You could be eating shark meat and not know it. So why should you bother? After all, fish is fish and why should sharks be an exception?
First of all, shark meat contains high mercury levels, and is therefore not healthy. The American Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA) are advising women who may become pregnant, pregnant women, nursing mothers, and young children to avoid eating shark meat and fins
(Source http://water.epa.gov/scitech/swguidance/fishshellfish/outreach/advice_index.cfm)
Almost all shark populations are overfished, and most of the time, you just do not know which species you are eating.
Shark meat is often sold under a different name. It can be called ‘flake’, or even rock salmon’rock, dogfish, rigg or rock eel. Flake can be any kind of shark, and sometimes it is even sold as ‘baby flake’, meat of juvenile sharks, that have not even had the opportunity to reproduce. This kind of shark fishing is highly unsustainable.

“Baby flake”
Also, customers are deliberately misled. Hardly anyone being served the traditional ‘fish and chips’ suspects that shark is being served…
In general, choose sustainable fish, that does not come from nearly depleted stocks. Ask your fishmonger or chef what is actually being served!
More info: http://www.fishonline.org/
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