Understanding What Foods Have Sulfa in Them

December 12, 2025 •

3 min read

According to the American Academy of Allergy, Asthma & Immunology, sulfa drugs are not chemically related to sulfites or elemental sulfur, a distinction often confused by the public. To understand what foods have sulfa in them, it's essential to first differentiate between these related but distinct compounds and learn which foods contain sulfites, a common food preservative derived from sulfur.

Quick Summary

This guide explains the critical difference between sulfa (medications), sulfites (food preservatives), and the essential mineral sulfur found in many foods. It lists common foods containing sulfites and naturally high levels of sulfur, providing a clear overview for dietary management and health awareness.

Key Points

Sulfa is not in food: The term "sulfa" refers to sulfonamide antibiotics, and sulfa allergies are reactions to these medications, not to dietary components.
Sulfites are food additives: Sulfites, which are derived from sulfur, are used as preservatives in a wide range of processed foods, wines, and dried fruits.
Sulfur is an essential mineral: Sulfur is a natural mineral vital for health and found in many common foods, including eggs, meat, and vegetables.
Sulfite sensitivity is different from a sulfa allergy: A reaction to sulfites is a sensitivity or intolerance, not an allergy to sulfa drugs, and the conditions are not related.
Read labels for additives: Those with sulfite sensitivity should check food labels for sulfur dioxide, sodium bisulfite, or E numbers like E220–E228 to avoid triggering symptoms.
High-risk foods for sulfites: Dried fruits, wine, beer, processed potatoes, and deli meats are some of the highest risk foods for containing sulfite additives.
Natural sulfur is generally safe: There is no such thing as an elemental sulfur allergy, and most people can safely consume sulfur-rich foods.

Demystifying the Confusion: Sulfa, Sulfites, and Sulfur

When people ask "what foods have sulfa in them," they are typically concerned about a sulfa allergy. However, "sulfa" usually refers to sulfonamide antibiotics, not compounds found in food. A true sulfa drug allergy is a reaction to this type of medication and is not triggered by eating foods with sulfites or natural sulfur. Dietary reactions are usually linked to sulfites, used as food preservatives, or less commonly, to an intolerance to foods naturally high in the mineral sulfur.

Sulfites: Common Food Preservatives

Sulfites are added to many foods to prevent discoloration, stop bacterial growth, and extend shelf life. Some individuals, especially those with asthma, are sensitive to sulfites and may experience hives, wheezing, or even anaphylaxis. The FDA mandates sulfite labeling if the concentration is 10 parts per million or higher.

Common foods containing sulfites include:

Wine and Beer
Dried Fruits (especially light-colored ones)
Processed Meats
Processed Potatoes
Certain Condiments and Sauces
Seafood (sometimes treated for discoloration)

Elemental Sulfur: A Necessary Dietary Mineral

Elemental sulfur is a vital mineral for human health, unlike sulfa drugs and sulfite additives. It's found in essential amino acids, proteins, and enzymes. Dietary sulfur comes from many sources, and true allergies to elemental sulfur do not exist. While very high intake might cause digestive issues for some, this is different from a sulfite sensitivity.

Foods naturally high in sulfur include:

Protein-rich Foods (meat, eggs, fish, dairy)
Cruciferous Vegetables (broccoli, cabbage, kale)
Allium Vegetables (garlic, onions, leeks)
Legumes (soybeans, beans, lentils)
Nuts and Seeds

Clarifying Dietary Concerns: Sulfites vs. Sulfur

Distinguishing between a sulfite reaction and eating foods with natural sulfur is important for sensitive individuals. For example, a reaction to wine is likely due to added sulfites, not its natural sulfur content. Reading ingredient labels is crucial for those concerned.

Comparison Table: Sulfites vs. Elemental Sulfur


Feature	Sulfites (Preservatives)	Elemental Sulfur (Mineral)
Nature	Additive used to preserve foods and beverages.	Essential dietary mineral found naturally in many foods.
Chemical Relation	Derived from sulfur but is not the same thing.	Basic element required for bodily functions.
Health Concerns	Can trigger allergy-like symptoms, especially in asthmatics.	Not associated with allergies; essential for health.
Common Sources	Dried fruits, wine, processed potatoes, deli meats.	Meats, eggs, garlic, onions, cruciferous vegetables.
Labeling	Required by law for concentrations over 10ppm.	Not listed on labels; part of nutritional information.

Navigating Food Labels and Management

Managing a sulfite sensitivity means being careful about what you eat. Check ingredient lists for terms like "sulfur dioxide," "potassium bisulfite," "sodium sulfite," or E numbers E220-E228. Be cautious at places like salad bars where produce might be treated with sulfites, although this is becoming less common. If you have a diagnosed sensitivity, always carry prescribed emergency medication and talk to a healthcare professional or dietitian for dietary advice. Organizations like the Australasian Society of Clinical Immunology and Allergy can also provide helpful guidance.

Conclusion

The question "what foods have sulfa in them" often comes from confusing sulfa drugs, sulfites, and elemental sulfur. Sulfa refers to medications and is not found in food. Sulfites are food preservatives that can cause sensitivities, while elemental sulfur is a healthy mineral in many foods. For those managing sensitivities, avoiding sulfite additives is key to a safe diet, rather than avoiding all sulfur-containing foods.

For more detailed information on sulfite sensitivity, consult an authoritative resource like Allergy UK.

Frequently Asked Questions

No, a sulfa allergy is a reaction to sulfonamide antibiotics, not to any component found in food. Sulfites, which are food preservatives, are what people with dietary sensitivities react to.

Sulfites are preservatives derived from sulfur and added to food to prevent spoilage, inhibit bacterial growth, and maintain color. They are commonly found in dried fruits, wines, and processed foods.

Foods naturally high in sulfur include protein sources like meat, eggs, and fish; cruciferous vegetables like broccoli and cabbage; and allium vegetables like garlic and onions.

Symptoms of sulfite sensitivity can include wheezing, hives, or other asthma-like symptoms, particularly in individuals with pre-existing asthma. Diagnosis typically involves evaluation by a healthcare provider.

Yes, it is safe to eat foods naturally high in sulfur even if you have a sulfa drug allergy. The two are not chemically related, and consuming natural dietary sulfur does not pose a risk.

If you are avoiding sulfites, look for ingredients such as sulfur dioxide, sodium bisulfite, potassium bisulfite, and numbers E220 through E228 on food labels.

No, the sulfites found in wine do not affect people with sulfa allergies. The reaction is specific to the sulfa drug molecule, not the sulfur-containing preservatives or compounds.