Greenland Eskimos, Diet and Heart Disease

16134290_mWith so much being written lately about the relationship between dietary fats and  heart disease there’s no wonder we may feel a bit disoriented.

Of course we could take the easy way out, and follow main stream recommendations, limit the total amount of fats consumed, and avoid saturated fats and cholesterol.

Eating less animal and dairy fat, fewer eggs, and more polyunsaturated fats (PUFA’s) and monounsaturated fats (MUFA’S) could be the way to go in order to reach good heart health according to the specialists. However, I believe there’s limited scientific evidence that this will help us avoid heart disease. So what should we do?

If we could, it would certainly be helpful to study populations with a very low risk of  heart disease and see what they’re eating. However, the problem is that today such populations are hard to find.

But, what about going back in history and dig up such cultures, because certainly they have existed. While having these thoughts today I recalled reading a wonderful scientific paper published by Danish experts in The American Journal of Clinical Nutrition in September 1975.

What the Past Can Teach Us About Diet and Heart Disease

In 1975 it was already known that there was “an intimate relationship”  between the occurrence of coronary atherosclerosis and blood levels of cholesterol and triglycerides. The Greenland Eskimos were no exception from this rule.  Coronary atherosclerosis and heart disease were almost unknown among them when living in their original cultural environment. Their blood levels of cholesterol and triglycerides were very low. However, Greenland Eskimos living in Denmark at that time had much higher cholesterol and triglyceride levels.

The difference in dietary habits between Eskimos living in Greenland and those living in Denmark was substantial. Those living in Denmark had adapted to a Western diet typical of that time.

Meat was the main source of calories among Eskimos living in Greenland, giving rise to a high intake of proteins, and relatively low intake of carbohydrates. The meat mostly originated from animals living in the sea, therefore the composition of the dietary fats was characterized by their maritime origin. In the daily Eskimo food in Greenland the relative amount of protein calories was approximately two and a half times that of the daily Danish food, whereas the relative amount of carbohydrates was only two-thirds. The relative amount of total fat consumption was similar.

The Danish investigators studied the pattern of fatty acids in the blood of 130 West Greenland Eskimos (WGE) and compared them to 30 Eskimos living in Denmark and 31 Caucasian Danes. Very marked differences were observed between the WGE  and the two other groups. The WGE had generally much higher proportions of palmitic acid (saturated fat), stearic acid (saturated fat), palmitoleic acid (omega-7/MUFA), and eicosapentaenoic acid (omega-3/PUFA) and a markedly lower proportion of linoleic acid (omega-6/PUFA).

It is well known that the fatty acid composition of food is a major determinant of fatty acids measured in the blood. So, the Danish scientists had a problem. The generally accepted concept at that time was that a high consumption of PUFA and the avoidance of saturated fats was the best way to avoid heart disease. But here was a population with almost no heart disease and high blood levels of saturated fats, and very low blood levels of PUFA’s (omega-6).

The authors write:

“Coming to this point it is very difficult to combine the generally accepted concept of the advantage of high intake of polyunsaturated fatty acids in prevention of ischemic heart disease with the present results.  The discrepancy is that a generally higher proportion of polyunsaturated fatty acids was not found in the plasma lipids of Greenland Eskimos. In fact, when combining the fatty acids into only three groups: saturated, monoenes, and polyunsaturated, the saturated group was found to be higher and the polyunsaturated lower in the Greenlandic Eskimos. “

This 38 year old paper is probably not less interesting today than it was when it was first published. It strongly suggests that somewhere along our journey to improve health, we may have chosen the wrong path. Furthermore the paper is highly interesting because it was one of the first to highlight a possible relationship between omega-3 consumption and heart disease.

Two years after the publication of this paper, the first dietary guidelines for Americans were released. I assume the Greenland Eskimos would have recommended a different version of that. They would have emphasized that a diet rich in proteins, saturated fats, and omega-3 appears to cut the risk of heart disease. I wonder whether the guideline writers were aware of the Greenland Eskimo experience, or whether they just thought it wouldn’t apply to Americans.

Comments

  1. says

    I actually didn’t know of this study but I’m glad they made the distinction between WGE and Eskimos living in Denmark. The health status of Eskimos living in Denmark is horrible and my best guess is that more than half of them are alcoholics.
    Another important point is that the Eskimos lived of completely fresh, (more or less) non-polluted food and in a non-polluted environment. I know much of that has changed now but back then they were almost completely isolated.

    Even though this is an old study it just highlights what Stefansson found 50 years earlier. First by living with the inuits and later by living of protein and fat in New York.

    • Robert says

      I think Hemming may have hit the nail on the head. Excellent observations that few people notice when he mentioned a non polluted environment. I too studied the traditional Greenland Eskimos and observed Greenland’s remarkable absence of industry.

  2. Richard Mjödstånka says

    There’s tons evidence pointing that the idea of Eskimo’ having low rates of CHD is a complete myth. Ancel Keys wrote about the Masai & Eskimo already back in 1975 refuting the whole nonsense (Coronary Heart Disease – The Global Picture; Keys, Atherosclerosis 22, 1975). At the time when diet-heart studies were launched there were only few hundreds Inuits who lived the traditional lifestyle and very few of them knew their own age. Based on the observations by Danish pathologist prior the Diet-Heart era, CHD was rampant among the Greenland Eskimo’s considering the very low life expectancy of these people. According to the anecdotal data by Danish medical experts, the Eskimo’s appeared physically much older than their real age would have suggested. Some Inuits may have had lower cholesterol due to wide-scale exposure to parasites. Parasites may alter the lipid metabolism of the host as has been documented in the literature.

    Moreover, in 1904, Bertelsen proved the existence of cancer in the native Inuit, diagnosing a case of breast cancer. During the following decades researchers documented that the existence of cancer was exceedingly common among the Inuit despite their relatively short life expectancy. Consistent with Bertelsen’s findings, an Inuit predating western contact who was mummified in approximately 1475, 450km north of the Arctic Circle was shown to have evidence of cancer, likely of the breast. It has also been documented that numerous preserved pre-contact Inuit who were mummified dating all the way back to 1,500 years ago had a severe degree of atherosclerosis, osteoporosis, and osteoarthritis, consistent with studies of Inuit living in the 20th century. Other evidence of poor health among the pre-contact Inuit includes iron deficiency anemia, trauma, infection, dental pathology, and children with downs syndrome and Perthes disease.

    http://onlinelibrary.wiley.com/doi/10.1002/1097-0142(196902)23:2%3C468::AID-CNCR2820230225%3E3.0.CO;2-9/pdf
    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1036622/pdf/medhist00046-0118b.pdf
    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC325106/pdf/thij00043-0014.pdf

    In 1940, based on years of clinical practice and reviewing medical reports, Bertelsen who is considered the father of Greenland epidemiology stated in regards to the mortality patterns amongst the Greenland Inuit that:
    .
    “..arteriosclerosis and degeneration of the myocardium are quite common conditions among the Inuit, in particular considering the low mean age of the population”

    Low incidence of cardiovascular disease among the Inuit—what is the evidence?
    http://www.atherosclerosis-journal.com/article/S0021-9150(02)00364-7/abstract.

    • Doc´s opinion says

      Richard. Several publications have shown that Inuits from Alaska, Canada an Greenland have substantially lower mortality from ischemic heart disease (IHD) than the non-native populations of Alaska, Southern Canada and Denmark.

      Here is an overview of cardiovascular risk factors in Inuits of Greenland, published 1997. The main conclusion was: In spite of an increase westernization of the Greenlander´s lifestyle and high prevalence of several cardivascular risk factors, mortality from IHD is still low.

      • Richard Mjödstånka says

        Doc,

        yes, there’s is conflicting information around the Inuits (Bjerregaard et al 2003). However, to answer your original question, yes: the people who drafted the dietary guidelines knew the Inuits. This is what Keys wrote (1975):

        ”The fact is that nothing is really known about the incidence of atherosclerosis and coronary heart disease among Eskimos. According to Ehrström, arteriosclerosis is common among them, reaching an incidence of 29% in North Greenland, but the evidence is dubious, particularly in regard to atherosclerotic heart disease. In any case we could not expect a high incidence of coronary heart disease among primitive Eskimos because few of them attain an age when they would be likely victim of the disease. The majority of Eskimos no longer eat a high-fat diet, and of those who adhere to the old way of life probably not more than a total of 100 or so men are beyond the age of 50, though estimates are difficult in a widely dispersed population who do not know their own ages and are notorious for appearing far older than their years.”

        As we can clearly see based on my material, it’s a fact that Danish pathologists, in plural form, observed Inuits to have lot of CHD already prior the golden age of diet-heart research. Whether these observations were reliable is obviously a chapter of its own.

        The Inuits carried parasites which obviously confuses lot of things here.
        http://www.ncbi.nlm.nih.gov/pubmed/20320248

        Here’s study that may interest you, Doc. A study that looked directly the carotid artery thickness and consumption of dietary fats.

        Consumption of omega-3 fatty acids is not associated with a reduction in carotid atherosclerosis: the Genetics of Coronary Artery Disease in Alaska Natives study

        “Dietary intake of omega-3 FAs in a moderate-to-high range does not appear to be associated with reduced plaque, but is negatively associated with IMT.The presence and extent of carotid atherosclerosis among Eskimos is higher with increasing consumption of saturated FAs”

        http://www.ncbi.nlm.nih.gov/pubmed/18054937

      • Mie says

        Axel, as you can see from Richard’s post, the data is both scarce and conflicting.

        Furthermore, I’d like to strongly point out that making statements like these ones that you made above:

        “It strongly suggests that somewhere along our journey to improve health, we may have chosen the wrong path.”

        and

        “They would have emphasized that a diet rich in proteins, saturated fats, and omega-3 appears to cut the risk of heart disease.”

        on the basis of selected ecological data is, simply put, totally unfounded.

        Axel, c’mon: you should know better. What about e.g. the natives throughout the world who eat a diet VERY different from that of the Inuit (that is, very high carb, ultra-low safa) and fare brilliantly, with very little CVD to show for? Doesn’t that suggest that we should’ve chosen YET another, very different path?

        Or could it be that all this ecological data amounts to NOTHING compared to evidence of higher quality? You know the hierarchy of evidence/scientific studies, right?

      • Doc´s opinion says

        You´re right Mie. Dietary guidelines should be based on real scientific data. Do you believe they currently are? You are right about my statements. They´re speculative and I guess intended to provoke thoughts and discussions. Of course I don´t have an access to the truth, no more than you do.

      • Mie says

        “Dietary guidelines should be based on real scientific data. Do you believe they currently are?”

        More or less, yes. Depending, of course, which guidelines you’re referring to, but I’d say that e.g. Harward Public Health School’s guidelines are indeed based on real (TM) scientific data. If you disagree, I’d like to hear why.

        Or if you meant some specific guidelines, perhaps you could be more explicit and explain why.

        P.S. If you’re referring to this “safa case”, it was dealt with SOOOO very extensively earlier in different threads, see e.g. the much-too-long debate between Healthy Longevity and me. To cut a long story short: it’s not about safa being healthy (since there’s no evidence to indicate health benefits as such), but about the limits of reductionist approach vs a more balanced approach with several key elements.

      • Richard Mjödstånka says

        Mie,

        the neo-SFA confusion has its origins among a handful of American epidemiologist who show complete disregard to multiple lines of research and who lack a global scope.

        The fact is that the “reductionist” avoidance against SFA has worked tremendously well in Northern Europe, New Zealand, etc (Pedersen et al 2011). People were not asked to adhere to Mediterranean diet, they were asked to cut down the intake of SFA. It’s a simple, cost-effective, non-confusing advice that has served way above the expectations.

      • Kevin O'Connell says

        Health benefits of safa – how about:
        “A diet enriched in saturated fatty acids effectively reverses alcohol-induced necrosis, inflammation, and fibrosis despite continued alcohol consumption. The therapeutic effects of saturated fatty acids may be explained, at least in part, by reduced endotoxemia and lipid peroxidation….” (Nanji, et al., 1995, 2001)

      • says

        I subscribe to several feed and food industry publications. On occasion, something interesting surfaces that pertains to differences in physiological response to vegetable oils and so-called animal fats. Excerpt from Improving fat digestibility with emulsifiers:

        “Bile salts are natural emulsifiers. The monoglycerides that are formed after hydrolysis of the fat also act as emulsifiers. Nevertheless, the capacity of these natural emulsifiers can be a constraint for fat digestion. Young animals have a limited production of bile salts and therefore fat digestibility is premature in the early stage of life. On the other hand, the characteristics of dietary fat can restrict the digestibility. Fatty acid mixtures with high amounts of free fatty acids lack the formation of monoglycerides and therefore have a lower emulsifying capacity. Long chain unsaturated fatty acids and monoglycerides form micelles promptly, whereas saturated fatty acids have lower ability to form micelles because of the low polarity. These characteristics of the fat explain the difference in digestibility. In general, saturated fatty acids, mostly found in animal fat, are digested less easily compared to unsaturated fatty acids, like in vegetable fat. High levels of free fatty acids also limit the digestibility.” http://www.allaboutfeed.net/Nutrition/Feed-Additives/2013/10/Improving-fat-digestibility-with-emulsifiers-1341436W/?cmpid=NLC|allboutfeed_themed|2013-10-01|Improving_fat_digestibility_with_emulsifiers

      • Mie says

        Kevin, you’re referencing rat studies.

        Return when you’ve got proper clinical evidence on humans and/or prospective cohort studies on people.

      • Mie says

        “Of course I don´t have an access to the truth, no more than you do.”

        Of course not. Nobody has.

        But it’s just that your speculative statements on the basis of ecological data are … Well, they smell of ecological fallacy. And in any way, I fail to see their relevance to adding knowledge in these matters (what constitutes a healthy diet and what doesn’t). We’ve known about the different types of native populations with less CHD (the Inuit or the Pima or etc. etc.) for DECADES! Nutritional research, lipidology, epidemiology etc. etc. have moved countless of miles away from all this, this kind of stuff is straight outta the fifties and sixties. This is because we have extensive clinical and epidemiological evidence – and that should be the focal point. Not the Western Inuit.

        (I’m sorry, I know this sounds rude but I feel I must be blunt since I do respect you and your blog & work. In comparison with earlier stuff, this post seems like you’ve let your standards slide.)

  3. drphods says

    It’s a bit like the Maasai people in the Rift Valley in Africa. I once read that they live on a diet of animal fats and blood and they are very thin and I believe the article I read also said they had much lower cholesterol than a typical American also.

  4. says

    Interesting article! Have read about that study before but did not know that the Eskimos on Greenland had higher levels of satured fats in their blood despite eating animal food from the North Atlantic Ocean that is low in saturated fats (due to the fact that i e a seal or a whale would not be very mobile in about zero degrees Celsius). And if they didn’t eat a lot of carbs… were did all that saturated fat in their blood come from?

    By the way I wrote a blog post about the Sami people in Sweden: http://www.lchf.com/?p=200

    • Doc´s opinion says

      I agree with you Per. Generally it is believed that the Greenland Inuits didn´t consume much saturated fat, below 10% according to this paper. Also the ratio between n-3 PUFA´s and saturated fats was much higher than the traditional western diet.

      Will have a look at your article on the Sami people. Thanks

  5. Mie says

    Ecological studies, please. They’re mostly just … well, somewhat interesting. In the sense that the data is scarce and conflicting and that they cannot tell anything about cause & effect.

    • Richard Mjödstånka says

      Mie,

      these are not really ecologic studies, but just mortality statistics. There’s really no systematic data on the diet of the Inuits to would accompany the statistics. The most famous large scale ecologic study was a prospective cohort study which followed the same individuals for decades. Dietary intakes were carefully measured at the baseline. This is the 7CS. Then we have large scale ecologic studies that look at disease outcomes in a given region or a sub-region, these are compared dietary and chemical analysis (blood pressure and cholesterol, etc), but these studies do not necessarily follow the same individual, but relies on statistical means, dietary stats are just means drawn from a certain region. This is the China Study by Campbell et al.

      All form of evidence must be looked through the lenses of totality of evidence, this means that studies should not be looked in isolation. Based on totality of evidence, we have very easy to accept the findings of the China Study and the 7CS. Based on the Taubesian Inuit premise, we ought be very skeptical, since the alleged findings go against everything we know about diet-heart based on multiple lines of research.

      • Mie says

        “these are not really ecologic studies, but just mortality statistics. There’s really no systematic data on the diet of the Inuits to would accompany the statistics.”

        No, these are ecological studies: no prospective approach, limited on the basis of a certain area/ethnic group, data on certain surrogate markers.

        Based on the totality of the evidence, both Campbell’s popular books and Taubesian dogma suck. They’re based on cherry-picked ideological stance, with blatant disregard for EVERYTHING that doesn’t fit the pre-conceived ideas.

    • Mie says

      And to add about safa & the Inuit: the relative amount of safa in their diet was still significantly lower than among Danes in that period (34% of total fat vs. 53% of total fat). P/S ratios, however, weren’t really that different (0.29 among the Inuit and 0.25 among Danes).

  6. davebrown9 says

    My current thinking on these matters is that a high intake of omega-3 oils accelerates ageing and promotes cancers. http://raypeat.com/articles/articles/fats-degeneration3.shtml So any approach that keeps Intakes of both omega-3s and omega-6s to a safe level will be protective. Low fat diets emphasizing root vegetables and beans automatically do this and are healthy for those who can tolerate them. High fat diets can do this also as long as they do not contain large amounts of separated fats in conjunction with refined carbohydrates. http://rdfeinman.wordpress.com/2012/02/22/saturated-fat-on-your-plate-or-in-your-blood/

  7. KV says

    If anybody out there hasn’t seen the photos taken by Peary ~1900 of “the most northerly human beings on the globe” in west Greenland, here they are:
    https://www.archive.org/stream/northwardovergre01pear#page/478/mode/2up

    The men are very, very lean; but the women aren’t so lean. I don’t see that gender difference in the Kitavans. http://www.staffanlindeberg.com/KitavaPhotos.html Maybe the Eskimo women spend much more time indoors.

    I think these kinds of studies are interesting, though they might deserve a standard disclaimer at the top containing the reservations about not necessarily being able to draw conclusions.

    Speaking of which, some writers point to the high rates of osteoporosis in the Eskimos as evidence that high protein consumption leeches calcium from bones in order to counteract the resulting acidity. If that’s not true (I know that Paleos generally say it isn’t true) , then what other possible mechanisms would there be?

    • Hemming says

      Stefansson mentioned that about the women too. I don’t remember him having any specific rationale for it. He did say that they didn’t look fat or chubby but that it looked like a racial trait. I’m not sure if you can make the argument that it was simply necessary for the women to carry some fat for pregnancies in the cold environment.

Let me know what you think!