Fish And Health

News reports are currently offering a wealth of both good and bad news about the connection between fish and health. Learn about the benefits and risks of eating fish.

Benefits of Fish and Fish Oil

Fish, especially deep-sea species, are a rich source of omega-3 fatty acids–antioxidants that can supplement almost any healthy diet. American Heart Association (2010) recommends at least two servings of fish per week.

Fish is a lean and excellent source of protein, and it supports cardiovascular health and brain function. In addition, wild caught fish doesn’t have many of the negative elements associated with other meat, including unsaturated fats and chemical residues from factory farming.

Fish oil also provides vitamins E and A, which support eye health, skin health and liver function.

Fish Mercury Levels

Unfortunately, the link between fish and health isn’t always positive. Pollutants in our oceans–especially PCBs and mercury–affect wild and farmed fish populations. Fish mercury levels are highest in larger, older and more predatory fish, since mercury becomes more concentrated as it ascends the food chain.

In the following fish, mercury levels may be high enough to endanger pregnant and nursing women, women who may become pregnant and young children:

  • King mackerel
  • Shark
  • Swordfish
  • Tilefish.

For elderly people, the positive effects of fish far outweigh the dangers of fish mercury intake, so individuals 65 and older shouldn’t avoid fish for this reason.

Wild Versus Farmed Fish

Overfishing has led to serious depletion of wild salmon and tuna populations in recent decades. In response to this concern, fish farming has become widespread. Farming involves raising fish to maturity in an enclosure, which is usually submerged in the sea. While the fish are confined, water flows in and out of their enclosure and mingles with the water of the surrounding area.

Although originally promising, fish farming has become problematic for the environment, as well as for the nutritional value of the farmed fish. Since farmed salmon get little exercise, their meat has fewer omega-3 fatty acids than wild fish and a higher content of unhealthy fats. Their flesh is also grey, so it’s usually dyed pink before being sold.

Fish farms also damage the environment, since the fish are given heavy doses of antibiotics to prevent the spread of disease. Fish waste pollutes the water column surrounding the farm. In addition, parasites and disease agents move easily from the farmed fish to wild fish migrating past them, which can decimate wild populations and defeat the original conservational effort of fish farming.

Fish and Health: A Summary

Most people agree that fish is an excellent nutritional choice, especially with the known benefits of fish oil. However, before you buy, investigate the source of freshwater fish or large, predatory fish like salmon. For your health and the health of the environment, choose the following at least three times a week: wild caught deep sea fish, mercury-low species, and freshwater fish from lakes and rivers with low pollution levels.

Resources

American Heart Association. (2010). Fish, levels of mercury and omega-3 fatty acids. Retrieved September 12, 2010, from http://www.americanheart.org/presenter.jhtml?identifier=3013797

Consumer Reports. (2007). Seafood: Farmed versus wild. Retrieved September 12, 2010, from http://www.consumerreports.org/cro/food/food-safety/animal-feed-and-food/animal-feed-and-the-food-supply-105/seafood-farmed-vs-wild/