for protecting against toxins, microbes and allergens. Our gut barrier can become damaged by factors such as stress, excessive alcohol or pharmaceutical drug intake, chemicals, environmental pollution and cigarette smoking.
Our immune system then goes into overdrive and produces an inflammatory response. The gut barrier becomes damaged or leaky and that’s when antigenic (IgG-mediated) reactions to foods start to occur. Continuing to eat foods we are becoming intolerant to and reacting to only causes the problem to perpetuate.
How to identify a milk protein intolerance
Symptoms of food intolerance include :
- Digestive (IBS-type): abdominal pain, diarrhoea, bloating, constipation, nausea, stomach cramps.
- Dermatological: eczema, rashes, urticaria, psoriasis, acne.
- Neurological: migraine, headaches.
- Musculoskeletal: joint pain, fibromyalgia, swollen joints, rheumatoid arthritis.
- Psychological: anxiety, depression.
- Weight loss or weight gain.Often the reaction may be delayed by up to 72 hours and may affect any organ system. Intolerances may build up gradually.
How to test for a milk protein intolerance
There is a direct correlation between levels of food-specific IgG antibodies and markers of inflammation. This is why I recommend my clients do an IgG food intolerance test. IgG antibodies in the blood are very stable and show reactions to specific foods.
As a diagnostic for any condition, it can be used with nutritionist support as an aid to the management of dietary intake. It must be noted that foods to be tested should have been eaten within the last 3-6 months in order to get an accurate result.
Other ways to test include Vega testing and hair analysis but there is absolutely no scientific research to back either of these methods up so I would not recommend them.
The food intolerance test avoids the need for a lengthy exclusion diet (although it is still wise to avoid any foods that cause reactions without necessarily causing an antigenic reaction in any case).
The exclusion diet is viewed as the gold standard by the medical profession but it can be time consuming and compliance is often poor. In addition, it’s difficult to determine the exact combination of foods that may be causing symptoms, especially when the individual is under any form of stress, which has a huge impact on digestive function.
What to do if you are intolerant to cow’s milk protein
If casein comes up as something to avoid, all dairy, including goat and sheep milk products should be avoided for 3 months. Goat and sheep milk is naturally homogenised so often easier to digest but ultimately they have a similar protein to that of cow’s milk.
It’s important to record your symptoms in a food, mood and symptom diary so you can pinpoint reactions easily. Improvement is often seen within a month, but relief often comes quicker.
You should aim to be completely symptom-free for three months before reintroduction of intolerant foods. Reintroduction should happen gradually, starting with reintroducing one food once a week and building up to every other day. If symptoms return then food should be removed again for another month. It might be that you cannot tolerate cow’s milk and you need to avoid or take lactase if you eat or drink something containing it.
Look out for the following on ingredients labels and avoid:
- Casein and Caseinates
- Milk fat
- Sour cream