Canned tuna contains mercuryas well as the meat of other large fish such as shark, swordfish, pike and hake. Some compounds that contain this element and are found in fish, such as methylmercurycan cause damage to our body, but if we do not consume them in excessive quantities there is no danger to our health.
This is confirmed by theEuropean Food Safety Authorityaccording to which under the 4 portions of fish per week the benefits of this food (due to the content of vitamins, omega-3 and highly digestible proteins) outweigh the risks due to methylmercury. The recommended portions apply to adult males and women beyond menopause, while they drop to 2-3 small fish per week (for example mackerel, sea bream and trout) for children, women of childbearing age, pregnant women and breastfeeding women. These recommendations are due to the fact that children are more vulnerable to methylmercury, which at high doses can affect brain development, with possible effects on language, memory and attention.
Therefore, according to the authorities, fish can be eaten safely without problems for your health, as long as you do not exceed the recommended doses.
Mercury accumulates in larger fish through a process called biomagnification: Large predators eat smaller fish, which in turn feed on contaminated shellfish, and so on. In practice, mercury accumulates the more you go up the food pyramid. The origin of mercury is on the one hand its natural presence on the earth’s crust, on the other hand human activities such as industrial processes and metal extraction, which release this element into the environment.
