Health benefits of fish consumption over-dramatized

Mar 17 2009

The health benefits of fish consumption have been over-dramatized and have put increased pressure on wild fish, according to a new research published in the Canadian Medical Association Journal ( CMAJ ).

In an innovative collaboration, medical scientists from St. Michael's Hospital and the University of Toronto have teamed up with researchers from the University of British Columbia's Fisheries Centre and author Farley Mowat to closely examine the effects of health claims with regard to seafood.

For years, international agencies concerned with health and nutrition have promoted seafood consumption. "Our concern is that fish stocks are under extreme pressure globally and that studies are still urgently required to define precisely who will benefit from fish oil," says Dr. David J. A. Jenkins, a doctor at St. Michael's Hospital and a professor at the University of Toronto Faculty of Medicine's Department of Nutritional Sciences.

"Further, if we decide that fish oil supplementation is necessary for good health, then unicellular sources of 'fish oil' like algae, yeasts, etc, should now be used, as they are in infant formula," adds Dr. Jenkins.

While many studies show healthy benefits of consuming omega-3 fatty acids, found in fish oils, some other studies fail to show significant benefits. But these negative studies are often ignored and the result is that there is increasing demand for seafood by consumers in the developed world, often at the expense of food security in developing nations.

"Governments and industry tell consumers to eat more fish because it is healthy," explains Rashid Sumaila, director of the Fisheries Economics Research Unit at UBC Fisheries Centre and study co-author. "But where do we get these fish? They are increasingly coming from the waters around Africa and other places where food security is a problem."

At best, fish oils are just one factor out of many that may reduce ailments such as heart disease and researchers found that people who do not eat fish, such as vegetarians, are not at increased risk of illness.

Furthermore, dietary recommendations to consume more fish are incompatible with the sustainability of ocean ecosystems, according to a concurrent study recently published in the International Journal of Epidemiology.

"For people in Canada or the US, or in the EU, eating fish is one of many possible options, both in terms of a tasty meal, and in terms of a balanced diet," says UBC fisheries researcher Daniel Pauly. "For many people in developing countries, fish is often their only source of protein. It would be irresponsible for us to 'triage' food sources without verifying that fish oil indeed promotes human health."

Farley Mowat, co-author on this study, adds: "In the immediate future, human beings are going to have to find better ways to live. Our rape and pillage of the environment has to end before it becomes our end. The damage we have already done to life in the oceans is a prime example of our idiocy, and a last warning that we had better change our ways."