The Food and Agriculture Organization of the United Nations (FAO) and World Health Organization (WHO) recently published a new document that weighs the food safety risks against the nutritional benefits of fish consumption, considering the latest scientific evidence.
The last FAO/WHO expert consultation on the risks and benefits of fish consumption took place in 2010. To provide new scientific evidence, the experts conducted five literature reviews, focusing on the health benefits of fish consumption; toxic effects from dioxins and dioxin-like polychlorinated biphenyls (dl-PCBs) in fish; toxic effects from methylmercury in fish; the role of selenium in relation to the health effects of methylmercury; and occurrence data for methylmercury, dioxins, and dl-PCBs in fish and fish products.
Fish is an important source of nutrients and micronutrients like protein, fatty acids, vitamin A, vitamin D, vitamin B12, iodine, iron, selenium, and zinc. Consumption of fish has been linked to potential health benefits like reduced risk of cardiovascular disease, lower risk of stroke, protective neurological effects, and healthy fetal development.
At the same time, fish may contain harmful contaminants due to their ubiquitous presence in the environment, with dioxins and dl-PCBs and methylmercury of specific concern.
Based on the evidence, FAO/WHO found that farmed fish typically have lower levels of dioxins, dl-PCBs, and methylmercury than wild-caught fish, although the difference between farmed freshwater fish and farmed saltwater fish was negligible.
Additionally, shellfish showed lower levels of dioxins and dl-PCBs than finfish, and farmed shellfish had less contaminants than wild-caught shellfish.