That perfectly seared piece of fish may look like one of the healthiest choices on the menu, but seafood quality involves much more than appearance. Fish can be an excellent source of protein and omega-3 fatty acids, but certain varieties may also raise concerns about mercury levels, environmental impact, fishing methods, and farming conditions. Understanding what you’re eating and where it comes from can help you make more informed choices.

Large, long-lived fish generally deserve the most caution because they can accumulate higher levels of mercury over time. Species such as bluefin tuna, swordfish, orange roughy, and Chilean sea bass may contain more mercury, while some can also face sustainability concerns depending on how and where they are caught. Farmed seafood can vary too, since shrimp, salmon, tilapia, and catfish may come from farms with very different environmental and production practices.

Fortunately, there are plenty of nutritious seafood alternatives to choose from. Wild Alaskan salmon, Pacific cod, U.S.-caught wild shrimp, mussels, sardines, anchovies, and responsibly farmed trout can provide valuable nutrients while often presenting fewer mercury or sustainability concerns. Seafood guides and reputable sustainability certifications can also be useful when deciding what to buy at the store or order at a restaurant.

Ultimately, choosing seafood thoughtfully can benefit both your health and the oceans. There is no need to avoid seafood altogether, since fish can be an important part of a balanced diet. The goal is simply to choose a variety of lower-mercury options and, whenever possible, select seafood from well-managed fisheries or responsible farms. One meal may not change the future of the oceans, but making thoughtful choices consistently can help support healthier marine ecosystems and more sustainable seafood practices.