Organic food has a reputation for being healthier than conventional, and there’s some evidence for that. But when it comes to organic wine, the health benefits are much less clear, experts say. And they won’t help you avoid a hangover.
Organic wines still make up just a tiny fraction of the U.S. wine market, but when they are sold here, they must be approved by the USDA, just like fruits and vegetables. The USDA has three levels of organic certification that can appear on wine bottles: “100% organic,” “organic” and “made with organic grapes.” Each of these have standards for the amount of organic ingredients that must be in the wine (100% organic ingredients, at least 95% and at least 70%, respectively). There are also other categories—like “biodynamic,” which has its own private regulatory bodies and treats the whole vineyard as a living ecosystem, even taking into account astrological influences.
But the main difference between all these categories, according to wine experts, is the amount of sulfites.
Sulfites—preservatives added to wine to prevent it from spoiling, oxidizing and aging too quickly—are perhaps the most controversial ingredients in the wine world. They have long been a key feature of winemaking, because yeast naturally produces low levels of them during fermentation. Organic and 100% organic wine must have no added sulfites and can only contain them up to 10 parts per million (ppm). Wine made with organic grapes and biodynamic wine can have sulfites up to 100 ppm, and conventional processed wine can have sulfites up to 350 ppm.
So the fewer sulfites, the better—right? Not necessarily. Without sulfites, it’s difficult to make wine that smells, looks or tastes like what most shoppers are used to drinking, says Ryan Elias, a food chemist at Penn State University. A very small percentage of people are allergic to sulfites, which is why winemakers must list them on their labels. But unlike food packages, wine bottles are not required to list many other ingredients, which can make sulfites stand out. “On a wine bottle there’s a disclosure that says ‘contains sulfites,’” Elias says. “That concerns a lot of consumers, because they think if there’s disclosure on the label, it must be something bad.”
While people often blame sulfites for causing hangovers, experts say evidence does not support this. Some studies have shown that sulfites can cause asthmatic reactions in a small number of people, but when it comes to avoiding a pounding headache, research suggests that other wine components like histamines and tannins—or even alcohol itself—are more likely to be involved.
In fact, most people are already used to sulfites. Amino acids in the human body naturally produce them as part of their efforts to break down alcohol toxins. Sulfites are also used in plenty of other foods; they keep dried fruit from browning. “If you can eat dried apricots and not get a headache, then you can you drink wine and not get a headache because of sulfites,” Elias says. “You’re getting a headache from something else.”
Beyond sulfites, winemakers can use many other additives to change the finished product—some even with an organic certification. Additives can range from “Mega Purple,” a grape concentrate used for color and sweetness, to oak chips for flavor, to animal products such as gelatin, egg whites, milk products, fish bladders and even clays like bentonite, for fining and clarifying the wine. As long as these ingredients are made organically or don’t contain anything banned on the national list of allowed and prohibited substances, they can be used when making organic wine.
Some advocates are pushing for more ingredient labeling on wine bottles, but that’s still pretty far off in the future, says Magali Delmas, an environmental economist at UCLA’s Institute of the Environment and Sustainability. And because wine is treated as a luxury in the U.S., there is very limited research into potential health effects of organic wine, which Delmas says leaves customers to make a lot of assumptions. “Eco-labels are supposed to reduce the information asymmetry,” says Delmas. “But right now you need to be in the know to appreciate the [organic] certification.”
Some may choose organic wine to sidestep pesticides—another big issue when it comes to growing wine grapes. However, while some chemicals are banned from use in organic wines, others are still allowed, and wine labels don’t have to include them.
Seeking out information about growers’ pesticide and farming practices is the best thing consumers can do if they want to drink healthier wine, says Amanda Stewart, assistant professor of food science and technology at Virginia Tech. Some regions have local certification programs that guide winemakers in sustainable practices tailored to the climates they’re working in, and vineyards often offer more information about their processes to customers who visit.
“It’s not as simple as having a program like organic, where they say you can do all these things and it’s applied all over the country,” Stewart says. “I’d rather somebody look at the whole picture than just go to the grocery store and say ‘okay, this wine was made without sulfites.’”
This story originally appeared on Time.com.