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Is Tuna Keto-Friendly?

Tuna on a kitchen counter

Is Tuna Keto-Friendly? Well, the answer is a resounding yes!

In this article, we'll dive into the specifics of why tuna is a fantastic choice for those on a ketogenic diet.

We'll explore the carb content of tuna - hint: it's virtually zero - and discuss how it fits into a keto diet.

From simple tips on incorporating tuna into your keto meal plans to providing some tasty recipe ideas, we've got you covered!

Let's dive in!


  • Yes, tuna is keto-friendly with virtually zero carbs.
  • Tuna is high in protein and rich in certain vitamins and minerals, offering a host of nutritional benefits.
  • There are numerous ways to incorporate tuna into a keto diet, including some tasty recipe ideas.

Is Tuna Keto-Friendly?

Yes, tuna is keto-friendly. This is primarily due to its carb content, or rather the lack thereof. With 0.0g of carbohydrates per 100g serving, it meets one of the primary requirements of a keto-friendly food.

In addition to being low in carbs, being keto-friendly means that a food is low in sugars and high in healthy fats or proteins โ€” tuna fits this bill. It contains 24.4g of protein per 100g, making it a rich source of this macronutrient. Because of this, tuna is considered a good choice for those following a ketogenic lifestyle.

Can You Have Tuna on a Strict Keto Diet?

Yes, you can certainly include tuna in a strict keto diet. A strict keto diet typically involves consuming less than 20g of carbohydrates daily. Given that tuna contains 0.0g of carbs per 100g, it fits comfortably into this dietary pattern without disrupting ketosis.

For those on a more lenient keto or low-carb diet, where daily carb intake is limited to between 30-50g of net carbs, tuna is also a suitable option. With its absence of carbs, it leaves plenty of room for other food items with a higher carb content.

Carbs In Tuna

Tuna contains 0.0g of carbs per 100g serving. It's worth noting that these are net carbs, which are the total carbohydrates in a food minus the fiber.

Because tuna has no carbs, it's also accurate to say it has a glycemic index of zero. The glycemic index is a scale that ranks carbohydrates in foods on a scale from 0 to 100 based on how quickly and how much they raise blood sugar levels after eating. Given its lack of carbs, tuna can be regarded as a food that doesn't impact blood sugar levels.

Tuna Nutrition Facts

A 100g serving of Tuna comes packed with an array of nutrients. Let's delve into the specifics:

The macronutrients include 26g of protein, providing essential amino acids, and 1g of fat, with a focus on heart-healthy omega-3 fatty acids. No carbohydrates are found in Tuna.
As for micronutrients, Tuna excels in Vitamin D, with 39% of the daily value (DV), and Vitamin B12, offering a whopping 181% of the DV. It also supplies 13% of the DV for Iron and 15% for Magnesium.
The Omega-3 fatty acids in Tuna, including EPA and DHA, are known for their potential cardiovascular benefits. The high protein content aids in muscle repair and growth. Tuna's rich supply of Vitamin B12 supports neurological function, while Iron and Magnesium play crucial roles in overall body function.

Nutrient NameAmount and Unit per 100g
Total fats0.49g
Sodium, Na45.0mg
Potassium, K441.0mg
Magnesium, Mg35.0mg
Calcium, Ca4.0mg
Vitamin A18.0ug
Vitamin B-60.93mg
Vitamin B-122.08ug
Vitamin E (alpha-tocopherol)0.24mg
Vitamin K10.1ug
Copper, Cu0.04mg
Iron, Fe0.77mg
Phosphorus, P278.0mg
Selenium, Se90.6ug
Zinc, Zn0.37mg
Folate, total2.0ug
Choline, total65.0mg
Fatty acids, total saturated0.17g
Fatty acids, total monounsaturated0.12g
Fatty acids, total polyunsaturated0.15g
Nutritional data is sourced from the US Department of Agriculture's FoodData Central system. Please see Cast Iron Keto's editorial and research standards for more information.

Health Implications of Tuna on a Keto Diet

Tuna is a nutrient-rich food that offers numerous health benefits. It is high in protein (24.4g per 100g), which is essential for muscle growth and repair. It's also a good source of several vitamins such as Vitamin A, Vitamin B-6, Vitamin B-12, and minerals including Selenium, Iron, and Potassium that are crucial for different bodily functions.

However, despite its nutritional benefits, it's important to note that tuna can contain mercury, a heavy metal that can be harmful in large amounts. Therefore, moderate consumption is advised.

Incorporating Tuna into Your Keto Meal Plan

Tuna is quite versatile and can be added to various dishes.

  • For a simple and quick meal, try adding it to your salads or using it as a filling for lettuce wraps.
  • Make a keto tuna casserole or tuna patties using almond flour as a binder instead of bread crumbs.

While tuna has no carbs, it's important to keep track of the carbs in the other ingredients you're using in your meals. This will help ensure you stay within your daily carb limit.

Keto-Compatible Alternatives for Tuna

  1. Salmon: Like tuna, salmon is a keto-friendly option that is high in protein and rich in omega-3 fatty acids. You can use it in much the same way you would tuna: in salads, keto-friendly sushi rolls, or simply baked with some herbs and lemon.
  2. Chicken: This is another high-protein, low-carb option that can replace tuna in many recipes. It's versatile and can be used in everything from salads to soups to stir-fries, providing a different flavor profile while still keeping things keto-friendly.
  3. Sardines: Packed with protein and heart-healthy fats, sardines are another fish alternative to tuna. They can be enjoyed straight out of the can, or used in salads and other dishes.

Concluding Thoughts on Tuna and Keto

In conclusion, tuna is an excellent choice for those following a keto diet due to its high protein content and virtually no carbohydrate content. It not only aligns well with the strict carb restrictions of a keto diet but also offers a host of nutritional benefits, including a rich supply of certain vitamins and minerals.

The versatility of tuna also makes it easy to incorporate into various keto-friendly recipes, from salads to casseroles. However, keeping track of the carbs in other ingredients and practicing portion control remain important strategies to stay within your daily carb limit.

Explore our Is It Keto Knowledge Hub.

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Cast Iron Keto's Editorial and Research Standards

Certain rare or exotic food items may not have nutritional profiles in the FoodData Central database. If an exact match is not found in the FoodData Central database, then, the Cast Iron Keto team utilizes a three-prong approach to provide readers with the closest relevant nutritional data, where possible.

First, in the event that nutritional profiles for a rare or exotic food item are not available in the FoodData Central database, we investigate alternative names for that particular food item and use that data when possible. Second, in cases where no alternate names exist, Cast Iron Keto will use nutritional data for a close relative or similar food item. Finally, if no close relatives or similar items exist, we refrain from publishing nutrient data tables.

When making dietary or health decisions based on FoodData Central's data, we suggest readers consult with a nutritionist or other health experts, particularly if the food in question has a significant role in your diet or if you are using the food item to treat any health disorder(s).

Furthermore, it is important to note that even if a close relative or similar item is used to approximate the nutritional data, different food items can have varying levels of nutrients due to factors such as soil quality, farming practices, and regional differences.


The information on this website is only intended to be general summary information for public use, designed for educational purposes only, and is not engaged in rendering medical advice or professional services. This information does not replace written law or regulations, nor does it replace professional medical advice, diagnosis, or treatment. If you have questions about a medical condition or are seeking to evaluate the health merits of certain food items for the treatment of any medical condition, you should seek the advice of a doctor or other qualified health professionals.

The views expressed at, or through, Cast Iron Keto are for informational purposes only. Cast Iron Keto cannot guarantee the validity of the information found here. While we use reasonable efforts to include accurate and up-to-date information, we make no warranties as to the accuracy of the content and assume no liability or responsibility for any errors or omissions in the content. All liability with respect to actions taken or not taken based on the contents of this website are hereby expressly disclaimed. The content on this posting is provided "as is;" no representations are made that the content is error-free.

Frequently Asked Questions

Absolutely! Canned tuna, whether in water or olive oil, is a keto-friendly option as it contains virtually no carbs.

Generally, all types of tuna - be it albacore, skipjack, or yellowfin - are keto-friendly due to their high protein and low carb content. However, remember the nuances of the different types, such as slight variations in fat content and flavor.

While tuna is keto-friendly, it's important to practice portion control. Tuna contains mercury, and high consumption can lead to mercury buildup in the body.