Not all seafood is created equal when it comes to human consumption. Some seafood is harvested using methods that are destructive to the habitat they live in, like destroying reefs or bottom habitat. Several species are “overfished,” meaning that over time we have taken so many of them out of the sea, their numbers are critically low and we need to give the population time to rebuild. Some practices for farmed seafood include genetic modification, using antibiotics, and growth hormones, which then make their way into the people who eat them. And some seafood is considered high with levels of contaminants, like mercury or PCB’s, depending on where the seafood is from.
We should all try to be informed consumers about which seafood is the best choice, given all these fators. Here’s one really neat graphic depicting which fish are the best choice to eat: http://bit.ly/WlXosq
Another great resource for choosing the best seafood is the Monterey Bay Aquarium’s Seafood Watch, which has guides to print and an app for your phone, so you can always have the info you need to make the best seafood choice.
These guides consider if the methods of harvest harm the environment, farmed vs. wild-caught populations, any potential for contaminants, and whether or not the species is overfished. Species that are overfished are not considered sustainable, and in my opinion should always be avoided.