Does Low-Sodium Soy Sauce Contain Gluten?

October 31, 2025

Soy sauce is the soul of Chinese cooking — it brings depth, umami, and aroma to countless dishes.
As more people embrace a healthier diet, low-sodium soy sauce has become a popular choice.
However, for those who need to avoid gluten, one common question arises:
“Is low-sodium soy sauce also gluten-free?”
The answer: Not necessarily.
It depends on the product’s recipe and production process.
Let’s explore the connection between low-sodium soy sauce and gluten, so you can make informed and confident choices at the grocery store.

What Is Gluten? The “Elastic Protein” Hidden in Grains

Think of gluten as a protein glue that holds food together.
It’s a group of proteins found in wheat, barley, and rye, responsible for giving dough its elasticity and chewiness.
That sticky, stretchy substance you see when washing dough — that’s gluten.
It’s what makes bread fluffy and chewy, and noodles firm and springy.
In short, gluten is the secret behind the “bite” of wheat-based foods.

Why Gluten Can Be Harmful to Some People

For most people, gluten is harmless and digestible.
But for certain groups — celiac disease patients, gluten-sensitive individuals, or those allergic to wheat — avoiding gluten is crucial to maintaining health.

- 1. Celiac disease: The immune system mistakenly attacks the small intestine’s lining after consuming gluten. This damages the intestinal villi (responsible for nutrient absorption), leading to chronic diarrhea, bloating, anemia, and nutrient deficiencies.
  2. Non-celiac gluten sensitivity:While it doesn’t harm the intestines, it still triggers uncomfortable symptoms such as bloating, abdominal pain, diarrhea, constipation, fatigue, and brain fog.
  3. Wheat allergy:This is an acute allergic reaction. The immune system treats wheat proteins (including gluten) as harmful invaders, causing rash, throat swelling, or even life-threatening anaphylaxis within minutes or hours after exposure.

“Low Sodium” ≠ “Gluten-Free”

So, what’s the relationship between sodium and gluten?
In fact, they are two completely different product attributes.

“Low sodium” means the product contains less sodium compared to regular soy sauce, often achieved by reducing salt, using potassium chloride, or employing special brewing methods.
“Gluten-free” means the product does not contain gluten—the protein naturally found in wheat, barley, and rye.

Therefore, a soy sauce can be low-sodium but contain gluten, or be gluten-free but not low-sodium, or be both low-sodium and gluten-free (if brewed with alternative grains).

Why Most Traditional Low-Sodium Soy Sauces Contain Gluten

Traditional soy sauce is typically made from four ingredients: soybeans, wheat, salt, and water.
Among these, wheat is the main source of gluten.
During fermentation, wheat contributes sweetness and complexity to the sauce’s aroma and flavor.
Thus, even when salt content is reduced, most low-sodium soy sauces still use wheat, meaning they are not gluten-free.

How to Identify Gluten-Free Soy Sauce

If you have celiac disease, gluten intolerance, or wheat sensitivity, simply choosing “low sodium” isn’t enough. Here’s how to ensure your soy sauce is safe for you:

Read the Ingredient List Carefully
Look for a “Gluten-Free” Certification Label
Explore Common Gluten-Free Alternatives

Gluten-Free Soy Sauce: Brewed with rice, buckwheat, or corn instead of wheat, eliminating gluten from the start.
Tamari Soy Sauce: A Japanese-style soy sauce traditionally brewed from only soybeans, with little to no wheat—but always confirm the label.
Coconut Aminos: Made from fermented coconut blossom sap and salt, naturally gluten-free with a mild, sweet flavor that differs from traditional soy sauce.

Conclusion

In summary, low-sodium soy sauce is not automatically gluten-free.

For those who must strictly avoid gluten, developing the habit of reading labels and recognizing gluten-free certifications is the best protection for your health.

By understanding ingredients and production processes, you can confidently enjoy delicious, flavorful dishes — without compromising your well-being.

FAQ

Q1:I’m highly sensitive to gluten. Is it risky to consume regular low-sodium soy sauce?
Yes, it’s risky. If the product contains wheat, it contains gluten. Even trace amounts may trigger a reaction in people with celiac disease or high sensitivity. Always choose soy sauces clearly labeled “gluten-free” with no wheat in the ingredients list.

Q2:How can I avoid gluten when dining out?
Always ask restaurant staff whether the dishes contain soy sauce, and specify that you need gluten-free food.
Request gluten-free soy sauce or ask for meals without soy sauce added. The safest approach is to dine at restaurants that clearly offer gluten-free menu options.