The sulphites are chemical compounds, acid salts based on sulfur, more specifically the sulfite ion S03 2-. Thanks to their antibacterial and antioxidant action, manufacturers use them as preservatives in many foods and drinks.

In some people, a intolerance to these sulfites can develop, which will lead to an allergic-type reaction. However, sulfite intolerance should be distinguished from allergy, because unlike the latter it has no impact on the patient’s immune system. It is thus similar to theLactose intolerance, which also has digestive problems.

Note that people already suffering from other allergies are more likely to be intolerant to sulfites, especially those allergic toaspirine or mites.

It is possible to find traces of sulphites in many foods in which they have been added as preservatives, or sometimes naturally, such as in wines. This means that they help preserve the food in order to delay its decomposition, and therefore make it edible longer. 

Here is a list of foods that contain sulphites, but many more exist and it will be necessary to watch the labels of the packages to make sure:

• Wines and champagnes: there are sulphites in many wines, the very process of winemaking requiring a little sulphites, to which sulphites are added as preservatives (and this since ancient Roman times). It is above all white and rosé wines that contain it in quantity, red wine having less in comparison.
• Beers;
• Cider and chouchen;
• Potatoes ;
•  Raisins ;
•  Frozen fish and seafood;
•  Dried fruits (especially apricots) ;
• Mustard;
• Vacuum-packed and preserved vegetables;
• Canned pickles;
• Cold cuts;
•  Cereal bars ;
• Olives ;
• Muesli ;
• Frozen or prepared meals;
• Syrups (based on glucose or dextrose) ;
• Vinegars;
• Pasta (only some brands) ;
• Medications.

Intolerance to sulfites will trigger an allergic type reaction. It occurs more specifically during l’ingestion sulphites, simple inhalation usually shows no symptoms. In the following minutes, the patient will experience various disorders:

• Itching;
• Sneezing;
• Runny nose ;
• Urticaria;
• Conjunctivitis;
•  Tired ;
• Pain in the abdomen;
•  Asthma.

In the most severe cases, for example in those already allergic to aspirin, the patient may go so far as to undergo a anaphylactic shock, which can go as far as unconsciousness or even a coma or cardiac arrest.

To confirm a suspicion of sulfite intolerance, tests should be carried out hospital or fromallergists. The diagnosis is made by the ingestion of small doses of sulfites, so-called ” provocation In order to observe and identify the patient’s reactions. Diagnostic errors are indeed frequent, real sulfite intolerance being rather rare.

This test says to ” reintroduction »Sulfites is more demanding for asthmatics, in whom we will ask to stop inhaled treatments 12 hours before the test, or bronchodilator six hours before.

Conduct of the examination 

The examination then begins with a study of the patient’s breath, using a dedicated device, the spirometer. It is simply a question of blowing to measure the respiratory capacities at rest. Blood pressure and pulse will also be taken as benchmarks. Then, we administer by oral (diluted in water) suspected sulfites, gradually increasing the dose until a patient reaction is observed. Skin tests, directly on the skin, can also be done.

As always with an allergy, the best (and almost only) solution is to ban foods containing sulphites. In the event of an attack following the ingestion of sulfites, one can be treated over a short period of time with a anti histaminique. Thereafter, it will be necessary to monitor its diet in order to avoid sulfites, or at least reduce the doses (given that this is only an intolerance, and not an allergy where the reaction would be inevitable) .

Given the nature of sulphites as preservatives in our food, it will therefore be necessary to be extra vigilant and know the compounds that can trigger a reaction. We can thus be careful with the compounds of the range E220 (from E220 to E228), classified to comply with European standards. To these are added other acids and chemical compounds to be avoided:

• Sulfurous acid;
• Sulfiting agent;
• Sulfur dioxide;
• Dithionite de sodium ;
• Potassium bisulfite;
• Sulphur dioxide.