Allergy to Food Additives and Preservatives

Allergies Clinics of London

Adverse Reactions to Food Additives.

Food Additive Reactions are usually due to an Intolerance to artificial and natural chemicals found in packaged, processed and Take-away Foods.

Preservatives (to give food a longer shelf-life)

The Sulphites.

These chemicals in the form of gases cause lung irritation and may trigger asthma. They are commonly found in liquid form in cold drinks and fruit juice concentrates, but also in wine and sprayed onto foods to keep them fresh and prevent discoloration or browning. They are used to preserve smoked and coldmeats, dried fruit and salads. In the solid form, sulphites can cause urticaria when ingested.

Sulphur dioxide, Sodium sulphite, Sodium bisulphite, Potassium bisulphite and Potassium metasulphite.

Benzoic acid and Parabens.

Benzoates and Parabens have antibacterial and anti fungal properties for prevention of food spoilage. These agents are added to pharmaceutical and food products and occur naturally in prunes, cinnamon, tea and berries. They may cause urticaria, asthma and angioedema.

Sodium benzoate, Methylparaben, Propylparaben and Heptylparaben.

Antioxidants:

Fat and oils in food turn rancid when exposed to air. Synthetic phenolic antioxidants (BHA and BHT) prevent this happening but can trigger asthma, rhinitis and urticaria.

Butylated hydroxyanisole (BHA) and Butylated hydroxytoluene (BHT)).

Flavourings (to enhance food palatability).

Aspartame: a low calorie sweetener can trigger urticaria (nettle rash), itchy hives and swelling of the body.

Monosodium Glutamate (MSG) which can trigger the "Chinese Restaurant Syndrome" of burning and tightness in the chest, neck and face.

Colourings (make food visually more attractive).

Azo dyes (Tartrazine) and Non-azo dyes (erythrocine).

All colourings must now be labeled. They can trigger hives, urticaria, asthma and generalized allergic reactions.

Nitrates and Nitrites - give meat a pink colour to look more attractive and found in bacon, salami and frankfurters ( E 249 - E 252 )

Emulsifiers and stabilisers

Stop oil and water components separating, as in ketchup and mayonnaise, but do not cause adverse reactions.

Naturally occurring substances in food causing adverse reactions.

Vaso-active amines.

Natural Histamine, Serotonin and Tyramine occur in some ripe cheeses, fish, cured sausage, red wine, chocolate and pickled vegetables and can induce cramping, flushing, headache and palpitations in a dose related manner.

Caffeine found in foods, medication, tea, coffee and Coca-Cola induces dose dependent agitation, palpitations, nausea and tremors.

Salicylates (aspirin-like naturally occurring chemicals).

Salicylates induce urticaria, asthma and nasal polyps to develop. They are found in Curry powder, paprika, dried thyme, oranges, apricots, ginger, honey, berries and fruit skins, tea and almonds. Salicylate sensitive individuals also tend to have adverse reactions to benzoates and tartrazine.

Always read all packaged food labels, legislation now ensures that additives must be clearly labeled. E Numbers – all additives used within the European Community must have an E number.

Colourings: (E100-180) Tartrazine E102, Sunset YellowE110

Flavourings: (E620-635) Monosodium Glutamate E620

Preservatives: (E200-297) Benzoates (E210-219), Sulphites (E220-227),

Nitrates (E249-252).

Antioxidants: (E320-321) BHA (E320) & BHT (E321)

General rules for preservatives and additives:

No accurate diagnostic tests are yet available - so be suspicious of any advertised in the media.

Relatively few adverse reactions are actually reported when compared to nuts, eggs and other foodstuffs.

Read food labels carefully, keep food diary's to identify offending additives and preservatives.

Melkersson-Rosenthal Syndrome is a rare disorder possibly triggered by sodium benzoate and characterised by lips granulomas, facial paralysis and fissured tongue. It tends to occur in atopic individuals.

Written by Dr Adrian Morris Click here for the Surrey Allergy Clinic.

September 2006.

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