Naturally Occurring Sulfites

Sulfites are naturally occurring compounds found in small amounts in many foods, including fruits, vegetables, and grains. They are also produced during fermentation processes, such as in wine and beer. While some sulfites occur naturally, they are also commonly added to foods as a preservative.

Added sulfites act as a preservative by preventing oxidation and inhibiting the growth of bacteria, yeast, and mold. This helps maintain the color and freshness of foods. They are often found in dried fruits, processed potatoes, wine, beer, and some baked goods.

The FDA considers sulfites generally recognized as safe (GRAS) when used as a preservative, but requires labeling when added in amounts of 10 parts per million or more. Some individuals, particularly those with asthma, may experience sensitivity reactions to sulfites. Regulatory bodies like the WHO/IARC and EFSA have evaluated sulfites. Evidence regarding the extent and prevalence of sulfite sensitivity is mixed, with some studies suggesting higher prevalence in asthmatics.