Food Allergies and Intolerances

It isn't un common that every now and then some of us will suffer some sort of digestive discomfort after eating. This can be infrequent, frustrating and some times scary. Any abnormal reaction after eating is called an adverse food reaction. This could be due to a food intolerance (sensitivity) or a food allergy. Today more and more people are suffering from some kind of food reaction, leading to them excluding certain food groups. So what is going on? Are people suffering from an allergy or an intolerance, and whats the difference? 

Food Allergies and Intolerances

An allergy is an immune reaction in which IgE antibodies are produced against a food or a specific substance in your environments (like Pollen). This triggers histamine release from the mast cells and basophils, which cause symptoms normally associated with allergies including, rashes, swelling, flushing or burning sensation in skin, abdominal pain, bloating, vomiting, diarrhoea, ear pain, sneezing, wheeling, itchy eyes, runny nose and increased heart rate. These symptoms can be dramatic (in the case of anaphylaxis) or subtle (in the case of mild seasonal allergies)

Common allergy/sensitivity foods are:
  • Pollen
  • Celery/celeriac
  • Cereal with gluten
  • Citrus
  • Dairy
  • Eggs
  • Fish
  • Mustard
  • Nuts
  • Peanuts
  • Sesame
  • Soya
  • Yeast

Food Allergy testing
Allergy testing can be done by blood or skin tests. Blood tests are fairly straight forward. The most common tests is called the RAST test which measures the presence of IgE antibodies in the blood. In skin tests, (considered more accurate) small amounts of allergens are placed on the skin of your arms or back. After a specific amount of time, the skin is evaluated for severity of reaction.

Food Intolerance
Food intolerances are immune responses other than IgE reactions. When you have a leaky gut, proteins from anything you eat can cross the gut barrier and interact with the immune system. The ongoing damage to your gut barrier, the more activated your immune system becomes, increasing your chances of food intolerances. While these foods don't normally irritate the gut or activate the immune system, because of the food intolerance, they now exacerbate inflammation. 

Elimination diets may be able to help figure out which foods you are sensitive to by eliminating suspects for 2-3 weeks and seeing if this makes a difference. If you suspect there are multiple culprits it may be worth doing an IgG food sensitivity test. In the case of leaky gut, I would advise that you work with a practitioner to determine which foods should be excluded for a period of time. Over time you should start to see improvements, and eventually start to reintroduce foods back int to your diet once your gut has healed and your immune system is better regulated. 
Unlike food allergies, intolerances tend to be transient. 


A food allergy
is an adverse response by your immune system and something that usually comes on suddenly. It can be triggered by a small amount of food. An allergy will happen every time you eat the 'certain' food regardless of how much you eat. Food allergies can be life threatening.

A food intolerance is not mediated by your immune system. It usually comes on gradually and can relate to the amount of food you have eaten. A food intolerance is not life threatening. Elimination diets can be beneficial to identity certain triggers.

If you have any questions please get in touch

Love H xx