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Canadian Journal of Cardiology

“Fishing” for the Origins of the “Eskimos and Heart Disease” Story: Facts or Wishful Thinking?

Published:April 14, 2014DOI:https://doi.org/10.1016/j.cjca.2014.04.007

      Abstract

      During the 1970s, 2 Danish investigators, Bang and Dyerberg, on being informed that the Greenland Eskimos had a low prevalence of coronary artery disease (CAD) set out to study the diet of this population. Bang and Dyerberg described the “Eskimo diet” as consisting of large amounts of seal and whale blubber (ie, fats of animal origin) and suggested that this diet was a key factor in the alleged low incidence of CAD. This was the beginning of a proliferation of studies that focused on the cardioprotective effects of the “Eskimo diet.” In view of data, which accumulated on this topic during the past 40 years, we conducted a review of published literature to examine whether mortality and morbidity due to CAD are indeed lower in Eskimo/Inuit populations compared with their Caucasian counterparts. Most studies found that the Greenland Eskimos and the Canadian and Alaskan Inuit have CAD as often as the non-Eskimo populations. Notably, Bang and Dyerberg's studies from the 1970s did not investigate the prevalence of CAD in this population; however, their reports are still routinely cited as evidence for the cardioprotective effect of the “Eskimo diet.” We discuss the possible motives leading to the misinterpretation of these seminal studies.

      Résumé

      Au cours des années 70, 2 chercheurs danois, Bang et Dyerberg, ayant été informés de la faible prévalence de la coronaropathie (CP) chez les « Esquimaux » du Groenland ont décidé d’étudier le régime alimentaire de cette population. Bang et Dyerberg ont décrit le « régime alimentaire des Esquimaux » comme étant composé d’une grande quantité de lard (c.-à-d. de graisses d’origine animale) de phoque et de baleine et ont montré que ce régime alimentaire était le principal facteur de la faible fréquence présumée de CP. Cela a servi de précurseur à de nombreuses études, qui ont mis l’accent sur les effets cardioprotecteurs du « régime alimentaire des Esquimaux ». Au vu des données ayant été amassées au cours des 40 dernières années, nous avons mené une revue de la littérature existante sur ce sujet pour examiner si la mortalité et la morbidité liées à la CP s’avèrent en effet plus faibles chez les populations « esquimaude » et inuite comparativement à leurs homologues caucasiens. La plupart des études ont montré que les « Esquimaux » du Groenland et les Inuits du Canada et de l’Alaska souffrent aussi fréquemment de CP que les populations non « esquimaudes ». Notamment, les études de Bang et Dyerberg réalisées au cours des années 70 n’ont pas examiné la prévalence de la CP dans cette population. Cependant, leurs rapports sont encore régulièrement cités comme preuves de l’effet cardioprotecteur du « régime alimentaire des Esquimaux ». Nous discutons des motifs pouvant mener à la mauvaise interprétation de ces études fondamentales.
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