I’d like to expand a little on my recent interview for a CNN piece by Elizabeth Landau entitled “Farmed or wild fish: Which is healthier?”

At face value, this question can partialy be answered by comparing the nutritional content in farmed and wild fish and weighing the health benefits of fish consumption against the risks of pollutants present in fish. The Institute of Medicine of the National Academies has expertly covered this topic in Seafood Choices: Balancing Benefits and Risks, and authorities like Dr. Charles Santerre, have produced an excellent seafood consumer guide (Fish for Your Health wallet card) based on Omega-3 fatty acids, mercury and PCBs in fish. These comprehensive benefit-risk analyses and consumer-friendly information are useful and important contributions, though focus solely on human health.

In any discussion of seafood, it is also important to consider the negative impacts of fish farming or wild-caught fishing can have on the environment. These environmental impacts are considered as the basis for progressive fish certification schemes (examples: Friends of the Sea or Marine Stewardship Council) and consumer recommendation lists (example: Monterey Bay Aquarium wallet card) (read more). Sustainability should be an important consumer consideration, though in these certification schemes and consumer guidance materials, human health considerations are often absent.

There is a third perspective endorsed by the Johns Hopkins Center for A Livable Future (CLF) and others, which acknowledges the complex interrelationships among diet, food production, environment and human health. We are inextricably connected to our food systems and the environment, and by treating the natural world with respect – especially in regards to our diet – we can realize long-term health and ecological benefits. Polluting the environment, irresponsible practices in fish farming or overuse of fisheries can hurt humans in ways we may forget or not know to consider. Two examples of these complex linkages for seafood are:

• Human produced environmental pollutants such as persistent organic pollutants (POPs), PCB, PBDEs, dioxins, and methylmercury can concentrate in wild-caught and farmed fish as they eat smaller polluted fish (ex: salmon, Hites et al., 2004). A recent study had linked POPs, at levels present in some farmed Altlantic salmon, with insulin resistance and associated obesity and liver disease in rats (Ruzzin et al., 2009).
• Antibiotic use in fish farming promotes antibiotic-resistant bacteria in fish (Furushita et al., 2003), a phenomenon that mirrors industrial terrestrial food animal production (Aubry-Damon et al., 2004) and is a potential cause of increased community associated antibiotic-resistant infections in humans (Gilchrist et al., 2007).

Connecting food production, the environment, and human health is a daunting task, and requires looking at issues from many angles at once. My complements to the CNN author, Elizabeth Landau, for introducing a range of environmental and food systems topics into her article on seafood, and beginning to explore alternative connections between seafood and public health.

– Dave Love