There are many great benefits to eating fish. They are a good source of lean protein and are high in nutrients and omega 3 fatty acids, which have documented benefits for the heart. However, there is an ugly side to eating some types of fish such as bluefin tuna, which is popular in sushi dishes. Fishing practices are depleting the bluefin population. According to the Monterey Bay Aquarium's Seafood WATCH program, "the Atlantic population has declined by 90% since 1970." Bluefin tuna contain dangerously high levels of mercury. So, not only are the fishing practices harmful to the bluefin population, but consuming the fish can be harmful to humans. Yet bluefin are being fished faster than they can reproduce. A bit of a paradox you could say!
Its large size is great for the bluefin tuna but not so great for the humans who consume it due to high levels of mercury. Bluefin live longer than other types of tuna and can accumulate more mercury over the lifespan. Why is the bluefin tuna so full of mercury? Mercury occurs naturally in the atmosphere but much of what is in the ocean comes from industrial sources such as run off. The mercury in this run off is converted by bacteria in the water and then absorbed by the fish either through their food or as the water passes over their gills. What are the effects of mercury consumption? According to information provided by the Environmental Defense Fund, eating mercury-contaminated fish can lead to cancer as well as birth defects and can “severely impact a child’s growth”. Fortunately, there are many sustainable alternatives to fish such as the bluefin. In fact, the Monterey Bay Aquarium's Seafood WATCH program provides information on healthy and sustainable fish options. They have a handy pocket guide detailing the best and worst fish options. There’s even an app for your iPhone so you can make healthy, environmentally sustainable choices when you are out. The link to the Seafood WATCH program is: http://www.montereybayaquarium.org/cr/seafoodwatch.aspx
More information about seafood and your health can also be found: http://www.edf.org/page.cfm?tagID=1521