Tofu is classified as Limited under standard keto guidelines — firm tofu contains approximately 1–2g of net carbohydrates per 3-ounce serving, making it the most keto-compatible plant-based protein source in published keto references.
Key Takeaways
- Tofu is classified as Limited under standard keto guidelines.
- Firm tofu contains approximately 1–2g net carbohydrates per 3-ounce serving.
- Lower in carbohydrates than most other legume and plant protein products.
- Flavored and marinated tofu products require label review for added sugar.
Classification Overview
Tofu is made from coagulated soy milk pressed into blocks. Its processing removes most of the soy carbohydrate content, resulting in a low-carbohydrate plant protein.
Firm and Extra-Firm Tofu
Firm and extra-firm tofu contain approximately 1.5–2g of net carbohydrates per 3-ounce serving. The pressing process removes much of the water and soybean liquid content, concentrating the protein and reducing the remaining carbohydrates. Published keto references classify firm and extra-firm tofu as generally compatible with keto carbohydrate budgets.
Silken Tofu
Silken tofu is softer and has a higher water content than firm tofu. It contains approximately 2–3g of net carbohydrates per 3-ounce serving — slightly more than firm varieties. Published keto references use silken tofu in desserts, smoothies, and creamy sauce applications.
Comparison with Tempeh
Firm tofu (1–2g net carbs per 3 oz) has substantially fewer carbohydrates than tempeh (7–9g net carbs per 3 oz). Both are soy-derived proteins classified as Limited, but tofu’s lower carbohydrate content makes it more readily compatible with strict keto carbohydrate limits. Published keto references more frequently recommend tofu over tempeh as a plant-based protein source.
Flavored and Pre-Marinated Varieties
Commercial marinated, baked, and flavored tofu products may contain significant added carbohydrates from teriyaki, barbecue, or sweet and sour marinades. These can be label-reviewed. Plain tofu marinated at home with keto-compliant seasonings is the standard keto reference approach.
Summary
Tofu is classified as Limited under standard keto guidelines. Plain firm tofu contains approximately 1–2g of net carbohydrates per 3-ounce serving — among the lowest carbohydrate contents of plant-based protein foods and compatible with standard keto carbohydrate budgets. Published keto references include plain tofu as the primary plant-based keto protein option. Flavored and marinated tofu products require label review for added carbohydrates.
This is reference-only classification content and does not constitute medical or dietary advice.