Mercury is a health concern—in excess it can cause neurological issues—but keep in mind that all fish contains traces of this metal, since it’s in our water, notes Tim Fitzgerald, director of impact at the Environmental Defense Fund’s Fishery Solutions Center. “It’s about the dose you’re getting,” he says.
One easy rule of thumb? "If a fish is bigger than you, it probably has a lot of mercury," says Fitzgerald. That's because larger fish (like swordfish and tuna) eat little fish, which drives up their mercury levels even more. Still, there are plenty of safe, low-mercury seafood picks, and as long as you're not frequently eating large portions of high-mercury fish, it's not a major issue.
RELATED: 21 Healthy Seafood Recipes
Turns out, the way fish is raised and caught can also have health implications. You would think that wild-caught would always be the way to go, but that's not the case. While there is concern about the use of chemicals, overcrowding, and disease with farmed fish, farming in closed tanks can be healthy and eco-friendly. "Farmed doesn't inherently mean bad or unsafe or dirty," says Fitzgerald. "Some farms are green and sustainable," while others are bad news.
Despite the scary headlines, we should be eating more seafood, experts say. Fish and shellfish are high-quality proteins, low in saturated fat and calories, and packed with nutrients and necessary fatty acids that help promote heart health.