What Are Sulfites?
Sulfites are chemicals that are commonly used as preservatives for a range of different types of foods and beverages. For example, sulfites are often added to shellfish to prevent discoloring, processed foods to give them a longer shelf-life, and dehydrated fruits and veggies to preserve them. You can also find these chemicals in soft drinks and alcoholic beverages like beer and wine. In addition, some medicines contain sulfites, which work to keep the drugs stable and effective.
Are Sulfites Safe?
The United States Food and Drug Administration (FDA) labels sulfites as “GRAS” (generally recognized as safe) in a variety of products. But, there are restrictions on how these agents can be used. For instance, the FDA does not allow this preservative on the raw veggies that you find at your favorite salad bar, since sulfites would make the veggies look fresh when they might not be.
And since the 1980s, the FDA has made companies identify food, drinks, and medicines that do contain sulfites. Why the need for this labeling? The FDA made the ruling after reports came in that people were having allergic—in some cases severe—reactions after eating or drinking a product containing sulfites.
What Is Sulfite Sensitivity?
You are considered to be sensitive to sulfites if you have an allergic reaction after consuming this preservative. The symptoms, which range from mild to severe, can include:
- Skin problems—itchy skin, rash, hives
- Digestive problems—stomach cramps, nausea, diarrhea
- Respiratory problems—wheezing, cough, difficulty breathing, tightness in the chest
In extreme situations, a life-threatening allergic reaction (called anaphylactic shock) may occur, where the person is not able to breath and experiences a drop in blood pressure.
How common is this sensitivity? Actually, the FDA estimates that the number of Americans who are allergic to sulfites is low. But people with asthma seem to have a higher risk of experiencing a reaction to these chemicals.
How Is It Diagnosed?
If you think that you may have sulfite sensitivity, one way an allergist can diagnose the condition is by doing a food challenge. This involves giving you a very small amount of the suspected allergen (in this case, sulfites) and closely observing you for any reaction. If you do not have any symptoms, the doctor will slowly increase how much of the allergen you are given. If you do have a reaction, medicine will be given to reverse your symptoms and tests can be done to check your lung function. A food challenge should only be done under close supervision by an allergist.
Another option for diagnosis is a skin prick test, where the suspected allergen is placed on the skin and then the area is pricked. If you have a reaction, like a bump on the skin, you may be allergic to sulfites.
How Can You Reduce Your Risk?
If you are sensitive to sulfites, the best approach is to avoid these chemicals. This can be difficult considering how common sulfites are in the foods we eat and the fact that they come in so many different forms—like sulfur dioxide, potassium bisulfate, and potassium metabisulfite.
Despite these obstacles, there are ways that you can live a sulfite-free lifestyle.
Know What to Look For
Here are some examples of products that commonly contain sulfites:
- Beer, wine, soft drinks
- Cookies, crackers, pie crust, pizza crust
- Dried fruit
- Shrimp, lobster, scallops
- French fries and other food made with peeled potatoes (eg, instant mashed potatoes)
- Fruit or vegetable juice
- Canned fruits or vegetables
- Syrup (eg, corn syrup, maple syrup) and fruit toppings
- Pickles, relish, olives, salad dressing
- Noodle or rice mixes, dried soup mixes
Check the Label
Since there are many other products that contain sulfites, carefully check the food label.
Keep in mind, though, that food prepared from bulk ingredients, like bakery bread with raisins in it, would have the sulfites label on the original bulk packaging. And, while the grocery store should list sulfites on the bread’s label, ask the store manager if you are concerned. You can use the same approach when dining out by asking the waiter or chef about the use of sulfites.
Search for Sulfite-Free
Since sulfite is such a common preservative, it is challenging to fill your kitchen with sulfite-free products. But there are options available, like specialty grocery stores and websites that sell health foods.
Check Your Medicine
Sulfites are added to many prescription and over-the-counter medicines. Surprisingly, this preservative is often found in drugs used to treat asthma and allergies. Other types of medicines that may have sulfites include:
- Drugs to treat vomiting and nausea
- Cardiovascular medicines
- Psychotropic drugs
- Medicines delivered intravenously (through a vein in the arm)
- Pain relievers
- Steroids and other medicines to help with respiratory problems
Read the drug label carefully. If you have any questions, talk to your doctor and pharmacist.
If you have been diagnosed with a severe allergy to sulfite, carry emergency medicine, like an asthma inhaler, with you at all times. You can also wear a medic alert bracelet to inform those around you that you have a food allergy.
In the case that you do have a reaction, get medical attention right away.
- Reviewer: Purvee S. Shah, MD
- Review Date: 05/2011 -
- Update Date: 05/03/2011 -