A Fish Tale

by Ellen Troyer, MT, MA
CEO, Biosyntrx
While Biosyntrx supports a limited amount of omega-3 fatty acid EPA and DHA intake from fish or fish oil, we believe it’s important to discuss the growing amount of science that questions excessive fish oil intake.
Hypothesis Vs. Outcome

An April 14, 2014, meta-analysis-accepted manuscript in the Canadian Journal of Cardiology by George Fodor, MD, PhD, FRCPC, et al. suggests, “A lack of any solid foundation supports the notion that coronary artery disease (CAD) is rare among Greenland Eskimos due to excessively high fish intake. In spite of this lack of foundation, omega-3 fish oil health-promoting and healing properties have captured the attention of the scientific community for the past 40-plus years based on the ‘Eskimo diet.”
According to this article, “thousands of reports on the cardioprotective effects of the ‘Eskimo diet’ have been published in prestigious journals. Currently, nutritional guidelines in Canada, the United States and Europe recommend at least two meals a week containing fish (preferably oily) as part of a healthy diet and, particularly, for the prevention of cardiovascular disease.
“While these recommendations remain in effect, recent randomized long-term trials and systematic reviews report ambiguous or negative results regarding the cardioprotective effects of excessive fish oil and omega-3 fatty acids.
“The contemporary ‘fish story’ started in the 1970s, when two Danish physicians, Hans Olaf Bang and Jorn Dyerberg, visited Greenland to investigate why Eskimos have a reported very low incidence of CAD despite eating large amounts of seal and whale blubber.
“Bang and Dyerberg’s studies were conducted in the area around the town of Umanak, located 500 km north of the Arctic Circle. The town has approximately 1,300 inhabitants, representing approximately 2.3 percent of Greenland’s population, and some settlements are more than 100 miles away from the nearest hospital or health station.”
According to this article, Bang and Dyerberg did not actually examine the cardiovascular status of Greenland Eskimos or those living in and around the small community of Umanak. Instead, they relied mainly on annual reports produced by the chief medical officer in Greenland for the years 1963 through 1967 and 1973 through 1976. Unfortunately, 30 percent of the total population lived in outposts and small settlements where no medical officer was stationed. The death certificates were completed by the nearest medical officer, based on information provided by a medical auxiliary or some other ‘competent’ person.
The first question that Bang and Dyerberg should have asked was, “Is the incidence and / or prevalence of CAD among Greenland Eskimos indeed low?
“In 1940, A. Bertelsen, a Danish doctor who practiced for many years in Greenland, described frequent occurrence of CAD in this Inuit population. His reports, written in Danish and also published in his book with limited circulation, were largely ignored.
“Recent studies have confirmed what Bertelsen ascertained more than 70 years ago, ‘the prevalence of CAD among Eskimos in Greenland and other Inuit populations in Canada and the U.S. is similar or higher compared to that of non-Eskimo / Caucasian populations.’
“The totality of reviewed evidence led these Danish investigators to the conclusion that Eskimos have a similar prevalence of CAD as non-Eskimo populations, they have excessive mortality due to cerebrovascular strokes, and their overall mortality is twice as high as that of non-Eskimo population. Their life expectancy is approximately 10 years shorter than the Danish population.
“The alleged absence of CAD in Greenland Eskimos is a paradoxical finding, given that this is a population mainly sustained on a diet high in animal fat, absence of fruits and vegetables and other important nutrients; in other words, a diet which violated all principles of balanced and heart-healthy nutrition.”
The first question the Biosyntrx science team asks is, “Does what I’m being told or reading make biological sense?”
“Considering the dismal health status of Eskimos, it is remarkable that instead of labeling their diet as dangerous to health, a hypothesis was construed that dietary intake of marine fats prevents CAD and reduces the atherosclerotic burden.
“Why do so many researchers uncritically quote the ‘Eskimo diet’ benefits? Is it misinterpretation of the original finding or an example of confirmation bias?
Although the evidence for excessive fish oil supplementation is unclear, it is estimated that in the U.S. approximately 11 million adults and close to half a million children consume fish oil capsules daily. To date, more than 5,000 papers have been published studying the alleged beneficial properties of omega-3 fatty acids, not to mention the billion dollar industry producing and selling fish oil capsules based on the hypothesis that should have been better questioned from the beginning.”
Man prefers to believe what he prefers to be true. (Francis Bacon)
References:

Fishing for the origins of the “Eskimos and heart disease” story. Facts or wishful thinking? A review. Fodor, George, MD, PhD, FRCPS, et al. April 2014. Canadian Journal of Cardiology.  [abstract]
n-3 fatty acids in patients with multiple cardiovascular risk factors. Risk and Prevention Study Collaborative Group, N Eng J Med. 2013 May 9, 368(19): 1800-8[abstract]
Efficacy of omega-3 fatty acid supplements (eicosapentaenoic acid and docosahexaenoic acid) in the secondary prevention of cardiovascular disease: a meta-analysis of randomized, double-blind, placebo-controlled trials. Kwak SM, Myung SK, et al. Arch Intern Med. 2012 May 14; 172 (9): 686-94.  [abstract]
Revising common beliefs in the management of stable CAD. Ferrai R. National Rev Cardiol 2013 Feb; 10(2): 65-6 [abstract]
Effect of long-chain omega-3 fatty acids and lutein and zeaxanthin supplements on cardiovascular outcomes. Results of the age-related eye disease study 2 (AREDS@) randomized clinical trial. JAMA Intern Med. 2014; 174(5):763-771. [abstract]
Association between Omega-3 fatty acid supplementation and risk of major cardiovascular disease events.  A systematic review and meta-analysis. Rizos E. MD, PhD, Ntzani E. MD, PhD, et al. JAMA September 2012; 308(10): 1024-1033. [full article]
Diets to Prevent Coronary Heart Disease 1957-2013: What Have We Learned?  Dalen M, Devires S the American Journal of Medicine. Dec 31, 2013 [full article]
Get the Facts: Omega-3 Supplements: An Introduction National Center for Complementary and Alternative Medicine NCCAM.