As paradoxical as it may be, the more fat a fish contains, the more health benefits it has. After all, we must not forget that this fat is made up mainly of omega-3, a fatty acid that our body is unable to produce on its own. This compound so prestigious today reduces blood cholesterol levels, 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 white fish – cod, sole, monkfish, hake, turbot … – is sedentary , does not need to store large energy reserves and only has 1-2% fat in its body. Of course, it is a very healthy and low-calorie source of protein, in addition to providing B complex vitamins. On the other hand, oily fish such as sardines, salmon and tuna are globetrotters , they make very long trips 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 proteins in quantity and quality similar to eggs and meat, their gastronomic and nutritional cache is through the roof at this point.
According to the latest research, consuming omega-3s not only improves our cardiovascular health, but also benefits brain function. A study from the University of Alberta (Canada) showed that neurons in charge of storing information in the hippocampus, the seat of memory, communicate better with each other when omega-3 levels are high. Likewise, that this nutrient flows in abundance through our veins prevents depression and improves mood . As if that were not enough, other recent research from the University of Oxford, in the United Kingdom, has brought to light that its consumption improves the quality of sleep , as it reduces the problems to fall asleep and the interruptions at night.
The big fish eats the mercury
But, attention ichthyophagus! 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, predators 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 tilefish (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. In any case, experts do not advise to completely eliminate the aforementioned fish from the diet, but to imitate their consumption twice a week .
Optimal options if we combine the high omega 3 content with the low mercury levels would be salmon, trout, herring, sardine and, among shellfish, oyster .
