Sulfites in Wine: What They Are and Why They're There

You’ve heard the line at a dinner party. “I can’t drink red wine, the sulfites give me a headache.” It’s repeated so often it sounds like settled science. It isn’t. The sulfite-headache theory has been studied repeatedly and never held up, while the actual culprits behind that next-day fog are sitting right next to you on the table: tannins, biogenic amines, dehydration, and the alcohol itself.

This guide explains what sulfites really do, why the warning label exists, and what’s probably actually going on when wine doesn’t sit right with you.

By the end of this page you’ll know:

• Why even “no sulfite added” wine still contains sulfites
• The 1988 US rule that put “Contains Sulfites” on every American label, and what triggered it
• The food in your pantry with ten times the sulfites of a glass of wine
• The four real causes of wine headaches that get blamed on sulfites
• Why natural wine without preservatives spoils faster, and what to look for when buying it

What Are Sulfites in Wine?

Sulfites are sulfur-based compounds, most commonly sulfur dioxide (SO2), that act as a preservative and antioxidant. Winemakers have used them for thousands of years because they do two important jobs: they slow down oxidation (which turns wine flat and brown) and they suppress unwanted bacteria and wild yeasts (which can spoil a finished wine).

There are two ways sulfites end up in your glass. The first is natural. Yeast produces a small amount of sulfite as a byproduct of fermentation, typically 6 to 40 parts per million (ppm). The second is added. Most winemakers add a controlled dose of SO2 at one or more points: at the crusher, after fermentation, before bottling. This brings the total to a level that protects the wine through years of storage.

Even wines marketed as “no added sulfites” or “zero sulfite” contain the natural fermentation sulfites. Truly sulfite-free wine doesn’t exist outside a lab.

Why Does Every Bottle Have Sulfites?

Because without them, wine doesn’t keep. Sulfur dioxide does three things that nothing else does as well:

• Stops oxidation. SO2 binds to oxygen molecules before they can attack the wine, preserving fresh fruit aromas and stopping the colour from browning.
• Kills off unwanted microbes. It suppresses spoilage yeasts like Brettanomyces (which can give wine barnyard or bandage notes) and acetic acid bacteria (which turn wine into vinegar).
• Locks in stability. A finished wine with the right SO2 level stays stable for years. Without it, you have a few months at best.

Without sulfites, the bottle of Bordeaux you cellared for ten years would have turned to brown, oxidised, possibly vinegar-tinged sludge by year three. Sulfites are why wine is wine and not, eventually, salad dressing.

How Many Sulfites Are in a Glass of Wine?

Less than most people think. The legal upper limit varies by region, but typical levels are:

• Dry red wine: 50 to 100 ppm total sulfites
• Dry white wine: 80 to 150 ppm
• Sweet white wine: 200 to 250 ppm (sugar is harder to stabilise, so more SO2 is needed)
• Sparkling wine: 100 to 150 ppm

Whites generally need more sulfites than reds because reds have natural antioxidants from grape skins (tannins and polyphenols) that take some of the preservative load. Sweet wines need the most because residual sugar invites bacterial trouble.

The European Union caps total sulfites at 150 ppm for dry red, 200 ppm for dry white, and up to 400 ppm for some sweet wines. Most quality producers operate well below the cap.

Why Does the US Label Say “Contains Sulfites”?

In 1986, the FDA banned sulfites as a preservative on raw fruits and vegetables (after several severe asthmatic reactions in restaurant salad bars). In 1988, they extended a labelling requirement to wine, beer, and packaged foods: anything with more than 10 ppm of sulfites had to declare it on the label.

Since virtually every wine has more than 10 ppm just from natural fermentation, the warning shows up on practically every American bottle. European labels carry similar disclosures under different language (“contains sulphites” / “contient des sulfites”).

The real medical concern is narrow. Roughly 1% of the general population has a true sulfite sensitivity, and within that group, it’s mostly people with severe asthma, particularly those who use steroid inhalers. For them, sulfite reactions can be serious and look like an asthma attack: wheezing, chest tightness, hives. If you’re in that group, you already know it, and you’d react to dried apricots and processed potatoes too.

Do Sulfites Cause Wine Headaches?

The evidence says no. This is one of the most studied wine myths, and study after study has failed to find a connection between sulfite levels and headaches in non-asthmatic drinkers. The theory was never well-supported. It got popular because “sulfites” appeared on the label and people needed something to blame.

Here’s what’s almost certainly causing the headache instead:

• Alcohol itself. Ethanol is a vasodilator and a diuretic. It widens blood vessels (which can trigger migraines in susceptible people) and dehydrates you (which causes the classic dehydration headache). The more alcohol, the more risk.
• Tannins. Found mainly in red wine, tannins can trigger headaches in tannin-sensitive people via serotonin pathways. This is why some people get headaches from red but not white.
• Biogenic amines. Histamine and tyramine, both produced during fermentation, are known migraine triggers in sensitive people. Histamine is higher in red wine. Some bodies metabolise these amines slowly.
• Dehydration. A glass of wine pulls roughly 100ml of water out of you. A bottle pulls a lot more. Most “wine headaches” are at least partly dehydration headaches.
• Sugar in cheap wine. Some inexpensive wines have hidden residual sugar to soften the taste. Sugar plus alcohol is a known headache combo.

If you suspect sulfites, try a simple test. Eat a handful of dried apricots and see what happens. If you don’t get a headache from that (and dried apricots have 5 to 10 times the sulfite content of wine), sulfites probably aren’t your trigger.

Why Does Dried Fruit Have More Sulfites Than Wine?

Because dried fruit needs heavy preservation to stay shelf-stable and keep its colour. Sulfites prevent the oxidation that turns dried apricots brown and apples grey.

Typical sulfite levels:

• Dried apricots: 1,000 to 3,000 ppm
• Dried apples and pears: 500 to 2,000 ppm
• Raisins and sultanas: 500 to 1,500 ppm (golden raisins are higher than dark)
• White wine: 80 to 150 ppm
• Red wine: 50 to 100 ppm

A small handful of golden raisins can deliver more sulfite than a full bottle of red wine. If sulfites were a major dietary problem for the general population, the dried fruit aisle would be a public health crisis. It isn’t.

What About “No Sulfite Added” or Natural Wine?

These wines exist, but the label doesn’t mean what most people think. (For the full taxonomy of organic, natural, and biodynamic, see organic vs natural vs biodynamic wine.) “No sulfite added” wine still has the 6 to 40 ppm of natural sulfites from fermentation. What’s missing is the controlled dose the winemaker would normally add at bottling.

The trade-off is real. Natural wines without added sulfites:

• Are less stable. They oxidise faster once opened, sometimes within a day.
• Have a shorter shelf life. Most are meant to be drunk young, often within a year or two of release.
• Are more vulnerable to bottle variation. Two bottles of the same wine can taste noticeably different.
• Sometimes carry funky, cidery, or barnyard notes that conventional wine drinkers don’t enjoy.

If you love natural wine, none of this is a problem. If you grabbed a “no added sulfites” bottle expecting a normal red and got something that tasted like sour kombucha, you’ve met the trade-off in person.

For people who genuinely have a sulfite sensitivity (the medically diagnosed kind), low-sulfite wine can be a meaningful improvement. For everyone else, it’s a stylistic preference, not a health upgrade.

Are Some Wines Naturally Lower in Sulfites?

Yes. Generally:

• Red wine has fewer added sulfites than white wine because the tannins and polyphenols in red provide built-in antioxidant protection.
• Dry wine has fewer than sweet wine because sweet wine’s residual sugar needs more SO2 to stay stable.
• Wine bottled at top producers tends to be at the lower end of the legal range because their fruit and process are clean enough to need less preservative help.
• Wines from cool climates and high-acid regions often need slightly less SO2 because acidity itself is mildly antimicrobial.

If you’re looking for lower-sulfite wines without going fully natural, dry red wine from a quality producer is generally your best bet. Look for wines from producers known for minimal intervention but with conventional bottling.

Should I Avoid Sulfites?

Probably not, unless you have a diagnosed sulfite sensitivity, severe asthma, or your doctor has told you to. For the vast majority of people, sulfites in wine are not the problem. The amount in a glass is small, your body metabolises it quickly, and the dried fruit in your kitchen has more.

If you do have asthma and react to wine, that’s worth taking seriously. Talk to your doctor, try lower-sulfite styles (dry red from a clean producer), and pay attention to whether dried fruit or processed potato products trigger you too. That’s a clearer signal than wine alone.

This isn’t medical advice. If you suspect a real sulfite allergy or sensitivity, see a doctor for proper testing. The practical advice in this article is for healthy adults trying to figure out what’s actually causing wine to disagree with them.

Frequently Asked Questions

Is “sulphites” different from “sulfites”?

No, they’re the same thing spelled differently. “Sulfites” is the American spelling, “sulphites” is the British and Commonwealth spelling. Same compound, same effect.

Will an organic wine have fewer sulfites?

Sometimes. EU-certified organic wine has lower sulfite caps than conventional wine (typically 100 ppm for red and 150 ppm for white, vs 150 and 200 conventionally). US organic rules are stricter still: a wine labelled “organic” in the US can have no added sulfites at all. So yes, organic wine usually has less, but it varies by region and certification. Our best organic wines round-up has bottle picks worth trying.

What about red wine specifically? Do reds have more sulfites than whites?

The opposite, usually. Red wine typically has less added sulfite than white because red’s natural tannins do some of the preservative work. The reason red wine causes more reactions in people isn’t sulfites, it’s tannins, histamine, and the higher alcohol that often comes with red.

Can sulfites cause hangovers?

The current evidence says no. Hangovers come from dehydration, congeners (other compounds in alcohol), poor sleep, and the alcohol itself. Sulfites haven’t been shown to drive hangover symptoms in non-asthmatic people. If wine hangovers feel worse than beer hangovers for you, the more likely culprit is the higher alcohol concentration and the speed at which wine goes down.

Are sulfite-free wines worth buying?

If you genuinely react to sulfites, yes. If you’re chasing a perceived “cleaner” wine without a real sensitivity, the upside is mostly philosophical. Natural wine is a beautiful category for its own reasons (fresh fruit, lower intervention, food-friendliness) but it’s a stylistic choice, not a guaranteed health win.

Does decanting reduce sulfites?

Slightly, yes. Exposing wine to air for an hour or two will let some SO2 dissipate. The reduction is small (10 to 20% in most cases) and probably below the threshold of perception for sulfite-sensitive people. Decanting is great for the wine’s flavour. As a sulfite reduction strategy, it’s marginal.

If you’ve been blaming sulfites for the wine that doesn’t agree with you, the next experiment is worth running: the same wine, well-hydrated, with food, on a night you didn’t sleep four hours. The headache might quietly disappear. For a softer, lower-tannin starting point, our best light red wines guide is full of bottles that go down easier than a big Cab.