To ensure a good dietary balance, we should eat fish twice a week including a fatty fish. But these recommendations do not specify the origin of the fish. So, in which ways are farmed fish or wild-caught fish different?

A very different environment,

Not only to meet demand, but also to save the species from early extinction and save them from intensive fishing, farmed fish make up a large part of our fish consumption.

Fish farming is carried out in freshwater or seawater basins, depending on the species, and is based on its natural life cycle. Obviously fish farming requires the intervention of  man. Depending on the type of farming, the fish are fed differently:

• Extensive farming: fish feed on resources naturally present in the basin

• Semi-intensive breeding: environment in which we add nutritional supplements.

• Intensive Farming: the diet is artificial, consisting mainly of plants, other fishmeal, vitamins and minerals.

But there’s no question of risking contamination and losing the whole production, so all the fish end up in the same state, and as result, the meal naturally contains antibiotics and pesticides!  SOURCE? Well, obviously, farmed fish must have exactly the same physical characteristics as wild fish, especially the same colour, so why not add a little colour to the food.

In contrast, wild fish live in their natural state: they feed on what they find and travel long distances. The food and their state of health can in no way be controlled. The problem is that even in deep waters, our waters are polluted. Fish are filled with pollutants that are stored in their fat.

And nutritionally, does it changes anything?

Not really. From a nutritional point of view, both wild and farmed fish are all low in calories, and are sources of a high quality protein and omega 3. In addition, seawater fish provide  vitamin B12, iodine, selenium and in fatty fish, vitamin D.

For wild-caught fish, it is the law of the strongest: the smaller ones are eaten by the bigger ones, and pollutants accumulate and concentrated. For farmed fish, they are much less active, so for an equivalent species they are much fatter and therefore contain more pollutants than a wild species.

You understand the mechanism, the bigger and fatter the fish, the more likely it is to contain a large amount of pollutants.

So yes, oily fish is good for your health, but a fatty fish that is even more contaminated and rich in colouring is not necessarily the best option. Moreover, if it is recommended to consume at least one fatty fish per week primarily for their omega 3 content, a major fatty acid in wild fish but less present in farmed fish. And yes, it has been proven that farmed fatty fish contains more omega 6 than omega 3. However, most diets are already overflowing with omega 6 and even if they are good for your health, we must limit their consumption.

There are no good or bad choices,

From a nutritional point of view, above all, it is the species and not the source that determines the nutritional composition of the fish. For the rest, again, everything has to be in balance, so by varying the species, the types of crops and the fishing areas, you will achieve a certain nutritional equilibrium and lower the risk of overloading your body with pollutants. Lastly, it’s important to point out that the recognised benefits of fish are significantly higher than the potential toxic risks.

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