Parasites in fish: What you need to know for safe consumption

You don't have to live by the sea to access fresh and healthy fish. Most large stores sell high-quality sea and ocean fish. However, some species may contain dangerous parasites that pose a health risk.

According to the World Health Organization's recommendations, fish should be eaten at least three times a week. Fish are an excellent source of protein and valuable omega fatty acids. However, it's crucial to be aware that fish meat can sometimes contain harmful parasites that can seriously threaten human health.

Eating fish carries the risk of infection with diseases such as diphyllobothriasis (tapeworms), opisthorchiasis (cat liver fluke), or anisakiasis (nematodes). Diphyllobothriasis can be particularly dangerous because tapeworms can reach lengths up to 10 metres (33 feet). Symptoms such as severe abdominal pain, diarrhea, and vomiting are typical of this disease, and if neglected, it can lead to vitamin B absorption disorders. Treatment for the parasitic infection is necessary.

Opisthorchiasis, an infection from the cat liver fluke, can affect not only domestic animals like dogs, cats, and foxes but also humans. Infection occurs after consuming caviar or undercooked fish meat. Anisakiasis involves nematodes that inhabit the lower parts of fish, causing damage to the walls of the stomach and intestines.

Infections from these parasites usually result from eating raw or undercooked fish. To protect yourself, subject the fish to thermal treatment at least 60 degrees Celsius (140 degrees Fahrenheit). When purchasing fish, paying attention to their country of origin is essential. These parasites are most commonly found in fish from Scandinavia, Japan, the Netherlands, and the Pacific coasts.

Certain fish species are better avoided due to a higher risk of infection. These include wild sea bass, ling, shark, mackerel, swordfish, oilfish, bluefin tuna, red snapper, herring, hake, rosefish, pollock, and turbot.