Sulfites or sulphites are compounds that contain the sulfite ion . Although its acid (sulfurous acid) is elusive, its salts are widely used.
- Sulfites are used as a food preservative or enhancer.
- Sulfites, when used as a preservative, are inorganic salts that help extend the shelf life of certain foods. The salts are used to keep foods from turning brown, to prevent the growth of bacteria and to help maintain the stability of certain medications. Sulfites also occur naturally as part of the fermentation process in foods such as beer and wine.
- Sulfites are counted among the top nine food allergens, but a reaction to sulfite is not a true allergy. Some people have positive skin allergy tests to sulfites indicating true (IgE-mediated) allergy.
- It may cause breathing difficulty within minutes after eating a food containing it. Asthmatics and possibly people with salicylate sensitivity (or aspirin sensitivity) are at an elevated risk for reaction to sulfites. Anaphylaxis and life-threatening reactions are rare.
- Other potential symptoms include sneezing, swelling of the throat, hives, and migraine
Source: Wikipedia, https://en.wikipedia.org/wiki/Sulfite#Health_effects