What are the healthiest fish?
Two factors must be taken into account: that they are rich in omega-3 fatty acid and have low levels of mercury, a toxic element that accumulates in some large species.
As paradoxical as it may be, the more fat a fish contains, the more benefits it brings to health. After all, we must not forget that this fat is mainly made up of omega-3, a fatty acid that is unable to produce our body by itself. This compound today so prestigious reduces cholesterol levels in blood, keeps our arteries healthy and free of thrombi and prevents heart problems. In addition, it naturally reduces blood pressure levels. But, what are the best sources of this nutrient?
The so-called whitefish - cod, sole, monkfish, hake, turbot ... - is sedentary, does not need to stockpile large reserves of energy and only has 1-2% of fat in your body. Of course, it is a very healthy source of protein and low calorie, in addition to providing B vitamins. For its part, blue fish such as sardines, salmon and tuna are globetrotters, make long journeys throughout their lives and that leads them to accumulate between 5% and 10% of fat between their muscles. Taking into account that they also provide protein in quantity and quality similar to eggs and meat, their gastronomic and nutritional cache is now skyrocketing.
According to the latest research, the consumption of omega-3 not only improves our cardiovascular health, but also benefits the functioning of the brain. A study by the University of Alberta (Canada) showed that the neurons responsible for storing information in the hippocampus, the seat of memory, communicate better with each other when omega-3 levels are high. Also, that this nutrient flows in our veins in abundance prevents depression and improves mood. As if that were not enough, another recent research from the University of Oxford, in the United Kingdom, has shown that its consumption improves the quality of sleep, since it reduces the problems to reconcile it and nighttime interruptions.
The big fish eats the mercury
But, attention, ichthyophagous! Eating fish in large quantities also has its contraindications, especially if we take into account that some of them are more prone to accumulate mercury. Specifically, this harmful substance would be more present in large fish, the predators that are at the end of the food chain. For example, sharks eat many small fish, which in turn ingest the mercury deposited in the plankton ... Apart from this shark, other species available in fishmongers, such as swordfish, mackerel and blanquillos (from the family Malacanthidae), may also contain high doses of the chemical element.
Mercury should be avoided, especially by pregnant women and young children - up to 30 months - as it can affect the neurological development of both fetuses and the individual during their early childhood. Anyway, the experts do not advise to totally eliminate the fish mentioned from the diet, but limit their consumption to twice a week.
Optimal options if we combine the high content of omega 3 with low levels of mercury would be salmon, trout, herring, sardines and, among shellfish, oyster.
