ACCORDING TO A FISHERMAN CANNED FISH IS HEALTHIER THAN TUNA

More omega-3s and less mercury: Canned fish is healthier than tuna, says a fisherman.

According to the expert, tuna is preferred due to marketing strategies, while this fish is often overlooked in supermarkets.
Canned tuna is a must-have in almost every refrigerator. It is used in salads, pasta, sandwiches and omelets. It is rich in protein. But fisherman and nutrition educator Fran Rodriguez argues that there is another type of canned fish that is lesser known but deserves much more attention: mackerel. According to El Espanol news…

“If you’re eating tuna, it’s because it’s a marketing tactic, because mackerel is a nutritious fish,” Rodriguez noted.

Their arguments are based on several differences in the nutritional value of the two fish species.
“Mackerel contains more omega-3s, less mercury, more vitamin D, has a richer flavor and is generally cheaper,” explained Rodriguez.
However, as stated in the publication, tuna is not actually a food with poor nutritional value, and its consumption is not just a marketing tactic. It contains proteins, vitamins and minerals of high biological value and is considered an oily fish recommended for inclusion in a healthy diet. It has also been noted that mackerel contains more nutrients than tuna, especially in terms of some fatty acids.

Omega-3 content

One of the most striking examples is omega-3. According to the Spanish Heart Foundation, mackerel contains about 2.67 grams of omega-3s per 100 grams, while tuna contains about 1.29 grams. These values may vary depending on the type of fish, time of year, and whether the fish is fresh or canned. However, they represent an important difference.

In the published text, it was explained that omega-3 fatty acids EPA and DHA, found in oily fish, play a role in many processes in the body. The Spanish Nutrition Foundation lists oily fish, especially mackerel, sardines, salmon and tuna, as major marine sources of these fatty acids.

Mackerel also contains high amounts of micronutrients. It is known to be a source of vitamin D, vitamin B12, selenium, phosphorus and potassium and to contain high-quality protein.

Protein content

“But this does not mean that mackerel is superior to tuna in every respect. Tuna, especially some canned varieties, may contain more protein per 100 grams of product,” the article states.
Rodriguez himself acknowledged that both types of fish are good sources of protein. According to him, if you consistently opt for tuna, you may be underestimating other fish that combine protein with plenty of healthy fats.

Mercury content

Another important difference is the mercury content. The Spanish Agency for Food and Nutrition Safety (AESAN) explained that large predatory fish with long life cycles tend to accumulate more of this contaminant due to bioaccumulation along the food chain. Species classified as high in mercury include bluefin tuna (Thunnus thynnus), swordfish, some shark species and pike. However, the Spanish agency lists mackerel as a species with low mercury levels.

The publication made an important clarification here: Not all tuna sold in canned form is red tuna. Different types of tuna can be used in canned products, and the mercury concentrations in them can vary significantly. Therefore, it cannot be assumed that every can of tuna necessarily contains high levels of mercury.
How much fish should you eat?
AESAN’s advice for the general population remains unchanged: Eat three to four servings of fish per week, rotating different types and eating a combination of white and oily fish. The agency recommends that pregnant women, those planning to become pregnant or who are breastfeeding, as well as children under the age of 10, avoid fish species containing high mercury.

AESAN agency lists mackerel among the oily fish that should be preferred as part of healthy and sustainable diet guidelines. He also states that canned fish maintains similar nutritional value to fresh fish, but recommends choosing low-salt varieties whenever possible.

Why is tuna more popular?

Rodriguez also noted the economic factor. He believes the immense popularity of canned tuna has made it an automatic choice for many consumers, even though mackerel, sardines and other oily fish have similar or even better nutritional value and are sometimes cheaper.
As the published article notes, the claim that mackerel is “much more nutritious” is overly simplistic, as it all depends on the specific nutrient being evaluated. While tuna remains an excellent source of protein and other nutrients, mackerel has distinct advantages: it generally contains more omega-3s, is rich in vitamin D, and is considered a low-mercury type of fish by AESAN.