How to Read a Food Allergy Warning Label Labels on foods containing the main causes of allergic reactions – milk, peanuts, shellfish – have made supermarket aisles safer for the 12 millions of Americans with food allergies. But labels still contain potential pitfalls. Here, tips for what to watch out for.
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How to Read a Food Allergy Warning Label

The label on a tub of Land O Lakes butter lists milk as an ingredient that may cause an allergic reactions. Scott Olsen/Getty Images hide caption

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Scott Olsen/Getty Images

A food with a "gluten-free" label may not be gluten free at all. Such products may contain trace amounts of the wheat protein — enough to trigger a reaction in some people. The FDA is currently considering an industry-wide standard definition for "gluten-free."

Meanwhile, the agency has already taken a huge step in easing a health risk for the increasing number of Americans with food allergies: mandatory food labeling.

As of January 2006, all food products must clearly say on the package if they contain any of the foods that are responsible for most allergies: milk, tree nuts, peanuts, soy, wheat, egg, crustacean shellfish or fish.

"Before this labeling act went into effect, there were 20 different ways that milk could appear on a label," says Anne Munoz-Furlong, founder of the Food Allergy & Anaphylaxis Network. "That made it impossible to teach a 7-year-old to look at a label and to know what to avoid. Now, words are in simple language, and you don't need a science dictionary when you go to the grocery store."

For instance, if an ingredient contains casein, which is a milk protein, the label must include the words "contains milk," or the ingredients list must include "milk." Ditto for "egg" if a product contains albumin, and "soy" if it contains miso.

The estimated 12 million adults and children with food allergies aren't completely in the clear in supermarket aisles. People with food allergies can't predict the scale of an allergic reaction, but carefully reading food labels is the equivalent of wearing a seat belt, says Elizabeth Matsui, a pediatric allergist at the Johns Hopkins Children's Center.

Labeling pitfalls to keep an eye on:

Read the Product Label – Every Time: A product's ingredient list might have been free of a specific allergen the last time you bought it, but manufacturers can change ingredients without warning.

Dairy Free: "Free" labels, such as "peanut free" and "gluten free," aren't regulated by the FDA. "Dairy free" can be particularly tricky. On the front, a product may say "dairy free," but on the back, casein/milk may be listed under ingredients. Examples of food advertised as "dairy free" that may contain milk: coffee whiteners, whipped toppings, imitation cheeses and some soft-serve ice creams.

May Contain: This unregulated label is a sore spot with some food allergy experts and advocacy groups. "May contain" labels are a safety net for what's called unintentional "cross-contamination" of a food product. That is, a chocolate bar may not be made with peanuts, but it may have been contaminated with a trace amount of peanut because it was produced on the same manufacturing line as a peanut candy bar.

"The truth of the matter is that nobody really knows what that label means," says Elizabeth Matsui, a pediatric allergist at the Johns Hopkins Children's Center. "The 'may contain' labeling could mean anything from there's no allergen in that food to there is actually a great deal of allergen from cross-contamination."

And groups that might not spend a lot of time considering risk — teens, for instance — are likely to disregard the labels, says Munoz-Furlong.

"Teens who have survived reactions, they're telling us they ignored the 'may contain' label because it's on so many things, and they don't believe the label. We need to make these labels believable."