"Contains sulfites" is printed on most bottles of wine sold in the US, and plenty of people blame sulfites for their wine headaches, stuffy noses or flushed cheeks. Unlike some food sensitivities, such as MSG sensitivity, sulfite reactions have been confirmed in double-blind tests, and they can be dangerous: sulfites can trigger asthma attacks and, rarely, severe allergic-type reactions. Reports of serious reactions in the 1980s, including deaths, led the FDA to ban sulfites on salad bars.
But it is also less common than people think, it mostly affects people with asthma, and wine is often not the biggest source. This guide covers who reacts, which foods carry the most sulfite, what the red wine headache research shows, and whether supplements such as molybdenum or vitamin B12 help.
The short version
- Sulfites are preservatives (sulfur dioxide and five sulfite salts in the US) used in wine, dried fruit, bottled lemon juice, pickles, shrimp and processed potatoes. The body also makes sulfite from protein.
- Sensitivity is real but mostly limited to people with asthma. Reviews put it at 3 to 10 percent of adults with asthma; the most careful blinded study found under 4 percent, highest in severe asthma that needs regular steroid tablets. Reactions in people without asthma appear to be rare.
- Wine is usually not the main culprit. In one study only 4 of 24 people with "wine asthma" reacted to sulfites in wine, and only at a very high level. Under EU rules, dried apricots may carry 10 to 13 times more sulfite per kilogram than dry wine may per liter.
- Sulfites are an unlikely main cause of red wine headaches. European rules allow more sulfite in white wine than in dry red, yet headaches are mostly blamed on red.
- There is no reliable skin or blood test. An allergist confirms it with a supervised capsule challenge. Avoidance and good asthma control are the treatment.
- No supplement has good evidence. We found no human trial of molybdenum for sulfite sensitivity, and the vitamin B12 evidence is one small study in five children plus a case where it failed.
What sulfites are
US rules list six "sulfiting agents": sulfur dioxide, sodium sulfite, sodium bisulfite, potassium bisulfite, sodium metabisulfite and potassium metabisulfite (in Europe, E 220 to E 228; "sulphite" is the British spelling). They keep light-colored fruit and vegetables from browning, stop black spots forming on shrimp, curb bacteria in wine, condition dough, and keep some medicines stable.
These forms switch into one another depending on acidity. In acidic foods and drinks such as wine, lemon juice and pickles, more of the sulfite is released as sulfur dioxide gas, which irritates sensitive airways. That is one leading explanation for why sulfites mainly affect people with asthma.
Sulfite is also a normal product of metabolism. The body makes it when it breaks down the sulfur-containing amino acids in protein, and an enzyme called sulfite oxidase, which depends on the mineral molybdenum, converts it to harmless sulfate. Yeast also make small amounts of sulfite during fermentation, so no wine is entirely sulfite-free.
Sulfites and asthma: how common is sensitivity?
Less common than the internet suggests, and concentrated in people with asthma:
- Adults with asthma: in the key US study, 203 people with asthma were screened with sulfite capsules, and 12 of the 21 who reacted were rechecked double-blind (neither the patient nor the tester knew which capsule held sulfite); only 4 were confirmed. The best estimate was 3.9 percent, and people whose asthma needed regular steroid tablets were most at risk. A Spanish study of 44 steroid-dependent patients found 4.5 percent after blinded confirmation. Reviews quote a range of 3 to 10 percent, which includes less rigorous studies.
- Children with asthma: estimates swing with the test method. In one study, none of 29 children reacted to sulfite capsules, but 19 reacted when the same chemical was given in an acidic drink, which releases sulfur dioxide gas that many asthmatic airways react to.
- Everyone else: a 1996 FDA consumer article said 1 in 100 people is sulfite-sensitive, but it cited no study, and a 1995 review estimated up to 500,000 sensitive people in the US, about 0.2 percent of the population then (the review itself printed under 0.05 percent, which does not match its own number). In PubMed searches through November 2026, we found no population study that challenge-tested unselected adults. Reviews agree reactions in people without asthma are rare.
Is it an allergy? Usually not in the strict sense. Most reactions do not involve IgE, the antibody behind classic food allergies, and Europe's food safety agency (EFSA) notes that "most sulfite sensitivities are not true allergic reactions." Proposed mechanisms include sulfur dioxide gas released in the stomach and inhaled, nerve reflexes in the airways, and low activity of the enzyme sulfite oxidase, which has been suggested in a case report but not shown in a series of patients. A small number of people do have positive skin tests and IgE-type reactions, and allergists consider them the most at risk of anaphylaxis (a severe, whole-body allergic reaction that can be life-threatening).
Sulfite sensitivity and allergy symptoms
The most common reaction in people with asthma is wheezing, chest tightness and coughing, often within minutes: in a wine challenge study, the drop in lung function peaked at five minutes. Other reported reactions include hives, swelling, itching, flushing, a stuffy or runny nose, stomach pain, diarrhea and nausea, and, rarely, a drop in blood pressure or anaphylaxis. Most reactions are mild, but deaths have occurred. By 1985, six US deaths had been reported as allegedly linked to sulfites in restaurant food. A later report described a man with severe asthma who died of an asthma attack after a few sips of white wine containing 92 ppm (parts per million) sulfite.
Sulfites are rarely behind long-lasting hives. In a study of 100 people with chronic hives tested with 11 food additives including sulfite, none had a reaction confirmed on double-blind testing.
- Wheezing or trouble breathing that does not settle with your reliever inhaler, swelling of the lips, tongue or throat, faintness or collapse after eating or drinking. Use epinephrine if prescribed and call emergency services.
- The small amount of sulfite in epinephrine auto-injectors is not a reason to delay using one (see below).
Foods high in sulfites
Levels vary enormously between foods and brands. Legal limits give a sense of scale (actual products are usually below them):
| Food or drink | Legal maximum (as sulfur dioxide) |
|---|---|
| Dried apricots, peaches, grapes (raisins), prunes and figs (EU) | 2,000 mg/kg |
| Dried bananas (EU) | 1,000 mg/kg |
| Horseradish pulp (EU) | 800 mg/kg |
| Dried apples and pears (EU) | 600 mg/kg |
| Dehydrated potato products (EU) | 400 mg/kg |
| Lime and lemon juice (EU) | 350 mg/L |
| Wine (US) | 350 ppm (mg/L) |
| White and rose wine, dry (EU) | 200 mg/L |
| Red wine, dry (EU) | 150 mg/L |
EU limits from Regulation 1333/2008 as tabled by EFSA (2022) and wine Regulation 2019/934; US wine limit from 27 CFR 4.22. Sweet wines are allowed more.
Measured levels can be high: an FDA survey found up to 3,722 ppm in dried fruit, and a 1995 report traced a cluster of reactions to a salsa labeled "fresh" that averaged about 1,800 ppm. Other common sources include molasses, maraschino cherries, jams, soup mixes, gravies, some beers and ciders, vinegar, pickled vegetables, shrimp, and pre-peeled, fresh-cut or dehydrated potatoes (including some restaurant fries and hash browns). US rules do not allow sulfites in meat, but Europe permits them in some sausages and burger meat, which matters when traveling.
The same amount of sulfite does not always cause the same reaction. In one challenge study of eight people with confirmed sensitivity, two of the three tested reacted to dried apricots, none reacted to sulfited shrimp, and four reacted to none of the foods tested. "Free" sulfite, as on sulfite-treated lettuce, seems more likely to cause trouble than sulfite bound up in the food.
Lists online often include eggs, onions, garlic and cabbage as "high-sulfite" foods. They are rich in sulfur compounds, and natural compounds in the onion and cabbage families can show up as sulfite in the standard lab test, but that is not the same as added sulfites.
Sulfites in wine and red wine headaches
Wine is the food most associated with sulfites, largely because of the label. A glass of dry red wine (150 mL) at the European limit would contain at most about 22 mg of sulfur dioxide; 40 grams of dried apricots at their limit could contain up to 80 mg.
Studies of people who blame wine for their asthma rarely confirm sulfites as the cause. In a 2001 study, 24 people with a strong history of wine-induced asthma were tested; only 4 reacted to sulfites in wine, and those 4 reacted only to wine containing 300 ppm sulfite, not to 20, 75 or 150 ppm. In a 2007 double-blind study, none of 8 people with wine-related asthma had a significant drop in lung function after high- or low-sulfite wine. Alcohol itself, histamine, venom proteins from insects caught up in grape pressing (one report found wine reactors sensitized to them who reacted to young wines but not to sulfites), and other wine components have all been implicated instead (see our histamine intolerance guide).
Do sulfites cause red wine headaches?
If sulfites were the main cause, white wine should be worse, since European rules allow more sulfite in white wine than in dry red. A 2014 review reported that red wine, but not white or sparkling wine, triggered headaches in fewer than 30 percent of people studied, and pointed to other red wine compounds; it also noted that most of these studies had been presented only as meeting abstracts. A 2023 lab study proposed one candidate: a quercetin compound found mainly in red wine blocked an enzyme that clears acetaldehyde, a toxic breakdown product of alcohol. The authors stressed that this needs testing in people.
One small 2019 study, with a wine-industry co-author and unclear reporting, suggested that sulfite level might matter for people with a history of wine headaches. Overall, sulfites are an unlikely main cause of the typical red wine headache, but the evidence is thin either way. See our guide to supplements and alcohol for more on drinking and supplements.
Is there sulfite-free wine?
Not entirely, because yeast make some. "No sulfites added" wines can still contain some, and a US wine must say "Contains sulfites" when it has 10 ppm or more. Under USDA organic rules, wine "made with organic grapes" may have added sulfur dioxide, up to 100 ppm total sulfite. We found no study testing the wine drops or filters sold to remove sulfites in people with sulfite sensitivity; the only PubMed study we found of such a device measured acidity, oxidation, color and taste, not sulfite levels or symptoms.
Labels and the law
- US food labels: sulfites added for a purpose must be listed, and sulfites carried in from another ingredient must be listed at 10 ppm or more. So a label that does not list sulfites is not a guarantee of zero.
- The 1986 FDA ban: sulfites may not be used on fruit and vegetables served or sold raw, such as salad bars, guacamole and fresh mushrooms. Older limits in the same rules also bar them from meat and from foods that are a source of vitamin B1 (thiamine), because sulfite destroys it. A later attempt to ban sulfites on fresh-cut potatoes was overturned in court, so restaurant potatoes can still be treated.
- Restaurants: a 1996 FDA consumer article noted that restaurants were not required to tell you whether sulfites were used, so ask.
- Wine: "Contains sulfites" is required at 10 ppm or more.
- Europe: sulfites above 10 mg/kg or 10 mg/L must be highlighted as one of 14 major allergens. In 2022, EFSA withdrew its temporary daily limit and raised a safety concern about high long-term intakes, based on an effect on nerve signaling in rats. That is a separate question from sensitivity reactions. The WHO and FAO expert committee (JECFA) set an acceptable daily intake (the amount considered safe to eat every day over a lifetime) of 0 to 0.7 mg per kg of body weight.
Some supplements may contain sulfiting agents too, as preservatives. If you are sensitive, check the "Other ingredients" line for sodium metabisulfite or the other names above; our guides to supplement "other ingredients" and reading a Supplement Facts label explain where to look.
Is there a test for sulfite sensitivity?
Not a simple one. Skin prick and blood tests are usually negative, even in people who react, because most reactions do not involve IgE. The accepted test is an oral challenge supervised by an allergist: small, increasing doses of sulfite in capsules (up to roughly 100 to 200 mg of metabisulfite), compared with a placebo, while lung function is monitored. Low-dose capsule challenges give fewer false alarms than acidic sulfite drinks, but a positive result on single-blind screening still needs double-blind confirmation: in the key US study, only 4 of the 12 people rechecked were confirmed. Capsules can also miss many people: in one German study, only about 40 percent of people with a history of sulfite-triggered asthma reacted to capsules. Acidic sulfite drinks pick up more reactions but also more false alarms.
Never test yourself with wine or dried fruit, and never stop asthma medicine before a challenge unless your allergist tells you to; experts run these tests with patients on their usual medicines.
Living with sulfite sensitivity
- Avoid the main sources you react to and read labels for the six sulfite names. One review describes excellent outcomes from modest changes to diet and habits.
- In restaurants, ask about sulfites. A doctor quoted in a 1996 FDA consumer article suggested ordering a baked potato rather than fries, hash browns or any dish made from pre-peeled potatoes; also be cautious with dried fruit, maraschino cherries, guacamole, salsa and shrimp.
- Keep asthma well controlled and carry your reliever inhaler. Reactions cluster in severe or poorly controlled asthma.
- Carry epinephrine if prescribed. The FDA label for EpiPen notes that it contains sodium metabisulfite but states that "the presence of a sulfite in EpiPen or EpiPen Jr should not deter administration of the drug" in an emergency.
- Tell your doctors and dentist. Some injectable medicines and local anesthetics that contain epinephrine include sulfites; ask whether a sulfite-free option is available. A 2012 review notes that albuterol, unlike some older asthma solutions, does not contain sulfites.
Molybdenum for sulfite sensitivity, B12 and other supplements
Does molybdenum help sulfite sensitivity? Because sulfite oxidase needs molybdenum, supplement sellers promote molybdenum (often as molybdenum glycinate) for sulfite sensitivity. The biology is plausible, but we found no human trial or case series testing it in sulfite-sensitive people, in PubMed searches through November 2026. Molybdenum deficiency has essentially never been reported in people eating normal diets; the NIH notes it only in people with rare genetic defects and in one patient fed intravenously without molybdenum. Those genetic sulfite oxidase disorders are severe illnesses that usually start in newborns and are not treated with molybdenum supplements. For adults, the Recommended Dietary Allowance (RDA) is 45 mcg a day and the tolerable upper intake level (the most considered safe from all sources) is 2,000 mcg. If you try it, stay well under that limit and keep avoiding sulfites.
Vitamin B12. Vitamin B12 (as cyanocobalamin) is thought to react with sulfite chemically. In a 1992 Spanish study of five children with asthma and confirmed sulfite sensitivity, 1.5 mg of oral B12 taken before a repeat challenge prevented wheezing in four of the five; no placebo comparison was described. In a later case from the same hospital group, 5,000 mcg of B12 did not prevent hives from sulfite. An adult study often cited online does not appear to have been published as a full paper. B12 is low risk, but it is not a substitute for avoidance or epinephrine, and we found no evidence for taking it before drinking wine.
Other options. Small studies from the 1970s to 1990s found that the asthma medicine cromolyn reduced some sulfite-triggered airway reactions, though it did not stop hives in one case; that is a decision for an allergist. In PubMed searches through November 2026, we found no controlled study of antihistamines or doxepin taken beforehand to prevent reactions to sulfite in food.
Sulfates, sulfa drugs and sulfur foods are different
"Sulfite," "sulfate," "sulfa" and "sulfur" sound alike but are not the same:
- Sulfates are what the body turns sulfite into. Supplements such as glucosamine sulfate, chondroitin sulfate, magnesium sulfate, zinc sulfate and ferrous sulfate contain sulfate, not sulfite, and none is on the US list of sulfiting agents.
- MSM (methylsulfonylmethane) is a sulfur compound, not a sulfite.
- Sulfur-rich foods such as eggs, onions, garlic and cabbage contain natural sulfur compounds, not added sulfites (see foods high in sulfites).
- "Sulfa allergy" means an allergy to sulfonamide antibiotics. As one pharmacology review puts it, a person with a sulfa allergy "is not allergic to drugs containing sulfur, sulfites, or sulfates."
Frequently asked questions
What is sulfite sensitivity?
It is an adverse reaction to sulfites, preservatives used in wine, dried fruit, bottled lemon juice, pickled foods, shrimp and processed potatoes. The most common reaction is wheezing or an asthma attack in people who already have asthma; hives, flushing, stomach upset and, rarely, anaphylaxis can also occur.
Is sulfite sensitivity an allergy?
Usually not in the strict sense. Most reactions do not involve IgE, the antibody behind classic food allergies, and skin and blood tests are usually negative. A small number of people do have IgE-type reactions, and allergists consider them at highest risk of anaphylaxis. In the EU, sulfites are still labeled as one of the 14 major allergens.
How common is sulfite sensitivity?
Reviews estimate 3 to 10 percent of adults with asthma, and the most careful blinded US study found under 4 percent, highest in people with severe, steroid-dependent asthma. Reactions in people without asthma appear to be rare. The often-quoted 1 in 100 figure comes from a 1996 FDA consumer article that cited no study.
Can sulfites trigger an asthma attack?
Yes, in a minority of people with asthma. Reviews estimate 3 to 10 percent of adults with asthma, and the most careful blinded study found under 4 percent. Wheezing, chest tightness and coughing are the most common sulfite reactions and often start within minutes. People with severe asthma that needs regular steroid tablets are most at risk. Keep asthma well controlled, carry your reliever inhaler, and get emergency help if breathing does not improve with it.
Do sulfites cause red wine headaches?
Probably not, at least not as the main cause. European rules allow more sulfite in white wine than in dry red wine, yet headaches are mostly blamed on red. Researchers have proposed other red wine compounds instead, though none is proven. Dried fruit can contain far more sulfite than wine.
Does white wine have more sulfites than red?
Not necessarily, but it is allowed to. European rules let dry white and rose wine carry up to 200 mg per liter of sulfur dioxide, compared with 150 mg per liter for dry red, and sweet wines are allowed more; US rules set one limit of 350 ppm for all wine. These are legal maximums, not measured levels, and actual levels vary by winemaker. The higher allowance for white wine is one reason sulfites are considered an unlikely main cause of red wine headaches.
Which foods have the most sulfites?
Dried fruit, especially light-colored dried apricots, golden raisins and dried peaches, can contain the most, with legal limits up to 2,000 mg per kg in the EU. Other common sources are bottled lemon and lime juice, horseradish, pickled vegetables, molasses, maraschino cherries, jams, soup mixes, shrimp, wine, beer, cider and pre-peeled or dehydrated potatoes.
Is there sulfite-free wine?
Not entirely, because yeast make small amounts of sulfite during fermentation. Wines labeled "no sulfites added" can still contain some. In the US, a wine must say "Contains sulfites" when it has 10 ppm or more, and wine made with organic grapes may contain up to 100 ppm total sulfite.
How is sulfite sensitivity diagnosed?
By an oral challenge supervised by an allergist: increasing doses of sulfite in capsules compared with a placebo, while breathing is monitored. Skin and blood tests are not reliable. Never test yourself with wine or dried fruit, and do not stop asthma medicine unless your allergist tells you to.
Can you use an EpiPen if you are sensitive to sulfites?
Yes. EpiPen contains a small amount of sodium metabisulfite, but its FDA label states that the presence of a sulfite should not deter use of the drug in a serious allergic reaction or other emergency. Epinephrine remains the preferred emergency treatment.
Does molybdenum or vitamin B12 help sulfite sensitivity?
There is little evidence. Molybdenum is needed by the enzyme that breaks down sulfite, but we found no human trial testing it for sulfite sensitivity. For vitamin B12, one 1992 study in five children found that 1.5 mg taken before a sulfite challenge prevented wheezing in four, without a placebo comparison, and B12 failed in a later case. Neither replaces avoidance or epinephrine.
If you are sensitive to sulfites, do you need to avoid sulfates or sulfa drugs?
No, these are different chemicals. Sulfates, such as glucosamine sulfate, magnesium sulfate or zinc sulfate, are what the body turns sulfite into, and a sulfa allergy is an allergy to sulfonamide antibiotics, not to sulfites or sulfates. Ask your doctor or pharmacist if you are unsure about a specific product.
The bottom line
Sulfite sensitivity is a real, sometimes serious reaction, but it mostly affects people with asthma, especially severe asthma, and is rare in everyone else. Dried fruit, bottled lemon juice, pickled foods and restaurant potatoes can carry more sulfite than wine, and sulfites are an unlikely main cause of red wine headaches.
If you suspect a reaction, see an allergist rather than testing yourself, keep asthma under control, read labels, and carry epinephrine if it has been prescribed. Molybdenum and vitamin B12 supplements have little or no human evidence for sulfite sensitivity and should not replace avoidance.
