- Carina Harkin, BHSc.Nat, BHSc.Hom, BHSc.Acu

Food allergy
Food allergy involves the abnormal reaction of a persons immune system to a food substance, much in the same way that a person can be allergic to pollen.

Symptoms of food allergy
Common symptoms include hives, eczema, asthma, hayfever and Attention Deficit Hyperactivity Disorder (ADHD). A good one in regard to children is dark circles under the eyes. These are known as allergic shiners. Food allergy can be either obvious or difficult to recognise.

Immediate food allergy
Some people have an obvious allergic reaction to food. This is called anaphylaxis. Anaphylaxis is a sudden, potentially fatal, allergic reaction that can involve the skin, respiratory tract, gastrointestinal tract, and cardiovascular system.

Anaphylaxis is mediated by IgE antibodies, interacting with mast cells. The mast cells are present in the membranes lining the nose, respiratory tract, eyes and intestine. A substance known as histamine and other inflammatory mediators present in mast cells are released, causing symptoms such as a runny nose, dilation of blood vessels and flushing, swelling and difficulty breathing.

Peanuts are well known for causing this type of extreme reaction. Other foods that are known to cause a severe reaction are tree nuts, seeds, eggs, milk and shellfish.

Delayed food allergy
Some food allergy symptoms occur long after eating the suspect food. These reactions are called delayed food allergy and are mediated by immune complexes (antigen-antibody complexes), which continue to circulate in the bloodstream. These circulating antigen-antibody complexes can lodge in tissues creating problems such as asthma, eczema and hayfever, but can also be indicated in severe autoimmune disorders such as rheumatoid arthritis and insulin dependant diabetes.

Delayed reactions to food may take hours or days to develop. Foods causing reactions of these types include cows milk, eggs, fish, wheat, yeast, soya, pork, chocolate and citrus fruits. Yes, soya is a highly allergic food.

Why do delayed reactions occur?
Ideally, food should be broken down into single protein molecules and pass through the gut wall to be used by the body. Sometimes, due to insufficient digestive enzymes, proper digestion does not occur. These undigested, protein molecules can tear a hole in our gut lining and get into the bloodstream. This is known as Leaky gut syndrome. The body sees these undigested food particles as foreign invaders and creates antibodies against these foreign antigens. These circulating immune complexes can lodge in body tissues, such as the lungs, causing asthma, or the joints, causing rheumatoid arthritis.

Testing for food allergy
Confirmation of the existence of an allergy can be made through an exclusion or low reactive diet. The idea is to place the person on a restrictive diet for 2 weeks then test suspect foods. After the body has had a break from the food allergen, it will produce stronger symptoms that are easily recognisable. There are other biologic tests that can be requested for food allergy also.

Naturally occurring substances to reduce

Histamine containing or releasing foods
Substances known as vasoactive amines, which include histamine and tyramine, are found in cheese, chocolate, wine, pickled foods and citrus fruits, particularly oranges. Orange juice is the worst thing to have when you have a cold! Some foods have a histamine releasing action such as egg whites, shellfish, strawberries, tomatoes and chocolate. Excessive amounts can exacerbate allergies and headaches in particular.

Salicylates
Salicylates are aspirin-like naturally occurring chemicals. We know that asthmatics can be sensitive to aspirin but are we aware that certain foods contain salicylates? They are particularly high in all spices such as Curry powder, paprika and thyme, oranges, apricots, honey, tea and almonds.

Preservatives – Sulphites and Benzoates
These chemicals may trigger asthma and hives. They are commonly found in soft drinks, fruit juice, wine (sorry), smoked meats and dried fruit. (E220 – E227). Benzoates are antibacterial and anti fungal preservatives. They may cause hives and asthma. These occur naturally in prunes, cinnamon, tea and berries however, are also added to foods. Benzoyl peroxide is used as a bleaching agent in the manufacture of white flour. (E 210 – E 219)

Flavourings – aspartame and monosodium glutamate (MSG)
Aspartame is low calorie sweetener can trigger urticaria (nettle rash) and hives. MSG can trigger the “Chinese Restaurant Syndrome” of headache and burning, plus tightness in the chest, neck and face. (MSG is E 620 – E 635)

Colourings – Tartrazine and Nitrates
Tartrazine is a yellow food colouring that can trigger hives, urticaria and asthma. (E 100 – E 180). Nitrates give meat a pink colour and are found in bacon, salami and ham (E 249 – E 252). Nitrates may cause dizziness, headaches, difficulty breathing, and are potentially cancer causing.

Dietary advice
Rotate cows milk yoghurt (it is lactase free), soy milk, rice milk, goat milk and oat milk. Buy goat or sheep milk cheese from the Galway market. Most feta in the supermarket is cows milk, some is goats, you must check.

Wheat, rye, barley and oats contain gluten. Good alternatives are millet, polenta, rice, buckwheat and quinoa. All these can be used instead of pasta. There are gluten free flours such as soy flour, potato flour and chickpea flour or besan flour. Spelt bread is a good, wheat free alternative or try rice crackers or oat cakes. There are many pasta alternatives such as rice noodles, corn noodles, buckwheat noodles or gnocchi.

Decrease red meat consumption as this is high in arachidonic acid which is pro- inflammatory. Increase consumption of anti-inflammatory foods such as oily fish, fruits and vegetables rich in vitamin C and bioflavanoids such as blueberries, cherries and peppers. Fresh turmeric and ginger are strong anti-inflammatories.

Avoid preservatives, flavourings and colourings and foods high in salicylates and vasoactive amines. Rip out this page and take it shopping! The message is simple. When it comes to allergies, if you love them dont feed them junk.

Beneficial supplements

Glutamine
Glutamine is an amino acid strongly implicated in gut repair to prevent leaky gut.

Probiotics
There is loads of quality evidence to suggest that healthy bowel flora decrease risk of atopic disease such as asthma, eczema and hayfever.

Digestive enzymes
There are lots of enzymes needed to break down various foods in your stomach, and a supplement can help if your digestion is impaired.

Quercetin and Vitamin C
Both are natural anti-histamines. Quercetin is a bioflavanoid found in large amounts in apples and red onion. It strongly anti-histamine.

Methione
Methione is involved in the breakdown of histamine.