Is There a Keto-Friendly Soy Sauce?

December 12, 2025 •

4 min read

Most traditional soy sauces contain a surprisingly low carb count, making them technically keto-friendly in moderation. However, hidden ingredients, gluten content, and varying production methods mean not all varieties are created equal for those on a strict ketogenic diet.

Quick Summary

This guide reveals if traditional soy sauce fits a ketogenic diet, identifies hidden carbs to avoid, and provides healthier, soy-free substitutes and delicious keto-friendly recipes.

Key Points

Moderate Usage is Key: Traditional soy sauce is low in carbs, but its high sodium content and potential gluten require moderate use on a keto diet.
Avoid Sweet and Dark Varieties: Sweet and dark soy sauces often contain added sugars and molasses, making them unsuitable for keto.
Coconut Aminos for a Clean Alternative: Coconut aminos are a soy-free, gluten-free, and lower-sodium alternative, though they have a slightly higher carb count than regular soy sauce.
Tamari is a Gluten-Free Option: For those with gluten sensitivity, tamari is a safe, gluten-free soy sauce that offers a richer flavor.
Check Labels for Hidden Carbs: Always read nutrition labels to avoid hidden sugars and additives in store-bought sauces.
Homemade Offers Control: Crafting your own keto soy sauce from bone broth allows for complete control over ingredients and sodium content.
Fish Sauce for a Different Umami: Fish sauce is a virtually carb-free, strong umami option, but be mindful of its distinct flavor and high sodium.

Navigating the Keto-Friendly Soy Sauce Landscape

For many, the rich, umami flavor of soy sauce is a non-negotiable part of Asian-inspired cooking and marinades. When adopting a ketogenic lifestyle, scrutinizing every condiment becomes essential. The short answer is yes, most traditionally brewed soy sauces are low enough in net carbs to be considered keto-friendly, but with crucial caveats. Understanding the differences between types of soy sauce and their substitutes is key to staying in ketosis while enjoying full flavor.

What to Look For (and Avoid) in Your Soy Sauce

When scanning the labels, most light or regular soy sauces are safe, with approximately 1–2 grams of carbs per tablespoon. The primary risk comes from added sugars, which can be found in some varieties. Dark and sweet soy sauces, for instance, often contain added molasses or caramel, pushing their carb counts significantly higher—sometimes up to 5 grams per tablespoon. To ensure you're making the right choice, always read the ingredients list to spot any unnecessary additives. Traditional brewing methods are generally safer than chemically hydrolyzed versions, which can contain more fillers.

Keto Soy Sauce Alternatives for Healthier Choices

For those who prefer a cleaner approach to keto or need to avoid soy and gluten, several excellent alternatives provide a similar umami depth. Each comes with its own flavor profile and nutritional considerations, making it easy to find the perfect fit for your recipe.

Coconut Aminos: Made from the fermented sap of coconut blossoms, this soy-free and gluten-free alternative has a slightly sweeter, milder flavor than soy sauce. It's a popular option for paleo and clean keto diets, though you should note its carb count is slightly higher than traditional soy sauce (around 3 grams of net carbs per tablespoon).
Tamari Sauce: Often a byproduct of miso paste, tamari is a gluten-free soy sauce alternative that is typically richer and has a less salty, more complex umami flavor. While it contains soy, high-quality tamari can be a good choice for those with gluten sensitivities. One tablespoon typically has around 1 gram of carbs.
Liquid Aminos (Soy-Based): Made from treating soybeans with an acidic solution, this offers a soy sauce flavor without the fermentation process. When made from soy protein, it contains 0 grams of carbs per tablespoon, making it an excellent, carb-free option.
Fish Sauce: A staple in Southeast Asian cuisine, fish sauce is made from fermented fish and salt. It offers a powerful umami punch and is virtually carb-free. Its strong flavor means you typically use it in smaller quantities, and it provides a different, fishier, and saltier profile.

Homemade Keto Soy Sauce Recipe

If you want complete control over your ingredients and sodium levels, making your own keto soy sauce is a great option. This simple recipe offers a rich, umami flavor without any hidden sugars.

Ingredients:

1.5 cups beef or chicken bone broth
2 teaspoons apple cider vinegar
1/8 teaspoon ground ginger
1/16 teaspoon garlic powder
1/16 teaspoon onion powder
Salt to taste

Instructions:

Add all ingredients, except salt, to a saucepan and bring to a simmer over medium heat.
Maintain the simmer for about 15 minutes, allowing the liquid to reduce by approximately a third.
Season with salt to your preference, as the broth already contains some sodium.
Transfer to a jar and store in the refrigerator for up to one week. Shake well before each use.

Comparison of Keto-Friendly Soy Sauce Options


Feature	Regular Soy Sauce	Tamari Sauce	Coconut Aminos	Fish Sauce
Carb Count	Low (1-2g per tbsp)	Low (approx. 1g per tbsp)	Moderate (approx. 3g per tbsp)	Very Low (approx. 1g per tbsp)
Gluten-Free	No (typically contains wheat)	Yes (confirm label)	Yes	Yes
Soy-Free	No	No	Yes	Yes
Sodium Level	High	High (but often less than soy sauce)	Lower (70-75% less)	High
Flavor Profile	Salty, umami, balanced	Richer, earthier umami	Milder, slightly sweet	Strong, salty, savory, fishy
Best For...	General cooking (check labels)	Gluten-sensitive diets	Soy/gluten-free diets, marinades	Flavor boosting where fishy notes are desired

Conclusion: Making the Right Choice for Your Keto Diet

While a standard, traditionally brewed soy sauce is technically acceptable on a ketogenic diet due to its low carb count, it's not the cleanest option. Factors like high sodium, gluten, and potential GMO soybeans make alternatives more appealing for those following a strict or clean keto approach. Coconut aminos and tamari provide excellent, often healthier, replacements that are soy-free or gluten-free, respectively. Ultimately, the best choice depends on your specific health goals, dietary sensitivities, and flavor preferences. By being an informed consumer and reading labels carefully, you can still enjoy the deep, savory flavors you love without compromising your ketogenic lifestyle.

Frequently Asked Questions

Yes, regular soy sauce is generally considered keto-friendly due to its low carbohydrate count (typically 1-2 grams per tablespoon) and minimal sugar content. However, moderation is key, and it is not recommended for those on a strict, clean keto diet because of its high sodium, gluten, and potential GMO content.

Coconut aminos are widely regarded as the best keto-friendly alternative, especially for those avoiding soy and gluten. It is made from the fermented sap of coconut blossoms and offers a sweet, umami flavor with less sodium than traditional soy sauce.

For those prioritizing a 'clean keto' diet, coconut aminos are the better choice as they are soy-free, gluten-free, and lower in sodium. However, coconut aminos do contain a few more carbs per serving, so moderate use is still important to stay within daily carb limits.

Yes, you can use tamari on a keto diet. Tamari is a gluten-free soy sauce alternative with a rich umami flavor. While it contains soy, it is generally lower in carbs and a good option for those with gluten sensitivities. Always check the label to ensure it is certified gluten-free.

Yes, you should avoid dark and sweet soy sauces on a keto diet. These varieties often have added sugar, molasses, or other sweeteners to create a thicker texture and sweeter flavor, which significantly increases their carb content.

The carb count varies by alternative. Traditional soy sauce has around 1-2g carbs per tbsp, tamari around 1g, coconut aminos around 3g, and fish sauce around 1g or less. Liquid aminos from soy protein often have 0g carbs.

Beyond its low carb count, some consider traditional soy sauce unhealthy for a clean keto diet due to potential GMO soybeans, high sodium content, and gluten from the wheat used in fermentation. Alternatives like coconut aminos offer a cleaner option.