How can you tell if something is gluten-free on the box?

October 24, 2025 •

3 min read

According to the U.S. Food and Drug Administration (FDA), any product with a “gluten-free” claim must contain less than 20 parts per million (ppm) of gluten. Understanding how can you tell if something is gluten-free on the box is essential for individuals managing celiac disease or gluten sensitivity. This requires paying close attention to both explicit claims and the ingredient list to ensure a product is safe.

Quick Summary

This guide explains how to identify gluten-free products by distinguishing between regulated claims and third-party certifications. It details how to scrutinize ingredient lists for hidden gluten sources, understand cross-contamination warnings, and confidently make informed choices.

Key Points

Look for Regulated Claims: Always check for the term 'Gluten-Free' on the packaging, which indicates the product contains less than 20 ppm of gluten as per FDA rules.
Identify Certification Seals: For stricter assurance, seek out third-party certification logos like GFCO (typically <10 ppm) or the Crossed Grain symbol, which involve regular audits.
Scan the Ingredient List: Even with a gluten-free claim, scan the ingredients for wheat, barley, and rye, which must be clearly labeled if used intentionally.
Beware of Hidden Gluten: Be cautious of ingredients like malt, modified food starch, and certain flavors that can contain gluten if not sourced from a gluten-free ingredient.
Interpret Advisory Warnings: Understand that 'May contain' warnings indicate a risk of cross-contamination. A certified gluten-free product with this label should still be safe, but those with high sensitivity may choose to be extra cautious.
Be Vigilant with Oats: Always choose oats and oat products that are specifically labeled 'Gluten-Free' to avoid cross-contamination with wheat.

Understanding Gluten-Free Claims

The most straightforward way to identify a gluten-free product is to look for the claim on the packaging. However, not all gluten-free labels are created equal. You must understand the difference between a manufacturer's self-declared claim and a third-party certification mark.

FDA-Regulated “Gluten-Free” Claims

In the United States, a food manufacturer can voluntarily label a product as “gluten-free,” “no gluten,” or “without gluten” if it meets the federal standard of containing less than 20 ppm of gluten. This explicit claim is regulated by the FDA. The FDA standard, however, doesn't apply to non-packaged foods like those in restaurants.

Third-Party Certifications

Many manufacturers opt for third-party certification for added consumer assurance. These organizations often have stricter standards and conduct regular testing.

GFCO Certified: Products with the Gluten-Free Certification Organization (GFCO) logo must test below 10 ppm of gluten, stricter than the FDA's limit. The current logo has a curly lower-case "g" within a circle.
Crossed Grain Symbol: Common in Europe, this symbol indicates compliance with strict gluten-free standards.
Celiac Support Association (CSA): This program aims for no detectable gluten in the final product.

Decoding the Ingredient List

If a product lacks a gluten-free claim, carefully read the ingredient list. While allergens like wheat are often emphasized by law, other gluten sources like barley and rye may not be.

Key Gluten-Containing Grains and Derivatives to Avoid

Wheat: Includes various species and derivatives like flour, starch (unless gluten-free), and hydrolyzed wheat protein.
Barley: Look out for malt extract, flavor, syrup, vinegar, and brewer’s yeast.
Rye: Found in items like rye flour and bread.
Triticale: A wheat-rye hybrid.
Oats: Choose only oats specifically labeled “gluten-free” due to common cross-contamination.

Watch Out for Hidden Gluten

Gluten can be present in unexpected ingredients:

Modified Food Starch: May be derived from wheat; confirm the source or look for a gluten-free claim.
Dextrin: Can sometimes be wheat-based.
Yeast Extract / Natural Flavors: May contain barley; contact the manufacturer if no gluten-free claim is present.
Soy Sauce: Traditional soy sauce contains wheat; opt for gluten-free versions or tamari.
Processed Meats: Fillers or marinades in some deli meats, hot dogs, and sausages may contain gluten.

Understanding Cross-Contamination Warnings

Advisory statements like “May contain wheat” indicate a risk of cross-contamination. If a product is labeled gluten-free, the claim takes precedence as the manufacturer has measures to keep gluten below the limit. However, for those with severe sensitivity, a certified product might be preferable.

FDA vs. Certified Gluten-Free: A Comparison


Aspect	FDA Gluten-Free Labeling	Third-Party Certification
Gluten Limit	Less than 20 ppm	Often stricter, e.g., GFCO (<10 ppm) or CSA (no detectable gluten)
Oversight	Manufacturers self-regulate; FDA investigates based on complaints	Independent third-party organizations conduct regular testing and audits
Verification	Manufacturer-provided assurance	Independent verification and stricter protocols
Visual Indicator	Simple text like "Gluten-Free" on packaging	Specific seals or logos, such as GFCO or the Crossed Grain symbol
Cost	No additional certification fees for manufacturers	Requires annual fees for manufacturers to maintain certification

Conclusion

Identifying gluten-free products involves understanding both government regulations and third-party certifications. While an explicit “gluten-free” claim is a good indicator, a reputable third-party certification seal offers added confidence, particularly for those with celiac disease. By recognizing different labels and being aware of hidden ingredients, you can make safe dietary choices.

Frequently Asked Questions

A "gluten-free" claim is self-regulated by the manufacturer under government rules (e.g., less than 20 ppm gluten for the FDA). A "certified gluten-free" product has been independently verified by a third-party organization, which often has stricter standards and requires regular audits and testing.

No, a "wheat-free" label does not guarantee a product is gluten-free. The product could still contain gluten from other grains like barley or rye. You must check the full ingredient list for all potential gluten sources.

For most individuals with gluten sensitivity, a product with both labels is safe to consume. The "gluten-free" claim indicates the final product has been tested to meet the legal limit of less than 20 ppm. The advisory warning simply notes potential cross-contact risks, which the manufacturer's processes are designed to mitigate.

Hidden gluten can appear under names like malt (from barley), brewer's yeast, certain flavorings, and modified food starch. Unless the product is labeled gluten-free, scrutinize these ingredients or contact the manufacturer to confirm their source.

No, regulations vary globally, though many countries follow standards similar to the FDA's (<20 ppm) or European Union's. Third-party certifications like the Crossed Grain symbol or GFCO help ensure products meet consistent international standards.

Naturally gluten-free foods can be contaminated during processing if they are handled in a facility that also processes wheat. For grains like oats, it is best to only consume those explicitly labeled “gluten-free” to avoid cross-contamination.

The 20 ppm standard is based on research suggesting it is a safe level for most individuals with celiac disease, as it is the lowest amount that can be reliably detected with validated scientific testing methods.