For more than 2000 years, sulfites have been used to prevent food spoilage and discoloration. Perhaps for nearly as long, they've played a more sinister role - causing allergic-type reactions in some of the people who consume them. Ellen Wiest is one such individual. She often suffered from headaches, severe nasal congestion, abdominal cramps and diarrhea after eating. But she didn't connect her symptoms to sulfites, until one June evening in 1995.
That night, Wiest was enjoying dinner with her husband at a favorite restaurant. Halfway through the meal, she developed symptoms typical of a food sensitivity. Only this time, they were accompanied by an increased heart rate, profuse vomiting and difficulty breathing. The restaurant called 911, and paramedics rushed her to the local emergency room.
Wiest learned that her meal contained a splash of wine, and sulfites in the wine sparked the anaphylactic reaction. Similar reactions to hidden sulfites have landed her in the ER twice since then. "When we eat out, I make it clear to the waiter that I will have a life-threatening reaction if I eat anything that contains sulfites," she notes. "Most of the time, I need to explain what sulfites are and what foods usually contain them."
While the severity of Wiest's reaction may be uncommon, sulfite sensitivity is not. The U.S. Food and Drug Administration estimates that up to one in 100 people may be sensitive to the chemicals. Among asthmatics, the ratio shoots to one in 10 and even higher among those who depend on corticosteroids.
Surrounded by Sulfites
In addition to their role as preservatives, sulfites are used to bleach food starches, such as corn, potato and sugar beet. Sulfites are also put to work as preventives against rust and scale in boiler water used in making steam that may come into contact with food.
Because sulfites inhibit fungal and bacterial growth, they are sprayed on both fresh grapes and those used in winemaking. Sulfites are a normal by-product of winemaking. Sulfites lurk in many popular foods and beverages, under the names of sulfur dioxide, sodium sulfite, sodium bisulfite, potassium bisulfite, sodium metabisulfite and potassium metabisulfite. Wine, bottled lemon and lime juices, and sulfur-dried fruits have the highest levels of sulfites.
The Labeling Nightmare
Avoiding sulfites can be difficult. "I've learned to carefully read labels," Wiest says. "But it's surprising how poorly many foods are labeled with regard to sulfites."
Current labeling laws were enacted in 1985, after sulfites were linked to 15 deaths. The Food and Drug Administration now say manufacturers must identify the presence of sulfites on food labels, but only if concentrations exceed 10 parts per million. Test strips are available to test liquid foods. However, they detect sulfites only in levels greater than 10 parts per million - and many sulfite-sensitive individuals react to much lower levels. |
