In the last few years, you may have noticed two words appearing on the front of food packages in stores and in your own cupboard. “Gluten-Free,” they brag. That’s nice, but gluten is a substance found in wheat and some other cereal grains. Why do foods that never would have included wheat in the first place boast on their labels about their lack of gluten?

The answer is “both.” The reasons why people seek out gluten-free coffee and gluten-free canned fruit have to do with the facilities that our food comes from, and the reasons why people chose to avoid gluten in the first place.

Let’s start with what gluten is. Gluten is a protein present in wheat and other grains. You can separate gluten from wheat and create a meaty vegan dish called seitan, and it’s also added to some packaged foods to stabilize them. The main purpose of gluten on this planet is to make bread fluffy and delicious. When flour made from these grains is mixed with yeast and liquid, carbon dioxide bubbles form in the dough, and gluten forms the web of protein that traps the bubbles there.

There are several categories of people who seek out gluten-free food. Note that these categories are different from people who have an allergy to wheat or to grains: an allergy is a different sort of reaction that can be instantly fatal and involves the immune system.

People with celiac disease. The prevalence of this disease varies by country and even by ethnicity, but current estimates are that about 3 million people in the United States have it. People who have celiac disease have strong digestive distress when they eat food containing gluten, and can even react to trace amounts. When they eat gluten, their immune systems turn on their bodies but only attacks the lining of the small intestine. Celiac disease is diagnosed through various methods, including blood and genetic tests, and a biopsy of the small intestine to confirm that diagnosis.

People who are sensitive to gluten. They have digestive trouble or other problems when they eat food containing gluten, but they don’t meet the diagnostic criteria for celiac disease. This is a controversial category, even among gastroenterologists. It’s possible that people who are gluten-sensitive and feel better after eliminating grains from their diet are actually sensitive to carbohydrates called fermantable oligo-saccharides, di-saccharides, mono-saccharides and polyols, or FODMAPs. Wheat contains FODMAPs, but so do other foods like cow’s milk, onions, and blueberries. Unfortunately, food labels that say “FODMAP-free” are not yet popular.

People who think that eliminating gluten from their diets has mystical weight loss powers. Yes, we all know at least one person like this, and while their existence does hurt the reputation of gluten-avoiders, they help create more demand for gluten-free foods. Some people also might try out a gluten-free diet while trying to narrow down the cause of their illness.

While diagnosis of celiac disease and of gluten sensitivity has been increasing, the disease wasn’t invented just in the last few years. Yet until 2013, there were no set rules for how much gluten a food could contain before manufacturers could slap a “Gluten-free” label on it. If people with celiac disease couldn’t rely on product labeling, why bother?

The FDA’s regulations went into effect in 2014 and define terms like “gluten-free” as well as other ways that manufacturers might phrase it, such as “no gluten,” “free of gluten,” or “without gluten.” To get this label, a food item must have fewer than 20 parts per million of gluten present. While they might contain exactly zero molecules of gluten, that’s the lowest amount that current methods are able to detect.

People who don’t want to eat gluten can just go to the store and buy stuff that doesn’t have wheat in it, then, right? It’s too bad that they can’t eat a nice loaf of bread or order a pizza, but why does everything need “Gluten-Free” plastered on it?

Sometimes a gluten-free label is extra reassurance, such as for distilled spirits, which theoretically should contain no gluten or other proteins at all. There isn’t any good reason why a container of mashed potatoes, for example, would contain gluten.

Yet gluten and its derivatives are used as food additives and stabilizers. Making everything from scratch isn’t necessarily a protection from gluten, either: it’s possible for whole ingredients like oats and even fruit and vegetables to have some gluten. When our food is processed and packaged in places that also processes food made from gluten-containing grains. Cross-contamination is when a potential allergen that was processed on the same equipment or in a neighboring part of the factory contaminates a product that’s supposed to be free of that allergen.

The FDA “gluten-free” label sets the threshold for how much gluten a product can contain very low, as low as current testing methods are able to detect. It means there’s a consistent rule for what “gluten-free” means, which in turn has made the label more common.

Normally, you’d assume that ingredients like cabbage, mustard, and vinegar would be gluten-free. Not so fast, person who eats food and makes assumptions! A condiment-maker explained to Consumerist that what seems straightforward enough may not be, and adding something as simple as mustard powder can add gluten.

“While mustard seeds are gluten-free, some commercial brands of mustard use a mustard powder that contains wheat,” explains Julie Busha, creator of Slawsa, a spicy cabbage-based condiment that has the words “Gluten-Free” on the label. The average person might not know this, but the savvy person on a gluten-free diet and food manufacturers would. “Those who are highly sensitive to gluten really need to watch which mustard is being used.”

That would make it important to label food like salad dressings and marinades that might contain gluten or wheat derivatives as gluten-free, too.

Or even snack foods that one would think are inherently gluten-free.

Sometimes a food manufacturer decides not to explicitly label their products as gluten-free, but markets them explicitly to the gluten-free community anyway. That’s the case for Barnie’s Coffee Kitchen, which sells coffee concentrate packets that can be used to make instant hot or iced coffee that is gluten-free. The company doesn’t label their products yet, but does plan to label them as gluten and allergen-free in the future. Instead, they’ve been reaching out at events for consumers who avoid gluten or other allergens.

“Based on consumer research we have recently conducted, we discovered there is confusion about coffee being gluten and allergen free,” Sonja Hardy, SVP of Marketing and Strategic Brand Relations explained. “Some other coffee companies do have additives in their coffee products, so many consumers are wary.”

In the end, this is about the health and comfort of the people who have to avoid gluten. It’s really easy to laugh at a box of gluten-free cereal that’s made from rice, but a lot less funny if that product were cross-contaminated and made someone you care about sick. People with celiac disease who don’t avoid gluten don’t just have to deal with tummy aches: they risk malnutrition if they eat gluten, and even a higher risk of some gastrointestinal cancers.

Having the label simplifies shopping for people new to gluten avoidance, and for people who have to cook for them without having a deep knowledge of food sources and cross-contamination risk. “Those just starting out or those
wishing to purchase products for gluten-free family and friends would find the info helpful,” one gluten-free reader explained to Consumerist over e-mail.

“No matter how obvious it seems to some of us, [some people are] still
going to question whether or not the banana they’re eating has gluten or
not,” gluten-free living expert Danna Korn points out.

That’s what it should be about, isn’t it? Simplifying food labels in this way means not causing physical pain and potential long-term health consequences for friends, relatives, and other guests who might follow a gluten-free diet.

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