Sulfite is a chemical compound that contains the sulfite ion, which consists of sulfur and oxygen. It is commonly used as a preservative in food and beverages, particularly in products like dried fruits and wine, to prevent spoilage and maintain freshness. Sulfites can also occur naturally in some foods and are produced during fermentation. Some people may have sensitivities or allergies to sulfites, which can lead to adverse reactions such as headaches or asthma symptoms. Because of this, food labels often indicate the presence of sulfites, allowing consumers to make informed choices about products containing this compound, especially in relation to wine and dried fruits.