On the one hand, farmed salmon has more heart-healthy omega-3 fatty acids than wild salmon. On the other hand, it also tends to have much higher levels of chemical contaminants that are known to cause cancer, memory impairment and neurobehavioral changes in children. What's a consumer to do?
In general, a new study shows that the net benefits of eating wild Pacific salmon outweigh those of eating farmed Atlantic salmon, when the risks of chemical contaminants are considered, although there are important regional differences.
Those are the conclusions of Barbara Knuth, Cornell professor of natural resources who specializes in risk management associated with chemical contaminants in fish, and Steven Schwager, Cornell associate professor of biological statistics and computational biology and an expert in sampling design and statistical analysis of comparative data. The two have co-authored a benefit-risk analysis of eating farmed versus wild salmon in the Journal of Nutrition (November, Vol. 135).
"None of us [study authors] argues that the benefits of salmon are not real. But the dirty little secret is that there are risks," said Schwager, noting that even taking into account the risks, the benefits of salmon may be particularly worthwhile for some groups.
"For a middle-aged guy who has had a coronary and doesn't want to have another one, the risks from pollutants are minor ones, and the omega-3 benefits him in a way that far outstrips the relatively minor risks of the pollutants," he said. "But for people who are young -- and they're at risk of lifetime accumulation of pollutants that are carcinogenic -- or pregnant women -- with the risks of birth defects and IQ diminution and other kinds of damage to the fetus -- those risks are great enough that they outweigh the benefits."
Knuth added: "Because we found regional differences in contaminants in farmed salmon, with Chilean salmon showing the lowest levels and European (particularly Scot
Contact: Joseph Schwartz
Cornell University News Service