Which teas contain gluten? A Guide to Gluten-Free Sipping

January 13, 2026 •

4 min read

According to the National Celiac Association, pure teas from the Camellia sinensis plant are naturally gluten-free. However, the growing popularity of blended, flavored, and herbal infusions means that not all teas are gluten-free, with many containing gluten-based additives or facing cross-contamination issues.

Quick Summary

Pure teas are often gluten-free, but specialized blends, certain herbal varieties, and flavored options frequently contain hidden gluten ingredients like barley malt. Cross-contamination during processing also poses a risk. Always check labels or choose certified gluten-free products to ensure safety.

Key Points

Pure Tea is Gluten-Free: Teas from the Camellia sinensis plant (black, green, white, oolong) are naturally gluten-free unless additives are used.
Watch for Barley: Teas containing roasted barley (Mugicha, Boricha) or barley malt extract are not gluten-free and should be avoided.
Hidden Ingredients in Blends: Flavored and herbal teas can contain gluten ingredients or natural flavorings derived from gluten-containing sources.
Cross-Contamination is a Risk: Even pure teas can be contaminated if processed on the same equipment as gluten products.
Look for Certification: A third-party gluten-free certification mark (like GFCO) ensures the product meets strict safety standards.
Loose-Leaf is Often Safer: To minimize risks from additives and tea bag glues, consider choosing loose-leaf tea over bagged options.

Understanding the Basics: Pure Tea vs. Blends

The key distinction lies between pure tea and processed or blended varieties. Pure teas come from the Camellia sinensis plant, the source of black, green, white, and oolong tea. These leaves are naturally gluten-free. Risk is introduced when other ingredients are added, or when manufacturing practices allow for cross-contamination.

The Common Culprits: Teas Containing Gluten

Certain teas are more likely to contain gluten. Recognizing these can help you avoid potential health issues. The most common gluten-containing tea is made directly from a gluten-rich grain.

Barley Tea (Mugicha): Popular in Japan and other parts of East Asia, this beverage is brewed from roasted barley, a grain that contains gluten. In Korea, a similar barley tea called Boricha is also brewed and contains gluten.
Malted Teas: Some tea blends use barley malt extract as a flavoring or sweetener. The presence of "malt" in the ingredients list is a strong indicator of a gluten-containing product. This can appear in dessert-themed or seasonal tea blends.
Teas with Grain Additives: Certain specialty or herbal teas might include roasted barley, wheat grass, or oat straw for flavor or health benefits. While oats are naturally gluten-free, they are often processed on shared equipment and are high-risk for contamination.

Hidden Sources of Gluten in Tea

The most concerning sources of gluten are often hidden, found in additives or resulting from manufacturing processes.

Flavorings: "Natural flavors" can be a vague term hiding gluten-based ingredients. If the source is not specified, it is wise to contact the manufacturer to inquire about the flavoring's origin.
Tea Bags and Packaging: Less common but still a risk, some manufacturers use wheat-based glues to seal tea bags to the string. For those highly sensitive to gluten, loose-leaf tea might be a safer option, though this practice is becoming less frequent.
Cross-Contamination: This is arguably the biggest hidden danger. If a company processes both gluten-free and gluten-containing ingredients on the same equipment, trace amounts can find their way into the gluten-free products. Studies have even found undeclared gluten in products like green tea and flavored herbal tea.

Comparison: Gluten-Free vs. Gluten-Risk Teas


Feature	Naturally Gluten-Free Teas	Gluten-Risk Teas
Origin	Derived exclusively from the Camellia sinensis plant.	Include added ingredients, flavorings, or are made from grains.
Types	Black tea, green tea, white tea, oolong tea.	Mugicha (barley tea), Boricha, malted teas, many herbal and flavored blends.
Ingredient List	Contains only pure tea leaves, with no other additives listed.	May list "natural flavors," malt, or specific grains like barley or wheatgrass.
Certification	Often certified gluten-free to ensure no cross-contamination.	Rarely certified due to the presence of gluten-containing ingredients.
Risk of CC	Low risk, but can still occur if processed on shared equipment.	High risk due to shared manufacturing lines.
Preparation	Steeped loose-leaf is the safest option.	Should be avoided by those with celiac disease or high sensitivity.

How to Ensure Your Tea is Gluten-Free

Look for Certification Labels

The most reliable way to guarantee a tea is gluten-free is to look for a third-party certification label, such as the Gluten-Free Certification Organization (GFCO) mark. This means the product has been tested to meet strict standards and is verified to contain less than 10 or 20 parts per million of gluten, depending on the country. Companies like The Republic of Tea are known for carrying these certifications.

Read the Ingredients List Carefully

Always examine the ingredients list. While wheat must be declared as an allergen, barley and malt do not have the same labeling requirements and can be hidden. Look for phrases like "barley malt," "roasted barley," or "natural flavors" without a specified source. This is especially important for herbal and flavored teas, which are more likely to contain additional ingredients.

Choose Loose-Leaf Over Bags (When in Doubt)

Choosing loose-leaf tea, especially from reputable companies, can reduce the risk of hidden gluten in tea bags and additives. This is particularly useful if you are sensitive to even trace amounts of contamination from shared processing lines.

Conclusion

While pure teas like black, green, and white are naturally gluten-free, the presence of hidden gluten in specialty, herbal, and flavored blends is a significant risk for those with celiac disease or gluten sensitivity. Gluten can enter the manufacturing process through intentional additives like barley malt, or unintentionally through cross-contamination in shared facilities. The best strategy for a safe, gluten-free cup of tea is to choose certified gluten-free products, carefully read all labels for hidden ingredients, and opt for loose-leaf varieties when uncertain about a brand's processing methods.

Authoritative Outbound Link

For more detailed information on celiac disease and maintaining a gluten-free diet, consult the official website of the Celiac Disease Foundation(https://celiac.org/gluten-free-living/what-is-gluten/).

Frequently Asked Questions

No, not all green tea is guaranteed to be gluten-free. While pure green tea is naturally gluten-free, some brands add ingredients containing gluten, and many are at risk for cross-contamination during processing.

Yes, 'natural flavors' can sometimes be derived from gluten-containing sources. If you have celiac disease or are highly sensitive to gluten, it's best to contact the manufacturer to confirm the source of their flavorings.

Barley tea, known as Mugicha in Japan and Boricha in Korea, is a beverage made from roasted barley. As barley is a gluten-containing grain, this type of tea is not gluten-free and should be avoided.

The most reliable method is to check the ingredients list for gluten-containing items like barley, malt, or wheat grass. For packaged teas without a certified gluten-free label, it's best to contact the company for clarity on manufacturing practices and potential cross-contamination.

Some older tea bags or cheaper brands have been reported to use wheat-based glues for sealing. However, this is less common now, and many brands use heat seals. Still, for maximum safety, especially for those with high sensitivity, loose-leaf tea is the safest choice.

Yes, cross-contamination is a significant risk, particularly for flavored or blended teas. Surveys have detected gluten in products not intended to contain it, suggesting shared processing equipment is a common issue.

Yes, several tea companies offer certified gluten-free products, such as The Republic of Tea. Looking for a third-party certification seal, like the GFCO mark, is the best way to ensure safety.