Is Sodium Bisulfite Bad for You in Food? Understanding the Facts

January 2, 2026 •

3 min read

According to the U.S. Food and Drug Administration (FDA), sodium bisulfite is a "Generally Recognized as Safe" (GRAS) food additive, but for some individuals with specific sensitivities, it can cause adverse reactions. This common preservative is used to maintain freshness and prevent discoloration in various processed foods.

Quick Summary

This article explores the safety of sodium bisulfite in food, outlining its uses as a preservative and antioxidant. It details potential health concerns for sensitive individuals, such as those with asthma, and clarifies its regulatory status with health authorities like the FDA.

Key Points

Generally Safe: Sodium bisulfite is affirmed as "Generally Recognized as Safe" (GRAS) by the FDA for most people when consumed within regulated amounts.
Risk for Asthmatics: Individuals with asthma or sulfite sensitivity may experience adverse reactions, including respiratory issues like wheezing, chest tightness, or coughing.
Mandatory Labeling: Foods containing more than 10 ppm of sulfites must be labeled, which is vital for sensitive consumers to avoid.
Degrades Vitamin B1: Sodium bisulfite can destroy vitamin B1 (thiamine), leading to regulations that ban its use on fresh meats.
Food Uses: It primarily serves as a preservative, antioxidant, and anti-browning agent in a variety of processed foods.
Common Foods: Look for sulfites in dried fruits, wines, certain baked goods, and processed potato products.

What is Sodium Bisulfite?

Sodium bisulfite ($NaHSO_3$) is an inorganic salt widely used as a food additive. It functions as an antioxidant and preservative by releasing sulfur dioxide ($SO_2$) under acidic conditions, which inhibits microbial growth and prevents browning. It is available in food-grade form, adhering to strict purity standards.

How is Sodium Bisulfite Used in Food?

Sodium bisulfite is used in food for several purposes to improve shelf life and appearance:

Preservation: It prevents the growth of bacteria, yeast, and molds.
Antioxidation and Anti-Browning: It stops oxidation that causes discoloration and rancidity, particularly preventing enzymatic browning in items like dried fruits and shrimp.
Dough Conditioning: It acts as a reducing agent in baking, making dough for crackers and biscuits more pliable.

Potential Health Concerns for Sensitive Individuals

While safe for most people, sulfites, including sodium bisulfite, can cause adverse reactions in a small percentage of individuals, especially those with asthma. Symptoms can include:

Respiratory issues: Wheezing, chest tightness, coughing, or shortness of breath.
Allergic-type reactions: Skin irritations, hives, swelling, and rarely, anaphylaxis. It's an intolerance, not a true allergy, though symptoms are similar.
Digestive problems: Abdominal cramps, nausea, or diarrhea.

Sodium Bisulfite and Vitamin B1

Sodium bisulfite can degrade vitamin B1 (thiamine), reducing its nutritional value in certain foods. This effect is a factor in regulations prohibiting its use on fresh meats, which are a source of this vitamin.

How to Identify Sodium Bisulfite in Food

Foods containing over 10 ppm of sulfites must be labeled in the U.S.. Look for "sodium bisulfite" or its E-number, E222, on ingredient lists. Other sulfites like sodium sulfite (E221) and potassium metabisulfite (E224) may also be listed.

Comparison of Sulfite Additives


Feature	Sodium Bisulfite	Sodium Metabisulfite	Sodium Sulfite
Chemical Formula	$NaHSO_3$	$Na_2S_2O_5$	$Na_2SO_3$
Effectiveness	Strong antioxidant and preservative	Stronger reducing agent, highly effective	Weaker reducing agent
pH of Solution	Mildly acidic	Acidic	Alkaline
Common Uses	Dried fruits, wine, baked goods	Wine, beer, dried fruits	Water treatment, photography

Conclusion

Regulatory bodies like the FDA consider sodium bisulfite safe for most consumers at approved levels. The main concern is for sulfite-sensitive individuals, particularly those with asthma, who may experience adverse reactions. Reading food labels to identify sulfites like sodium bisulfite (E222) is essential for managing intake. While sulfites can reduce vitamin B1 in some foods, this is generally not a health risk with a balanced diet. If you suspect a sulfite sensitivity, consult a healthcare professional. For further details on food additives, the FDA website is a valuable resource.

Common Foods Containing Sulfites

Dried fruits: Often treated to preserve color.
Wine and beer: Natural byproduct and added preservative.
Baked goods: Some crackers and biscuits for texture.
Processed potatoes: Used to prevent browning.
Bottled lemon and lime juice: Added as an antioxidant.

Key Takeaways

Regulatory Safety: The FDA classifies sodium bisulfite as GRAS for the general population within approved amounts.
Risk for Asthmatics: Sensitive individuals, especially those with asthma, may experience adverse reactions, including respiratory issues.
Label Awareness: Foods with over 10 ppm sulfites must be labeled; look for "sodium bisulfite" or E222.
Nutrient Impact: Can reduce vitamin B1 content, leading to bans on fresh meats.
Common Applications: Used as a preservative, antioxidant, and anti-browning agent.
Not Carcinogenic: No significant link to cancer risk in food applications.
Not a True Allergy: Sulfite sensitivity is an intolerance with similar symptoms to an allergy.

Frequently Asked Questions

For the general population, sodium bisulfite is not considered toxic in the small amounts used in food, and regulatory bodies like the FDA have deemed it safe for consumption. Toxicity is primarily a concern with very high, concentrated doses, far beyond what is found in food.

While not a true allergy, sulfites can trigger allergic-type reactions or intolerances, particularly in sensitive individuals. Symptoms can range from mild skin rashes and digestive discomfort to severe respiratory problems like wheezing, especially for those with asthma.

Sodium bisulfite is found in a range of processed foods, including dried fruits, wine, canned and frozen fruits and vegetables, certain baked goods, and bottled lemon and lime juices.

The FDA prohibits the use of sulfites, including sodium bisulfite, on fresh fruits and vegetables and on fresh meats. This is partly because it can destroy vitamin B1 (thiamine) and can give fresh produce a false appearance of freshness.

To avoid sodium bisulfite, you should read food labels carefully, especially for processed and packaged foods. Look for 'sulfites,' 'sodium bisulfite,' or the E-number 'E222' on the ingredient list. Choosing fresh, unprocessed foods is the most direct way to avoid this additive.

No, while they belong to the same family, different sulfites (e.g., sodium bisulfite, sodium metabisulfite) have slight chemical differences that affect properties like their solubility and the pH of their solutions. However, all can cause reactions in sensitive individuals.

A sulfite sensitivity or intolerance is a negative reaction to sulfites that is not an immune-system response like a true allergy. While a true allergic reaction involves IgE antibodies, sulfite sensitivity triggers similar symptoms like asthma attacks or skin rashes without involving the same immune pathway.