Are Sulphites Bad for You? Separating Myth from Fact

According to the U.S. Food and Drug Administration (FDA), only about 1% of the population suffers from sulphite sensitivity. So, are sulphites bad for you? While generally safe for most, these common preservatives can cause adverse reactions in a small percentage of individuals, particularly asthmatics.

Quick Summary

This article explores the health effects of sulphites, discussing why they are used in food and beverages, identifying those most at risk for adverse reactions, and providing guidance on managing sensitivity through label reading and food avoidance.

Key Points

• Generally Safe for Most: For the majority of people, sulphites are considered safe and harmless in the amounts used in food and beverages.

• Higher Risk for Asthmatics: Individuals with asthma are at a significantly higher risk of experiencing adverse reactions, with up to 13% affected by sulphite sensitivity.

• Sensitivity, Not Allergy: Reactions to sulphites are typically sensitivities or intolerances, not true IgE-mediated allergies, although they can produce allergy-like symptoms.

• Found in Many Foods: Sulphites are common preservatives in dried fruits, wines, beers, and many processed foods; labels are required to declare them above certain concentrations.

• Avoidance is Key for Sensitive Individuals: The most effective way to manage sulphite sensitivity is to identify and avoid foods, drinks, and medications that contain them.

• Red Wine Headache Myth: Research suggests sulphites are likely not the cause of red wine headaches; other compounds like histamines are more probable culprits.

What Exactly Are Sulphites?

Sulphites are a group of sulfur-based chemical compounds that act as preservatives and antioxidants. They are widely used in the food and pharmaceutical industries to prevent spoilage, maintain food color, and extend shelf life. The most common sulphite is sulfur dioxide (SO2), which can be added directly or produced naturally during fermentation in items like wine and beer. Other sulphite names to look for on labels include sodium sulphite, sodium bisulphite, sodium metabisulphite, potassium bisulphite, and potassium metabisulphite.

Sulphites' Role in Food Preservation

For thousands of years, sulphites have been used to preserve food. Their primary functions include:

• Antioxidant: They prevent or slow down browning and discoloration, which is particularly important for products like dried fruit and some seafood.
• Antimicrobial: They inhibit the growth of bacteria and yeast, preventing spoilage and helping maintain freshness.
• Bleaching: Some sulphites are used to bleach food starches and food packaging.

Understanding Sulphite Sensitivity and Adverse Reactions

While the FDA considers sulphites "Generally Recognized as Safe" (GRAS) for the majority of the population, adverse reactions are a concern for sensitive individuals. It is crucial to distinguish between a true sulphite allergy and a sensitivity, as sulphite reactions are typically not IgE-mediated immune responses, but rather allergy-like intolerances.

Symptoms of Sulphite Sensitivity

In sensitive individuals, ingestion of sulphites can trigger a range of symptoms, most commonly affecting the respiratory system. People with asthma are at a higher risk of experiencing reactions.

• Respiratory: Wheezing, chest tightness, coughing, and shortness of breath. The release of sulfur dioxide gas from ingested sulphites can irritate the airways and cause them to constrict.
• Skin: Hives (urticaria), skin rashes, and flushed skin.
• Digestive: Abdominal pain, cramping, nausea, vomiting, and diarrhea.
• Rare, Severe Reactions: In very rare cases, anaphylaxis can occur, which involves more severe symptoms like swelling of the face and throat, rapid heartbeat, dizziness, and collapse.

The Red Wine Headache Myth

A persistent myth attributes red wine headaches to sulphites. However, research suggests that sulphites are an unlikely cause, as white wines generally contain more sulphites than red wines to protect them from oxidation. Other compounds in wine, such as histamines, tannins, and the alcohol itself, are more probable culprits.

Foods and Drinks Containing Sulphites

Sulphites can be found in a surprising number of food and drink products. Due to regulations in many countries, manufacturers are required to declare sulphites on labels if they exceed a certain concentration (e.g., 10 parts per million).

Common High-Sulphite Items

• Dried Fruits: Dried apricots, raisins, and other fruits often have very high sulphite levels to preserve their colour.
• Wine and Beer: Sulphites occur naturally during fermentation and are often added by winemakers to prevent oxidation and spoilage.
• Processed Meats: Sausages, hot dogs, and processed deli meats frequently contain sulphites.
• Condiments and Sauces: Pickles, sauerkraut, and some salad dressings may contain sulphites.
• Baked Goods: Some crackers and pizza dough can be made with sulphite additives.
• Other: Molasses, certain bottled juices, and pre-cut vegetables.

Comparison Table: Sulphites in Common Foods

Food Item	Typical Sulphite Concentration	Note
Dried Apricots	Up to 2,000 ppm	Very high concentration; used for colour preservation.
White Wine	Typically 250-450 mg/L	Higher levels than red wine due to less natural protection.
Red Wine	Typically 50-350 mg/L	Lower levels due to natural tannins acting as antioxidants.
Bottled Lemon Juice	Over 100 ppm	Used as a preservative.
Potatoes (Dehydrated)	50-99 ppm	Prevents browning and spoilage.
Fresh Grapes	Naturally occurring	Low levels, used for preservation during transport.
Most Dried Fruit (excluding dark)	Over 100 ppm	High levels, used to maintain appearance.

How to Manage Sulphite Sensitivity

If you suspect you have a sulphite sensitivity, the best course of action is to consult a healthcare professional for a proper diagnosis. In the absence of a reliable blood or skin test for sensitivity, a doctor may recommend a food exclusion and reintroduction diet under professional supervision. Once diagnosed, managing the condition primarily involves avoiding foods and drinks that trigger symptoms.

Practical Tips for Avoiding Sulphites

1. Read Labels Diligently: Always check ingredient lists for sulphite compounds (E220–E228) and the allergen declaration, which is often in bold.
2. Be Wary of Unpackaged Foods: Deli meats, bulk dried fruits, and restaurant food may contain undeclared sulphites.
3. Use Fresh Alternatives: Opt for fresh fruits, vegetables, meat, and fish over pre-processed or dehydrated versions.
4. Ask When Dining Out: Inform restaurant staff of your sensitivity, as some ingredients like pickled vegetables or dressings can contain hidden sulphites.
5. Look for 'No Added Sulphites' Labels: While all wine contains some naturally occurring sulphites from fermentation, some winemakers avoid adding more during the process.

Conclusion

While the vast majority of the population can consume sulphites without any adverse effects, they can present a real and serious problem for a small percentage of individuals, particularly asthmatics. Understanding what sulphites are, where they are found, and how to identify them on labels is key to managing sensitivity. For those who react, avoidance is the most effective treatment, and professional medical advice is essential for a correct diagnosis and management plan. The widespread use of sulphites as a preservative is a testament to their effectiveness, but for those with a sensitivity, vigilance is required to protect their health.

For more information, the Australasian Society of Clinical Immunology and Allergy provides a useful factsheet on sulfite sensitivity.

Frequently Asked Questions

What are sulphites?

Sulphites are a group of sulfur-based chemical compounds, also known as sulfur dioxide, that are used as preservatives and antioxidants in many food products, beverages, and pharmaceuticals.

Are sulphites bad for you if you don't have an allergy?

For the vast majority of the population, consuming sulphites is considered safe. Regulatory bodies worldwide have approved them for use in food preservation.

Who is most at risk for a sulphite reaction?

People with asthma are most at risk for sulphite sensitivity, with an estimated 5-13% experiencing adverse, allergy-like symptoms.

How can I tell if a food contains sulphites?

In many countries, sulphites must be declared on food labels if they exceed 10 parts per million. Look for the names 'sulphites', 'sulfur dioxide', or the E numbers E220-E228 in the ingredients list or allergen section.

Do all wines contain sulphites?

All wines contain naturally occurring sulphites as a byproduct of fermentation. However, winemakers often add more. Wines without added sulphites still contain natural traces.

Do sulphites cause headaches from wine?

It is a common myth that sulphites cause wine headaches. Other compounds like histamines and tannins, or dehydration, are more likely to be the cause.

Can cooking or washing remove sulphites?

No, sulphites cannot be removed by washing or cooking. The only way to avoid them is to not consume the food product.