Milk Allergy, Milk Intolerance or Lactose Intolerance?

The terminology used for allergies and intolerances is frequently applied in an interchangeable manner. The terms milk allergy, milk intolerance and lactose intolerance are often thought of as one in the same. However, in fact, they are three different conditions with different physiological processes and subsequently require specific testing methods. Whilst a milk allergy and a milk intolerance are immune-mediated requiring blood allergy testing or intolerance testing, lactose intolerance is enzyme-mediated meaning symptoms occur due to an insufficiency of the enzyme lactase and in this case, a breath test is required.

In milk allergy testing and milk intolerance testing, your blood is tested for antibodies, IgE and IgG respectively, which your body creates against the proteins in the milk. Lactose intolerance is an inability to break down the sugar element, lactose, in the milk due to an insufficiency of the enzyme lactase. The inability to break down and absorb the lactose results in the production of gases, hydrogen and methane. These are exhaled and levels can be tested to identify the condition.

Whilst all three conditions can result in symptoms which can be debilitating such as bloating, stomach cramps, vomiting and diarrhoea, it is a milk allergy, which has the potential to be life-threatening. For most people allergies result in symptoms such as coughing, sneezing, runny nose, swelling of the lips/mouth, itchy lips/mouth or vomiting, but for some, they can be as severe as an anaphylactic shock which can be fatal. If you suspect you or a family member has an allergy to milk then allergy testing is highly recommended, particularly if you, or they, also have asthma.

The dietary implications of these conditions depend upon which one you have. With a milk allergy, it is recommended that you eliminate all milk products from your diet on an on-going basis. In the case of milk intolerance, your results may indicate that you are intolerant to certain milk products but not others, for example, milk but not cheddar cheese. This is due to the differing levels of proteins and bacteria in the various milk products. An initial period of elimination of 4 weeks is recommended, following this you may be able to successfully reintroduce the items however this is highly individual and many people choose to continue abstinence or reduce their intake of the intolerant milk products as they feel better for it. With lactose intolerance it is not always necessary to remove all milk products, this is because certain milk products, such as aged hard cheese, butter or probiotic-rich plain yoghurt have very little lactose in them, but this depends upon the severity of your lactose intolerance.

So to summarise the crucial differences in these conditions; milk allergy and milk intolerance are immune-mediated, meaning they produce antibodies against proteins in the food and can, therefore, be tested using IgE antibody allergy testing or IgG intolerance testing. Lactose intolerance is an insufficiency of the enzyme lactase resulting in the inability to break down the milk's sugar and can be tested for using a breath test.

If you suspect your symptoms relate to a milk allergy or milk intolerance click here to see our range of Lifelab testing kits.