A glass of wine can relieve stress and enhance the flavor of your meal. But this ancient beverage isn't perfect. Wine contains sugar, might leave you dehydrated, and doesn't always fit into a restrictive diet. Which leaves us wondering: are both red and white wines gluten-free?
Generally speaking, yes, but “it’s not so straightforward,” New York City nutritionist Keri Gans, RD, tells Health.
First, a gluten refresher: Gluten is a type of protein found in wheat and other grains, such as barley and rye. Some people have a sensitivity to gluten or are gluten intolerant, meaning that when they consume foods containing gluten, they develop symptoms like abdominal discomfort or joint pain. Gluten is also problematic for the 1% of the population that has celiac disease, an autoimmune disorder in which gluten attacks the small intestine and can cause painful symptoms like bloating, fatigue, and weight loss.
Gans explains that red and white wines are made predominantly from grapes. Grapes are gluten-free, and the fermentation process also involves no gluten. Yet there are ways that gluten can get into a bottle.
When wine is made, wine producers use a process called fining. During this process, fining agents bind with unwanted particles and debris in wine, which can then be filtered out so the wine appears more clear. But if a wine maker uses gluten or a product containing gluten as a fining agent, the gluten can remain behind and stay in the bottle of wine. For someone with a gluten allergy or sensitivity, this could potentially be harmful.
But don't throw out that bottle just yet: a study from The Journal of Agriculture and Food Chemistry suggests that gluten from fining is less than 20 parts per million (ppm) or 0.002% of the product—which is the maximum amount of gluten a product can have and still be labeled gluten-free, based on guidelines set by the Food and Drug Administration.
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"Most gluten-intolerant people would be unaffected by the tiny level of gluten leftover from fining," Gans says. "However, there are some people that might have celiac [disease] and are extremely sensitive to any level of gluten, and for those people, it would be best to be very careful before trying a new wine."
But it's not always easy to know how much gluten wine contains. The US Alcohol and Tobacco Trade Bureau doesn’t require wine manufacturers to list ingredients, and many other countries don’t require them, either. Gans says you have to do your homework to find out if the glass of wine you’re about to toss back is gluten-free or not.
“If there’s a wine you’re interested in, contact the company or grower,” advises Gans. “They’ll be able to tell you whether or not any gluten-containing products made their way into the process."
If you're planning on whipping up a batch of your own homemade vino, you can make sure no gluten gets into the wine production process. Otherwise, if you're on a gluten-free diet, check any wine you plan to imbibe to make sure you won't accidentally sip some gluten.
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