Sulfite Myths

"Contains Sulfites." These are words you see on almost every bottle of wine. Just two words, yet so misunderstood! What are sulfites? Are they really bad? Are they the cause of wine headaches? Recently, I presented a tasting where the most prevalent statement was “I get headaches from the sulfites in red wine.”  Is that true?

What Are Sulfites?

The term ‘sulfite’ is a term for sulfur dioxide (SO2).  SO2 is a preservative and widely used in wine making and most commercial foods, because it’s antioxidant and antibacterial. SO2 plays an important role in preventing oxidization and maintaining a wine’s freshness.

Are Sulfites Harmful?

Sulfites are generally harmless, unless you suffer from severe asthma or don’t have the particular enzymes necessary to break down sulfites in your body. There are people who have a genuine allergy to sulfites, and these allergies are often linked with asthma. The FDA says that less than 1% of the US population is sulfite sensitive, so it's relatively rare. If you do have a sulfite allergy it’s more likely to reveal itself through a food other than wine, since many foods have higher levels of sulfites than wine.

How Much Sulfite is in Wine?

The level of sulfites that a wine can contain is highly regulated around the world. Any wine containing more than 10 parts per million (ppm) of sulfur dioxide must state on the label ‘contains sulfites’.

Myths About Sulfites in Wine

Myth #1: Sulfites in wine cause headaches.

Medical research isn’t definitive on the relationship between sulfites and headaches. There are many other compounds in wine such as histamines and tannins that are more likely connected to the headache effect (not to mention alcohol!).

Myth #2: Red wine has extra sulfites, thus causes headaches.

In the EU the maximum levels of sulfur dioxide that a wine can contain are 210 ppm for white wine, 400 ppm for sweet wines and 160 ppm for red wine. The fact that red wines typically have a lower sulfite level may seem surprising to people who blame sulfites for their red wine headaches! Very similar levels apply in the U.S., Australia and around the world.

Red wines have a lower level of sulfites because they contain tannin, which is a stabilizing agent, and also almost all red wines go through malolactic fermentation. Therefore, less sulfur dioxide is needed to protect the wine during wine making and maturation.

Myth #3: Wine should be avoided because it contains sulfites.

Another surprising fact is that wine sulfite levels are about ten times less than most dried fruits, which can have levels up to 1000 ppm. So if you regularly eat dried fruit and don’t have any adverse reaction you’re probably not allergic to sulfites. While these figures are maximum SO2 levels, in practice, sulfite levels are generally well below the maximum permitted limits.

Myth #4: Sulfites are inherently unnatural.

Other than the potential allergic reaction, many people are against sulfites because they feel they’re an unnatural addition when making wine. It’s important to remember that sulfites are a natural byproduct of yeast during fermentation. So even if you don’t add any additional SO2, your wine will still contain sulfites.

A better understanding of how sulfur dioxide breaks down and binds during wine making, better winery hygiene and more careful practices to ensure healthy grapes (i.e. no rot) have all helped to reduce the need for SO2 additions during wine making. Today, there are many winemakers who refrain from adding any SO2 until after the fermentation is complete.

Why Sulfites Are Necessary in Wine

There are really very few wines that are made without some use of SO2. This is because wine is perishable, prone to oxidation and the development of off odors. SO2, particularly for white wines, is important for freshness. Wines without any SO2 generally have a shorter shelf life, about six months, and need to be kept in perfect storage conditions. Since a winemaker has very little control over the wine’s storage conditions from the time the wine leaves the winery until it is consumed, it’s no wonder that SO2 is so widely used to help guarantee that the bottle of wine you open will be fresh and clean, and taste as the winemaker intended. Additionally, one of the reasons that you see more wines labeled ‘made from organically grown grapes’ than labeled ‘organic wine’ is because in the US organic wine must not have any added SO2.

We are beginning to see a number of "natural" wines on the market, where little or no SO2 is added. This is a great development for the small part of the population that has an allergy to sulfites. Omitting sulfites is easier with red wines, because the tannin acts as a as a natural antioxidant. It also helps if natural wines are sold locally and not shipped. This local aspect of "natural" wines is part of what makes them so interesting; they're often best discovered close to their place of origin.

So Why Do I Get a Headache When I Drink Red Wine?

All of these scientific facts, however, do nothing more than say that sulfites are probably not the culprit for the phenomenon of red wine headaches. Possible reasons include histamines, and the alcohol content itself.  Drink up!