While there are services and rankings -- even smartphone apps -- to help you decide what to order, researchers say that simple rule of thumb is sufficient.
"If the fish is sustainable, then it is likely to be healthy to eat too," Leah Gerber, a professor and senior sustainability scientist at Arizona State University said.
In a study, Gerber and colleagues brought together the sustainability rankings from several organizations, the health metrics of consumption ranked by various species -- like how much omega-3 fatty acids are found in a specific fish type -- any known contaminant exposure and data from several ecological studies on the relative health of specific species, an ASU release reported Thursday.
"In general, larger longer-lived fish are more likely to have exposure to toxins due to the length of their lives and their place on the food chain," Gerber said. "So you might be best served to stay away from them -- like bluefin tuna or swordfish. Besides they already are overfished."
Safer choices might be Alaskan pollock, Atlantic mackerel or blue king crab, Gerber said.
The researchers say they've developed a seafood database that highlights both the sustainability and health aspect of species.
"We used the database to look for patterns of similarity between ecological and health metrics, and found that in general, choosing healthy seafood also means that you are choosing sustainable seafood," Gerber said.
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