"Oh, I can't drink red wine because of the sulfites, they give me a headache."
I often hear this statement at wine tastings and it represents one of the most commonly held misconceptions about "Red Wine Headache," a malady that affects many wine lovers. If you suffer from this affliction, there's some potentially surprising science behind the cause of these headaches as well as strategies you can employ to keep it from happening again in the future.
First, a little on sulfites: sulfur dioxide, or SO2, is the form of sulfur that's most relevant to winemaking. This chemical is actually more important for the preservation of white wine which has lower levels of natural preservatives than red wine. The primary function of sulfur dioxide is as a preservative and disinfectant yet it also inhibits bacteria and yeast as well. Sulfur dioxide preserves wine by reacting with oxygen, a well-known enemy of wine, to prevent oxidation which can adversely affect a wine's color and flavor. For this reason, it is also used, at much higher amounts than are found in wine, in many fruit juices and dried fruits to keep them from spoiling and turning brown.Tannins are chemical compounds which have important preservative properties which are derived primarily from grape skins and to a lesser extent from oak barrels. Red wine spends more time in contact with the grape skins and oak than white wine so it inherently contains more of these compounds. In the absence of tannins, higher levels of sulfites must be added to white wines to prevent spoilage. While it may come as a surprise that white wine contains more sulfites than red, sweet white wines generally contain even more sulfites than dry white wine! Higher levels of sulfites are needed in the sweeter wines to prevent any strains of wild yeast from inducing another fermentation because of the higher sugar content. So to sum it up, wines which contain the most sulfites in order of most to least are:1. Sweet White Wines (Sauternes, Juracon, etc)2. Dry White Wines (Sauvignon Blanc, Chardonnay, etc)3. Dry Red Wines (Cabernet Sauvignon, Pinot Noir, etc)The bottom line is, if you're experiencing headaches after consuming only red wine, sulfites are most likely not the culprit. Additionally, the most common reactions to sulfites are breathing-related problems (especially in asthmatics); sulfites are generally not known to cause headaches.So if it's not sulfites causing "Red Wine Headache" then what is it, you ask? Well the jury's still out on that one and, to date, there's no research that definitively answers that question. There are so many compounds in red wine (more than in white), it is difficult to pin the blame on just one. Some prime suspects, however, are the tyramines and histamines produced during malolactic fermentation which are present at much higher levels in red wine. These compounds are not unique to wine and are also present in food products that have been aged or fermented including cured meats, aged cheeses and soy.There are a few hypotheses as to why these chemicals can trigger these terrible headaches. One relates to the increase in serotonin levels caused by tyramines to which some individuals can be very sensitive. Just the mere fluctuation of these levels is enough to bring on a headache. Another explanation involves tyramines' ability to cause dilation and contraction of blood vessels which can also trigger a migraine. One researcher concluded that tyramines can actually induce headaches in up to 40% of migraine sufferers. Of course with all wine, white or red, there's the complicating factors of quantity of consumption and alcohol content which seem to exacerbate any existing sensitivity to the aforementioned chemical compounds making it even more difficult to identify the source.While there's no definitive answer as to the cause of "Red Wine Headache," there are some strategies you can employ to hopefully decrease your chance of experiencing it in the future. If you find yourself experiencing headaches after drinking red wine only it's probably best to stick to reds with lower levels of tannin and alcohol such as Pinot Noir and Gamay. Or, you might even embrace white wine more frequently which may reduce the incidence as well. Since we all have or own unique body chemistry it's best to learn through trial and error and let your body be your guide. Hopefully you can find a way to still enjoy the red wine you love while not having to suffer for it!Cheers,