A wine-drinking friend of mine used to insist that any headache after wine was from the sulfites. I’d heard this so often I started to believe it, until I looked into it and realized the science really doesn’t support the claim. If sulfites were causing wine headaches at the concentrations found in wine, dried apricots — which contain far more sulfites per serving — would be a public health crisis. They’re not. The sulfite-headache connection is one of those things that got repeated until it became accepted fact without ever being particularly well-supported.
What Sulfites Actually Are
Sulfites is the umbrella term for compounds containing sulfur dioxide (SO2). They occur naturally in wine as a byproduct of fermentation — yeast produces small amounts of sulfur dioxide as it converts sugar to alcohol. This is why no wine is truly sulfite-free, even wines labeled “no sulfites added.” A wine made with zero added SO2 will still have some naturally occurring sulfites from fermentation, typically in the range of 10–20 parts per million (ppm).
Winemakers have been adding sulfur dioxide intentionally since at least Roman times. The Romans would burn sulfur inside amphorae before filling them with wine, which is essentially the same principle as adding SO2 today. It works as both an antimicrobial agent and an antioxidant, and those two functions are critical to producing stable wine.
Why Winemakers Use Sulfites
The antimicrobial function: sulfites inhibit the growth of unwanted bacteria and wild yeasts that would otherwise compete with the cultivated wine yeast or cause the wine to spoil after fermentation. Without some level of SO2 protection, a bottle of wine traveling to a retailer, sitting in a warehouse, and then aging in someone’s cellar would be far more likely to turn into vinegar or develop off-flavors from bacterial activity.
The antioxidant function: oxygen is the enemy of wine stability. Even small amounts of oxygen exposure can strip freshness from white wines and cause premature browning. Sulfites mop up free oxygen molecules, protecting the wine’s color and fresh aromas. This matters more for white wines and delicate reds, which is why these categories tend to have higher sulfite levels than robust tannic reds. Red wines have their own antioxidants from the grape skins — tannins and polyphenols — which provide some natural protection.
How Much Is Actually In There
Typical sulfite levels by wine type give a useful sense of scale:
Red wines generally run 50–100 ppm. White wines tend toward 100–200 ppm. Sweet wines are often above 200 ppm because sweetness encourages microbial growth, so more protection is needed. The legal limit in the United States is 350 ppm. The EU limit is similar. Any wine above 10 ppm in the US must carry a “contains sulfites” label, which is why it’s on almost every bottle.
For comparison, dried apricots can contain 1,000–3,000 ppm of sulfites. Grape juice, pickles, lunch meats, and some condiments all contain sulfites. People who react severely to sulfites — a genuinely rare sensitivity, most common in people with asthma — would experience problems across a wide range of foods, not just wine.
What Actually Causes Wine Headaches
The honest answer is that it’s complicated and probably varies by person. Alcohol itself is a vasodilator and a dehydrating agent, both of which contribute to headaches. Histamines in red wine, produced during fermentation, affect some people. Tannins may be a factor for others. Drinking wine on an empty stomach, not drinking water alongside it, or simply drinking more than your body can process efficiently — all of these are better-supported explanations than sulfites for most people’s wine headaches.
The “Natural” and Low-Sulfite Wine Movement
There’s a growing market for natural wines made with minimal or no added sulfites. These wines can be genuinely interesting — the lack of SO2 means the winemaker is essentially working without a safety net, relying on scrupulously clean winemaking and extremely precise harvest timing. Some of these wines are excellent.
They’re also less stable. Natural wines are more susceptible to temperature fluctuations, shipping damage, and variation from bottle to bottle. That’s a real trade-off, not just a marketing caveat. Organic wines, while often using reduced sulfite additions, still typically add some SO2. Biodynamic wines follow similar principles.
Ascorbic acid (Vitamin C) is sometimes used as a co-preservative with sulfites, or occasionally as an alternative, but it doesn’t have the same antimicrobial properties and isn’t a complete substitute.
Practical Guidance
If you’re sensitive to wine and want to minimize sulfites, red wines are generally your best bet for lower total SO2. Dry wines of all types have lower sulfites than sweet wines. If you have documented sulfite sensitivity (usually accompanied by asthma symptoms, hives, or respiratory issues), consult a doctor — and recognize that your reaction to wine may be from something other than the sulfites in the first place.
For everyone else, sulfites at wine concentration levels aren’t a health concern. They’re doing useful work in the bottle, the wine world has relied on them for thousands of years, and the worry about them is mostly disproportionate to any actual risk.
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