Why Can Celiacs Eat Soy Sauce? Understanding the Gluten-Free Alternatives

December 9, 2025 •

4 min read

Most people with celiac disease believe traditional soy sauce is forbidden, but a variety called tamari, made almost entirely from soybeans, is a safe and flavorful alternative. Understanding the difference is crucial for anyone following a gluten-free lifestyle, and modern culinary options ensure no flavor is sacrificed.

Quick Summary

Traditional soy sauce isn't gluten-free due to its wheat content, but safe alternatives like tamari, certified gluten-free brands, and coconut aminos are widely available for celiacs.

Key Points

Traditional soy sauce contains wheat: Most mainstream soy sauce brands are not gluten-free because wheat is a core ingredient in the fermentation process.
Tamari is a common gluten-free alternative: This Japanese-style sauce is typically brewed with 100% soybeans, not wheat, though celiacs should always check the label for certification.
Certified gluten-free soy sauce is guaranteed safe: Manufacturers also produce wheat-free soy sauces that are tested and certified to contain less than 20 ppm of gluten.
Coconut aminos offer a soy-free, gluten-free option: Derived from fermented coconut sap, this alternative provides a similar savory flavor profile and is naturally free of both soy and gluten.
Label vigilance is essential for celiacs: Never assume a product is gluten-free. Read the ingredient list and look for explicit certification to ensure safety.
Cross-contamination is a serious risk: When dining out, always inform your server of your gluten-free needs and consider bringing your own sealed bottle of tamari or gluten-free soy sauce for dipping.

The Misconception: Why Standard Soy Sauce is NOT Gluten-Free

For many with celiac disease or gluten sensitivities, soy sauce is viewed as an off-limits condiment. This assumption is largely correct when it comes to standard, traditionally brewed soy sauce. The confusion arises because the primary ingredient is 'soy,' which is naturally gluten-free. However, the brewing process for most popular soy sauces, including many Chinese and Japanese varieties, involves a key ingredient that contains gluten: wheat.

The Brewing Process of Traditional Soy Sauce

To create the complex umami flavor profile of traditional soy sauce (known as shoyu in Japan), a mixture of steamed soybeans and roasted, crushed wheat is fermented with a mold culture called Aspergillus. This mixture, known as koji, is then combined with a saltwater brine (moromi) and left to age for months. The enzymes from the mold break down the wheat proteins, but traces of gluten still remain in the finished product. While some brands, like Kikkoman, state that the gluten content is minimal, they cannot guarantee a gluten-free product, and it is not safe for individuals with celiac disease.

The Gluten-Free Alternatives Celiacs Can Enjoy

Fortunately, the demand for gluten-free products has led to a variety of safe alternatives that offer the same savory, umami flavor. These substitutes are either made without wheat or are naturally derived from gluten-free sources.

Tamari: The Wheat-Free or Low-Wheat Option

Tamari is a Japanese-style soy sauce that is often naturally gluten-free, as it is typically made using 100% soybeans with no wheat added. It was originally a byproduct of miso paste production. The resulting flavor is richer, darker, and less salty than traditional soy sauce. While many tamari brands are wheat-free, it is essential to check the label, as some manufacturers may include a small amount of wheat. Brands like San-J and Kikkoman's gluten-free tamari are certified to be safe for celiacs.

Certified Gluten-Free Soy Sauce Brands

In addition to tamari, many companies now offer a specifically formulated gluten-free version of soy sauce that mimics the flavor of the traditional product. These are brewed using alternative grains, such as rice, or solely with soybeans, and are rigorously tested to ensure they meet the FDA's standard of less than 20 parts per million of gluten. Always look for a 'certified gluten-free' label on the packaging to ensure it is safe to consume.

Coconut Aminos and Liquid Aminos

For those seeking alternatives entirely free from soy, coconut aminos and liquid aminos are popular choices. Coconut aminos are made from fermented coconut blossom sap and salt, resulting in a sauce that is naturally gluten-free and soy-free. Liquid aminos are a non-fermented, chemically produced seasoning made from a solution of amino acids derived from soybeans. Both offer a savory, salty taste similar to soy sauce, making them excellent substitutes in marinades, stir-fries, and dressings.

How to Identify Safe Soy Sauce for Celiacs

To protect yourself from accidental gluten exposure, follow these steps when purchasing soy sauce:

Read the Ingredients List: Traditional soy sauces will list 'wheat' as an ingredient. Avoid any product that lists wheat unless it is also certified gluten-free.
Look for Certification: The most reliable method is to check for a 'Certified Gluten-Free' label or a symbol from a recognized coeliac society.
Consider Tamari: While most tamari is safe, don't assume. Find a brand like San-J that is explicitly certified gluten-free.
Be Aware of Cross-Contamination: At restaurants or buffets, assume all soy sauce contains gluten unless you can verify it is a safe brand. Always inform your server of your dietary restrictions.
Explore Alternatives: Keep coconut aminos or liquid aminos on hand as a foolproof, naturally gluten-free replacement.

Comparison of Soy Sauce Types for Celiacs


Feature	Traditional Soy Sauce	Tamari	Certified GF Soy Sauce	Coconut Aminos
Primary Ingredients	Soybeans & Wheat	100% Soybeans or less wheat	Soybeans (with no wheat) or rice	Fermented coconut sap
Gluten Content	Contains gluten	Typically gluten-free, but check label	Guaranteed <20ppm gluten	Naturally gluten-free
Flavor Profile	Balanced, savory, slightly salty	Richer, less salty, deeper umami	Balanced, often similar to traditional	Sweeter, less salty, milder taste
Celiac Safety	Not safe	Typically safe, verify label	Safe	Safe

Preventing Cross-Contamination

Even with gluten-free soy sauce, cross-contamination is a significant risk, especially when dining out. In your own kitchen, designate separate bottles for gluten-free use. When eating at a restaurant, it's safest to bring your own bottle of certified gluten-free soy sauce if you plan to use it for dipping, such as with sushi. When ordering cooked dishes, explicitly ask that gluten-free soy sauce be used and ensure proper precautions are taken to prevent contact with gluten-containing ingredients.

Conclusion: Safe and Flavorful Options for Celiacs

The idea that all soy sauce is forbidden for celiacs is a myth rooted in the traditional brewing process. By understanding the ingredients and production methods, individuals on a gluten-free diet can make informed choices. Options like tamari and certified gluten-free soy sauce offer the rich, savory flavor of traditional varieties without the risk of gluten exposure. With a wide array of safe products available, from tamari to coconut aminos, celiacs can continue to enjoy the distinctive umami taste in all their favorite Asian-inspired dishes. Always remember to check labels and prioritize certified products to ensure your health and safety.

For more information on safe gluten-free food options, visit BeyondCeliac.org.

Frequently Asked Questions

No, not all tamari is gluten-free. While most modern tamari is made without wheat, some traditional or niche brands may include a small amount. Always check for a 'Certified Gluten-Free' label to be sure.

Traditional soy sauce is typically brewed with a mixture of soybeans and wheat. The wheat contains gluten, and even after fermentation, enough of the gluten protein remains to cause a reaction in those with celiac disease.

The most reliable way is to check the ingredients list. Any traditional soy sauce will list wheat. If it is an alternative, it should explicitly state its gluten-free status or list ingredients that do not contain wheat, barley, or rye.

Low-sodium soy sauce is not automatically gluten-free. Most low-sodium varieties are made from the same traditional wheat-and-soybean formula as regular soy sauce. You must find a specifically labeled 'gluten-free' or 'tamari' brand.

It is not safe to assume that soy sauce at a restaurant is gluten-free. Many eateries use traditional soy sauce. Always speak with your server about your celiac disease and confirm that they use a certified gluten-free brand and take precautions against cross-contamination.

Tamari, being made predominantly from soybeans, has a richer, deeper umami flavor and is generally less salty than traditional soy sauce, which has a more balanced taste due to its wheat content.

Coconut aminos are a popular alternative. They are made from fermented coconut blossom sap and salt, providing a savory, slightly sweet flavor that is both soy-free and gluten-free.

No, fermentation does not eliminate all the gluten. While the process may break down some gluten proteins, enough remains in the final product to be unsafe for those with celiac disease.