Is Canned Mackerel a Processed Food?

January 4, 2026 •

4 min read

According to the NOVA classification system, which categorizes foods by processing level, canned mackerel is considered a processed food. However, this designation doesn't automatically make it unhealthy, as the term 'processed' covers a wide spectrum of food production methods.

Quick Summary

Canned mackerel is a processed food, meaning it has undergone a canning process involving steaming and sterilization to enhance its shelf life. It is not ultra-processed and can be a healthy, nutritious option, often providing essential nutrients like omega-3 fatty acids.

Key Points

Processed, Not Ultra-Processed: Canned mackerel is a processed food, but it is not ultra-processed and retains significant nutritional value.
NOVA Classification: The NOVA system places canned fish in Group 3 (Processed), which is a lower level of processing than Group 4 (Ultra-processed).
Nutrient-Rich: The canning process preserves key nutrients like omega-3 fatty acids, protein, and calcium.
Minimize Additives: Opt for varieties packed in water or olive oil to avoid excessive salt and unnecessary additives.
Healthy and Convenient: Canned mackerel is a convenient, shelf-stable, and healthy option for a quick protein boost.
Bones Provide Calcium: The softened bones in canned mackerel are edible and contribute a good source of calcium to your diet.

What Exactly Is a Processed Food?

The term 'processed food' can be confusing, as it encompasses a broad range of products that have undergone any alteration from their natural state. The NOVA food classification system, developed by scientists in Brazil, offers a more nuanced way to understand processing levels. It categorizes foods into four groups:

Group 1: Unprocessed or minimally processed foods. These are foods altered slightly without adding other substances. Examples include fresh fruits, vegetables, and fish.
Group 2: Processed culinary ingredients. These are derived from Group 1 foods and used in preparing meals. Examples include salt, sugar, and oils.
Group 3: Processed foods. These are made by combining Group 1 and Group 2 foods and are modified to increase their shelf life or improve palatability. Canned fish and vegetables fall into this category.
Group 4: Ultra-processed foods. These are made from formulations of ingredients derived from foods and additives, with little to no resemblance to their original state. Examples include packaged snacks, sodas, and frozen meals.

Where Canned Mackerel Fits In

Canned mackerel is a processed food (NOVA Group 3). The process involves several steps:

Preparation: Fresh mackerel is cleaned and cut into fillets or pieces.
Soaking: The fish is often soaked in a brine (salt solution) to enhance flavor.
Canning: The fish is packed into cans along with a liquid, such as water, brine, or olive oil.
Heat Processing: The sealed cans are heated to a specific temperature for a set time to sterilize the contents, ensuring food safety and extending shelf life.

This process is distinct from creating ultra-processed foods, which often contain excessive amounts of added sugars, salts, fats, and artificial additives. While some canned mackerel might contain added salt or flavored sauces, the core product remains a minimally altered fish.

Canned Mackerel vs. Other Processed Foods: A Comparison


Feature	Canned Mackerel	Ultra-Processed Snack (e.g., Potato Chips)
Processing Level	Processed (NOVA Group 3)	Ultra-processed (NOVA Group 4)
Core Ingredient	Whole fish	Potatoes processed into a snack form
Key Nutrients	Omega-3s, protein, calcium	High in salt, saturated fat, potentially trans fats
Additives	May contain brine, oil, or flavored sauces; minimal additives	Often contains flavorings, preservatives, and emulsifiers
Health Impact	Can be a very healthy source of protein and fats	Linked to health issues like heart disease
Convenience	Excellent source of convenient, shelf-stable protein	High convenience, but with lower nutritional value

Is Canned Mackerel Healthy?

Despite being processed, canned mackerel can be a very healthy part of your diet. The key benefits include:

Rich in Omega-3s: Mackerel is an excellent source of omega-3 fatty acids, which are beneficial for heart health. The canning process does not significantly diminish this key nutrient.
High in Protein: It provides a great source of lean protein, which is essential for building and repairing tissues.
Good Source of Calcium: The canning process softens the bones in mackerel to the point where they are edible, providing a great source of dietary calcium.
Convenience and Affordability: Canned mackerel offers a cost-effective and shelf-stable way to include more fish in your diet.

What to Look For

To make the healthiest choice, consider these tips:

Check the ingredients: Opt for mackerel canned in water or olive oil to minimize unnecessary additives. Avoid varieties with high-sodium sauces or added sugars.
Rinse if necessary: If you're concerned about salt, rinsing the mackerel can help reduce the sodium content.
Look for certifications: Some brands carry certifications like the Marine Stewardship Council (MSC) label, which indicates sustainable sourcing.

Conclusion: A Healthy Addition to Your Pantry

Canned mackerel is, by definition, a processed food, but this classification alone does not mean it is unhealthy. The canning process is a minimal form of processing that preserves the fish while retaining its excellent nutritional profile, including heart-healthy omega-3s and high-quality protein. Unlike ultra-processed snacks laden with artificial ingredients, canned mackerel can be a nutritious and convenient part of a balanced diet. By choosing varieties packed in water or olive oil and being mindful of added salt, you can ensure you are making a healthy and informed choice.

For more in-depth information on food processing, you can consult resources like the Harvard T.H. Chan School of Public Health's guide to processed foods.

The Health Benefits of Canned Mackerel

Rich in Omega-3 Fatty Acids: Canned mackerel is packed with EPA and DHA, essential for brain health and reducing inflammation.
Excellent Source of Protein: A single serving provides a substantial amount of protein to support muscle repair and growth.
High in Vitamin D and Vitamin B12: These nutrients are crucial for bone health and nerve function, respectively.
Source of Calcium: The softened, edible bones in canned mackerel contribute to your daily calcium intake.
Convenient and Accessible: Its long shelf life and affordability make it a pantry staple for quick, nutritious meals.

Frequently Asked Questions

No, canned mackerel is not considered an ultra-processed food. While it is processed, the term 'ultra-processed' is reserved for foods that have undergone heavy industrial processing and contain many added ingredients and additives.

The NOVA classification system categorizes foods into four groups based on the extent of their processing, from unprocessed (Group 1) to ultra-processed (Group 4). This helps consumers make more informed decisions about the foods they eat.

No, the canning process does not destroy the omega-3 fatty acids in mackerel. In fact, it's an excellent way to get these healthy fats, as the processing helps preserve them.

While some canned mackerel is packed in brine with added salt, you can minimize your intake by choosing varieties packed in water or olive oil. You can also rinse the fish before eating to remove some of the excess sodium.

Yes, canned mackerel is a good source of calcium because the heat from the canning process softens the bones, making them completely edible and digestible.

Canned mackerel retains most of the nutritional benefits of fresh mackerel, including protein and omega-3s. Its main difference lies in the potential for added salt and the softened texture due to processing.

Look for labels that state the fish is packed in water or olive oil. Checking for the Marine Stewardship Council (MSC) label can also indicate that the fish was sourced sustainably.