The Spanish Agency for Food Safety (AESAN) has tightened recommendations on the consumption of certain foods, such as tuna and swordfish, as well as some crustaceans and vegetables, due to its high content of mercury, cadmium and nitrates, respectively. Specifically, the AESAN recommends that neither pregnant or lactating women, nor children under three years consume swordfish, shark or bluefin tuna, and that children from three to 12 years do not exceed 50 grams per week, due that the mercury they contain can cause serious alterations in the neuronal development of the fetus and young children.

Mercury can cause serious alterations in the neural development of the fetus

The organic form of mercury, the methylmercury, is very toxic and accumulates in the fatty tissues of large fish when they ingest other species that contain it. As it is about migratory fish, the danger can not be ruled out even though they have been fished in uncontaminated waters.

In the case of vegetables, the problem is nitrates, salts that in the human body are transformed into nitrites, which are toxic in high concentrations and can cause cyanosis (lack of oxygen in the blood) to babies. The greatest danger of nitrate intake is in the age range of one to three years, and the vegetables that have higher levels of nitrates are chard, spinach and lettuce, so their consumption in young children should be moderate .

It does not affect all consumers

The European Food Safety Authority (EFSA) does not consider it dangerous for children over the age of seven to take complete servings of these vegetables, which should be avoided, as a precaution, in babies under one year of age. The EFSA also warns that, once cooked, these vegetables should be kept in the refrigerator, because leaving them at room temperature overnight can make nitrates turn into nitrites.

It is important to emphasize that the consumption of vegetables offers great advantages in comparison with the possible risks, so they should not be banished from the diet at all. In addition, vegetables grown outdoors and with more hours of sun exposure contain less nitrate than greenhouse, or those from northern European countries.

The consumption of crustaceans it's much less frequent but the cadmium, a heavy metal generated by mining and industrial activities and by the use of some fertilizers, is found in high concentrations in crustaceans such as crab, crab or spider crab, and when ingested it accumulates in the human body, especially in liver and kidneys, and can damage kidney function. The recommendations on seafood consumption are focused on avoiding the head of prawns, crayfish, prawns, etc., because this is where the cadmium is concentrated, not being dangerous to health the intake of white meat of the appendages and abdomen, where the presence of metal is low.

For its part, the Minister of Health, Leire Pajín, wanted to reassure the rest of the consumers, explaining that they can continue to consume these foods with full guarantee for their health, since AESAN has directed the recommendation to reduce consumption only in the in some sectors of the population, such as children and pregnant women, in order to reduce risks.

Source: Spanish Agency for Food Safety (AESAN)

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