While worries about toxic contamination of food fish continue to bedevil different Cree communities in Eeyou Istchee, a recently published study suggests that the health benefits of consuming wild fish far outweigh the risks.
Published in the July issue of the American Journal of Clinical Nutrition, the study was lead by Eric Dewailly at Laval University (Dewailly is also partnered with McMaster University professer Evert Nieboer to conduct a health survey among Ouje-Bougoumou residents this summer). The study examined the effect of beneficial fatty acids found in fish on heart disease among the adult population of the James Bay Cree.
Native communities in Canada, despite other pressing health problems, have lower mortality rates from cardiovascular disease, and the study’s researchers strongly link that phenomenon to the consumption of fish.
“The Cree population must be encouraged to maintain their traditional fish-based diet,” the study’s authors argue, “which may be one of the factors protecting them against mortality from cardiovascular disease.” The study’s data was gathered in 1991 during a Santé Québec Health Survey, which may make the results slightly dated due to the rapid economic and cultural change in Cree communities. Researchers took fish consumption data and blood samples from 917 people aged 18 to 74, and found that the mean intake to be 60 grams of fish (at least on the day before the survey was conducted).
The study looked at the concentrations in test subjects of so-called n3 fatty acids. Also known as fish oil, fatty acids are found mostly in fish, but are contained in other foods as well. Fish oil is the best food source of these fatty acids.
The primary benefit of n3 fish oil is the reduction of platelet activity (blood clotting) and plaque formation, which in turn can prevent heart attacks. Platelets are dot-forming blood cells that prevent excessive bleeding. Overly active platelets, however, may speed the build-up of plaque, a deposit of fatty or fibrous material which narrows a blood vessel wall.
Elevated blood cholesterol also contributes to the acceleration of plaque formation. When plaque narrows an artery it is easier for a blood clot to get stuck in the artery and this can cause a heart attack. Because platelets also form blood clots, this is likely to occur. That’s why it is desirable to reduce platelet activity and why n3 fatty acid, or fish oil, is beneficial.
The fish oil also has the happy side effect of increasing HDL cholesterol in the blood. That’s the good kind of cholesterol that reduces risk of heart attack, as opposed to the life-shortening cholesterol that drenches every potato chip and french fry.
Despite the positive findings, the introduction of non-traditional foods over recent decades may be causing rates of heart disease to increase among the Cree, the study notes. This may be partly accounted for with rising rates of risk factors such as high blood pressure, diabetes, obesity and smoking. But diet is among the most important indicators of risk.
“Traditional eating habits among Cree have changed in response to many factors, such as their settlement in permanent communities, an increase in salaried employment, the growth of modern air transportation, and the increased availability of and access to market foods.” The study also found, perhaps not surprisingly, that consumption of traditional foods increases with age. Younger subjects consumed far more processed foods than their elders. Fish intake also was higher in coastal communities.
The authors also briefly address controversies over mercury poisoning of fish. “News on the presence of mercury in fish has indirectly affected lifestyle and the perception of food quality safety and has been linked to a reduction in fish consumption.” The implication is that concerns over mercury and, by implication, other toxic contaminants may be causing more harm than good. The study didn’t address those risks, however, preferring to emphasize the abundant evidence that traditional foods are central to healthy communities.
“The precontact Indian diet, which comprised wild meat, fish, fat, and vegetation, provided proper amounts of the required nutrients. The Cree of James Bay, as is the case with other peoples of the Canadian North, have adapted their diet to the many changes brought about by contact with the Euro-American culture…. Very little information has been reported on the benefits of fish consumption. Thus, the Cree population must be encouraged to maintain or increase their consumption of traditional foods, ie, fish, which contribute importantly to the intake of n3 fatty acids.”