Milk allergy – fact or fiction?

A recent study that hit the news last week suggests that milk intolerance is ‘all in the mind’ – or at least mainly. Today (12/5/11) I’ll be discussing this, and the subject of food allergy and intolerance on the Vanessa Show on Channel 5 at 2.15pm.

The study, carried out by researchers at the University of Milan, tested over 100 people who complained of stomach pain, bloating and diarrhoea, believing that they were lactose intolerant. Lactose is the sugar in milk and many people, especially on Asian or African ancestry, don’t make enough lactase, the enzyme to digest it. The net result is digestive problems because bacteria in the gut feed off all that undigested milk sugar. The study hasn’t been published yet so it’s hard to know the details, but, according to newspaper reports about a third tested positive for lactose intolerance or malabsorption, leaving a majority that the researchers think have a psychosomatic aversion to milk. The problem with this is that it doesn’t appear that the authors have checked for milk allergy.

It is one thing to be lactose intolerance, which is an enzyme deficiency, but quite another to be milk allergic. An allergic is to the protein in milk (hence people often react more strongly to cheese, which has concentrated milk proteins) and involves the body producing antibodies. The two main families of antibodies are called IgE, which cause the fastest and most severe reactions, and IgG, which generally causes delayed reactions. While you can get digestive problems, such as Irritable Bowel Syndrome, as a result of such an antibody reaction, there are many other kinds of reactions associated with genuine milk allergy. These range from eczema, asthma, rhinitis, migraines and joint inflammation, leading to arthritis. These are all potential ‘inflammatory’ symptoms, resulting from the body’s immune system going into red alert. Since these apparently weren’t checked for in this study we don’t know how many of those not lactose intolerant might have a genuine IgE or IgG allergy.

Without that information is hard to know how much is potentially ‘psychological’ aversion. The best designed study to date on IBS symptoms and allergy is that of Drs Atkinson and Whorwell at the Department of Medicine, at the University Hospital of Manchester who devised an ingenious study, published in the journal Gut. They tested 150 IBS sufferers using Yorktest’s IgG based FoodScan test and then gave their doctors either the real results or fake results, and a supposedly ‘allergy-free’ diet to follow for the next three months judged equally challenging to follow. Neither the patients nor their doctors knew they were on a fake diet. At the end of the three month trial there was a significant improvement only in those people on their true food allergy-free diet. What’s more, those who stuck to it most strictly had the best results. Level of compliance, on the other hand, didn’t make a difference in those on the sham diets. The benefit achieved was substantially better than that expected by drugs in that one in two benefit, while conventional treatment benefits only one in 17.

Some articles wrongly dismiss IgG based allergies, saying that only IgE reactions cause really allergies. But, in the case of IBS, a study at St George’s Hospital in London found that there was no difference in the level of IgE reactions between IBS sufferers and controls, but a big difference in IgG antibodies. Those with IBS have a lot more IgE antibody reactions going on, suggesting an allergic mechanism for symptoms. In this study, the most common foods to produce IgG antibody reactons, both in those with IBS and the ‘healthy’ control subjects, was milk. This might suggest that milk is a hyper-allergenic food. As a case in point, I am IgE allergic to milk, proven by a proper blood test. I didn’t know this until I was 19. Throughout my childhood I suffered from migraines, frequent ear infections, rhinitis and sinus problems, ultimately resulting in three sinus operations. I had no digestive problems as such.

Once I eliminated milk the migraines virtually stopped and rhinitis considerably improved. However, when I speak to ENT specialists most dismiss the idea of milk allergy and few test properly with an IgE and IgG ‘ELISA’ blood test. Yorktest offers IgG testing, which requires a pin prick of blood, which can be taken using their home-test kit. I recommend them because they have a 98% reproducibility. Various labs can test for IgE, but since this requires a larger sample of blood this is best arranged through your doctor, nutritional therapist or health care practitioner. If you’d like to know more about this subject read my book Hidden Food Allergies