Nutrition in Greenland – A first glance

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Last month I landed in Nuuk, Greenland full of excitement to get started on our dietary study examining a traditional Inuit diet vs a westernized diet on blood sugar and other cardiovascular health markers in the Greenland Inuit population.

As almost everyone landing in Greenland for the first time, the first thing you notice is the stunning nature which is everywhere and breathtaking. I heard about it and was told to expect something special, but it is really something you should experience in person. Incredible.

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However, as someone with a special interest in nutrition, the foods and dietary culture are also of special interest. So one of the first things, after landing and getting settled in our AirBnB, was to visit the local supermarkets. As always, a top attraction for someone with a nutrition background. One of the things you obviously notice (and somewhat expect) is the large assortment of fish, seafood and sea mammals (such as whale and seal) and also local meats such as reindeer and musk ox. However, it is also evident that a lot of imported foods have found their way here – as exemplified with the cereal aisle. What was also striking, but not surprising, was that the price of fresh fruits and vegetables is 4-6 times more expensive compared to Denmark. No wonder this is probably not a stable food at the family dinners.

The trip to the supermarkets gave the first indication of why this population has experienced a rapid increase in obesity and type 2 diabetes prevalence since transitioning from a traditional hunter-gatherer way of living.

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The second indication came when I tried out the local cafés and eating places. First thing I noticed was the big selection of ice coffee with various taste, caramel, ice cream and just loads of whipped cream in general. Apparently, ice coffee is still delicious even if its -10 °C outside… Besides this people also add a substantial amount of sugar to their coffee (we are not just talking one or two scoops). This explained why there is also a separate point just for sugar added to hot drinks in our dietary assessment method, something I found a bit strange to start with. This coffee often comes with cakes with cream. A lot of cream. While I agree that you need something to keep you warm up here, even I found that there is such a thing as too much whipped cream…

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As part of my interest in nutrition, I also enjoy food and trying out local specialties and fine dining. For our Easter dinner, my girlfriend and I tried out Sarfalik where I got to try out the musk soup, reindeer filet and lumpfish roe (aka caviar of the north). An amazing experience to try out the local cuisine at the highest level. This really gave an impression on how one could use the local foods for creating healthy dishes – something that is very central for our dietary study.

When experiencing the cold weather one can understand why the traditional diet of the Inuit was very high fat, high protein as you would want a high fat intake to get enough calories for surviving the winters. Together with the high level of physical activity in the traditional hunter-gather society, this makes a lot of sense. However, in modern societies where physical activity levels are also dropping and simple carbohydrate intake is increasing this does seem to be a recipe for the rapid increase in obesity and type 2 diabetes prevalence.

Obviously, Nuuk is not typical of all of Greenland but it does home a substantial amount of the total population. From a nutritional perspective, there seems to be quite some room for improvement, but also a very high potential for including local foods in a healthy Greenlandic diet. Hopefully, our new research project can uncover some of the potentials of using local foods.

New Project – Sustainable European food systems using microorganisms – the SIMBA Project

SIMBA project

I’m happy to present another new project, SIMBA, not too long after introducing the Greenland Inuit dietary intervention study.

In a recent press release, the overall aim of the project was nicely presented. “SIMBA is a project funded by the European Union that will explore the potential of using microorganisms in plants and animals to improve food security and promote sustainable food production. This is to tackle the growing challenge of supplying food to a growing global population amidst the climate change crisis, through innovative activities around food systems using microorganisms.”

The research in this project is structured around studying microbiome applications in food systems to achieve sustainable innovative solutions for the growing demand for food and for agricultural production around the world. What I’m involved in is a minor part of the larger project. Here we are to test a product that lives up to the above description. Since this involves a company, I cannot reveal too much about the product yet, but this will involve conducting a human intervention study, which I look forward to beginning in Autumn 2019.

As the world population increases and the global climate is changing, we need to find suitable solutions for the supply of food so that it will not become a problem in the future. Worldwide, the demand for food and for agricultural produce is predicted to increase by up to 70% by 2050. Thus, there is an urgent need to improve and be innovative in our food production systems, which needs to meet this increasing demand for food. Here we hope that the SIMBA project will show the potential of microorganisms in this process.

You can follow the project on twitter @SIMBAproject_EU or follow my blog for specific updates on my little part of this huge project.

New Project – The Greenland Inuit diet intervention

Nuuk_city_below_SermitsiaqI’m happy to announce that I’m working on a new project which is centered around a dietary intervention study in Greenland. The overall objective of the study is to investigate a traditional Inuit diet compared to a westernized diet in Greenland Inuit. The reason we are examining this is that the lifestyle of Inuit in Greenland is undergoing a transition from a fisher-hunter society, with a physically active lifestyle and a diet based on the food available from the natural environment, to a westernized society. Parallel to this, a rapid increase in the prevalence of lifestyle diseases such as type 2 diabetes and obesity has been observed[1]. What we are especially interested in is whether switching to a more traditional Inuit diet could improve glycemic control and thus prevent the development of type 2 diabetes.

Studies of Greenland Inuit before the 1980s found a low prevalence of type 2 diabetes compared to Western populations, however, recent population studies in Greenland have found a higher prevalence of pre-diabetes and type 2 diabetes[2,3]. This might in part be explained by the transition in lifestyle, but in addition, a genetic variant increasing the susceptibility to type 2 diabetes have been found to be prevalent in the Greenland Inuit [4], thus further increasing their risk of type 2 diabetes. Therefore, the objective of our study is also to assess whether this gene modifies the effect of following a traditional Inuit diet.

What is a traditional Inuit diet? This is of course hard to examine but multiple studies have tried to assess this in Greenland throughout the last 100 years. They have found that the traditional food of the Greenland Inuit included sea mammals, fish, seafood, and to a lesser degree terrestrial animals and game birds. The sea mammals include walrus, seal meat and blubber, dried whale meat and skin. Fish are local and include halibut, cod, char, salmon and trout, and seafood such as mussels, shrimps, or crab. The terrestrial animals and game birds include lamb, caribou, musk ox, hare, guillemot, eider duck, and eggs from these birds[5–8]. This result is the traditional Inuit diet being higher in fat and protein and lower in carbohydrate compared to a westernized/Danish diet. We have designed the traditional western diet so that it will contain meat from chicken, cow, and pig, as well as having a high amount of cereal products, bread, pasta and rice (carbohydrate).

The study is designed to be a 4-week cross-over intervention study, meaning that each participant has to follow both dietary interventions for 4 weeks in a random order. The study is expected to provide relevant information in relation to whether diet has a role in preventing type 2 diabetes in Greenland and also whether this might be dependent on which genes you have. We have obtained ethical approval for the project and we are currently working on getting all the practical stuff in order so we can begin recruiting participants. The project will start in Nuuk this April, fingers crossed.

The study was initiated by Marit Eika Jørgensen, Lotte Lauritzen and I. The project is a collaboration between researchers at the University of Copenhagen, Steno Diabetes Center Copenhagen, University of Southern Denmark and University of Greenland. It is funded by The Novo Nordisk Foundation who plays no role in the design, methods, data management and analysis or in the decision to publish the results of the study.

References

[1]         Hansen JC, Deutch B, Odland JØ. Dietary transition and contaminants in the Arctic: emphasis on Greenland. Int J Circumpolar Health 2008;67:1–98. doi:10.1080/22423982.2007.11864604.

[2]         Jørgensen ME, Bjeregaard P, Borch-Johnsen K. Diabetes and impaired glucose tolerance among the inuit population of Greenland. Diabetes Care 2002;25:1766–71.

[3]         Jørgensen ME, Borch-Johnsen K, Witte DR, et al. Diabetes in Greenland and its relationship with urbanization. Diabet Med 2012;29:755–60. doi:10.1111/j.1464-5491.2011.03527.x.

[4]         Moltke I, Grarup N, Jørgensen ME, et al. A common Greenlandic TBC1D4 variant confers muscle insulin resistance and type 2 diabetes. Nature 2014;512:190–3. doi:10.1038/nature13425.

[5]         Bjerregaard P, Jeppesen C. Inuit dietary patterns in modern Greenland. Int J Circumpolar Health 2010;69:13–24.

[6]         Deutch B, Dyerberg J, Pedersen HS, et al. Traditional and modern Greenlandic food — Dietary composition, nutrients and contaminants. Sci Total Environ 2007;384:106–19. doi:10.1016/j.scitotenv.2007.05.042.

[7]         Bang HO, Dyerberg J, Hjøorne N. The composition of food consumed by Greenland Eskimos. Acta Med Scand 1976;200:69–73.

[8]         Jeppesen C, Bjerregaard P, Jørgensen ME. Dietary patterns in Greenland and their relationship with type 2 diabetes mellitus and glucose intolerance. Public Health Nutr 2014;17:462–70. doi:10.1017/S136898001300013X.

Should you take folate supplements to reduce the risk of type 2 diabetes?

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I recently published an article in the American Journal of Clinical Nutrition[1], which is kind of a big deal for me since this is one of the first articles where I really feel ownership of the idea. One of my main research interests and what I also did my PhD work on is one-carbon metabolism (yes, nerd alert big time). Basically, this is a pathway centered around folate designed to transfer carbon units for all kinds of biological processes, so if things go wrong here it has a major impact on the whole system. This is partly why inhibitors (blockers) of this pathway are widely used as antibiotics and chemotherapeutics[2]. I could (and probably will) write multiple blog posts on this fascinating and complex biological system, but for now, I will tell you a bit more about the new study.

Actually, this study began with me doing the literature review for my PhD thesis where I wanted to cover pretty much all intervention studies with nutrients related to one-carbon metabolism (I soon realized that this was impossible in the timeframe I had, but did a fair job and ended up with 539 references)[3]. I did cover quite a lot of folate studies and thought that it was strange that no one had noticed the marked decreases in insulin resistance (Insulin and HOMA-IR) values, so I asked my supervisor how hard it was to do a meta-analysis of them. “Easy”, she replied; should have known better. All of the work started in spring 2016 and has finally been published in the American Journal of Clinical Nutrition – almost 3 years later. This tells you something about the speed of science sometimes. Of course, I did not do all the work by myself and have to give a big shout out to especially the last author Jane for providing some much-needed structure and a more clinical angle on the discussion.

The findings in the study were quite interesting as we found that folate supplementation lowered fasting insulin and HOMA-IR indicating that subjects taking folate were less insulin resistant (better of) compared to a control (placebo) group. Another funny finding was that changes in homocysteine were linked to clear changes in both fasting glucose and glycated hemoglobin (HbA1c), and also tended to be associated with changes in insulin and HOMA-IR. Homocysteine is a molecule that is linked with detrimental health outcomes (here insulin resistance), and homocysteine is lowered by folic acid supplementation, which is hypothesized to be a benefit for health. So long story short, we found that the more you can lower homocysteine the larger improvements we see on insulin resistance. This would normally mean that we would also lower the risk of type 2 diabetes… However, we did not find many studies examining the effect on type 2 diabetes (only 2) and overall this did not show marked effects on risk – probably due to the limited number of studies and the modest (if any) effect.  Disappointing… That would have been a really good story.

So, should you then take an extra vitamin pill with folic acid to prevent type 2 diabetes? Well, no. First of all the improvements in insulin resistance was not translated into a clear reduction in risk of type 2 diabetes. Meaning that we cannot see clear effects on the disease we were hypothesizing to prevent. Furthermore, there are some concerns around potential increased risk of cancer and thus uncritically supplementing with folate cannot at present be recommended[4](https://hawcproject.org/assessment/public/). However, our results are still interesting since there might be some remarkable prospects for people already at high risk of developing type 2 diabetes or have type 2 diabetes, with regards to cardiovascular risk (stroke). One very large study has shown that for people with high plasma glucose values or diabetes have a marked reduction (34%) in stroke risk when receiving folic acid[5]. This link between folic acid, type 2 diabetes, and stroke might explain some of the large differences earlier studies of folic acid supplementation found with regards to CVD risk reduction. Thus, as always, more research is needed. Moreover, folate is just one of the components of one-carbon metabolism and the balance/optimal functioning of this pathway depends upon a number of nutrients including other B-vitamins such as B12 [6]. And this is what I spend much of my research time on and untangling this complex link between folate and disease is probably going to keep me busy for a while…

References

[1]         Lind MV, Lauritzen L, Kristensen M, et al. Effect of folate supplementation on insulin sensitivity and type 2 diabetes: a meta-analysis of randomized controlled trials. Am J Clin Nutr 2019. doi:10.1093/ajcn/nqy234.

[2]         Ducker GS, Rabinowitz JD. One-Carbon Metabolism in Health and Disease. Cell Metab 2017;25:27–42. doi:10.1016/j.cmet.2016.08.009.

[3]         Lind MV. The role of diet in one-carbon metabolism and epigenetics, a metabolic syndrome perspective. University of Copenhagen, Faculty of Science, Department of Nutrition, Exercise and Sports, 2016. PhD thesis.

[4]         House AA, Eliasziw M, Cattran DC, et al. Effect of B-Vitamin Therapy on Progression of Diabetic Nephropathy. JAMA 2010;303:1603. doi:10.1001/jama.2010.490.

[5]         Xu RB, Kong X, Xu BP, et al. Longitudinal association between fasting blood glucose concentrations and first stroke in hypertensive adults in China: effect of folic acid intervention. Am J Clin Nutr 2017;105:564–70. doi:10.3945/ajcn.116.145656.

[6]         Paul L, Selhub J. Interaction between excess folate and low vitamin B12 status. Mol Aspects Med 2017;53:43–7. doi:10.1016/j.mam.2016.11.004.

Measuring diet without asking – can we rely on biomarkers as our only source of information?

biomarkers as diet measurement

Recently I was asked if I would do a short article for the magazine BestPractice – general practitioners in Denmark mostly read it. I was going to cover a subject called dietary biomarkers and risk of type 2 diabetes which I found quite remarkable that general practitioners could find interesting.  Anyway, I chose to accept the challenge and tried to cover this with an example of our own research where we did an assessment of dietary intake without relying on people to report their diet – How you ask? (Or at least I hope the general practitioners ask that and don’t turn the page thinking that this is anything but interesting!)

Well, this was based on an article I co-authored with my former supervisor and good colleagues at Chalmers University of Technology and University of Gothenburg, Sweden.  Otto (the first author) deserves most of the credit for this one since he developed the awesome method used for analysis of the samples, as well as did a lot of statistics work and writing to make this happen. The study was published in American Journal of Clinical Nutrition (2017) and was called “Biomarkers of food intake and nutrient status are associated with glucose tolerance status and development of type 2 diabetes in older Swedish women” (link to the original study)[1].

The idea was that we had a cohort of 64-year-old women who only had blood samples taken, with no dietary assessment. Could we really find out what they ate simply using biomarkers in a blood sample?

What is a biomarker?

Well, it can be almost any type of molecule, which is related to the body that reflects some kind of biological condition or state. For example, anything you can measure in blood, urine, faecal, saliva, hair, adipose tissue, semen, teardrop, nose drip, earwax or other biological fluid or tissue you can get your hands on (and who doesn’t like to get their hands on lots and lots of earwax?)[2]. Sometimes people even use the term on other bodily measurements such as waist circumference, limp length or other more exotic anthropometric measurements as biomarkers [3]. However, most often it is a biological molecule found in body fluid or tissue.

In our case, we measured a wide range of molecules present in a blood sample to try to assess markers related to dietary intake using a really cool method on a very expensive machine[4]. E.g., we tried to assess whether you ate a lot of whole grain, fish, meat or bananas from a blood sample (unfortunately, we were not able to cover the last one otherwise you would have already heard about it in some newspaper or blog stating: “Bananas cure diabetes”).

So, what did we find? Well, if I simplify the findings a bit we found that markers of beef intake (β-alanine) were higher in women with type 2 diabetes and impaired glucose tolerance (on the way to type 2 diabetes) while markers of wholegrain wheat and rye (alkylresorcinols), as well as fatty fish (eicosapentaenoic acid, EPA) and vitamin E status (α-tocopherol), were lower. We also found that a higher fish intake (3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid, CMPF) and vitamin E status (α-tocopherol) were associated with a lower risk of developing type 2 diabetes over a 5-year period.

So, can we rely on biomarkers as our only source of information for dietary assessment? Well, in my honest opinion, no, at least not yet. There is great potential in using such advanced methods for gathering complex biomarker information regarding dietary intake [5](shamelessly citing myself), but for now the current methods do not cover enough dietary markers to cover the entire diet sufficiently. Furthermore, there are other limitations and barriers to overcome related to how far back they cover dietary intake or how specific such markers can be… But that will be the topic for another blog post 😉 Thank you for reading along – feel free to leave a comment.

References

[1]         Savolainen O, Lind MV, Bergström G, et al. Biomarkers of food intake and nutrient status are associated with glucose tolerance status and development of type 2 diabetes in older Swedish women. Am J Clin Nutr 2017;106. doi:10.3945/ajcn.117.152850.

[2]         Biomarkers Definitions Working Group. Biomarkers and surrogate endpoints: Preferred definitions and conceptual framework. Clin Pharmacol Ther 2001;69:89–95. doi:10.1067/mcp.2001.113989.

[3]         Gunnell D. Commentary: Can adult anthropometry be used as a ‘biomarker’ for prenatal and childhood exposures? Int J Epidemiol 2002;31:390–4. doi:10.1093/ije/31.2.390.

[4]         Savolainen OI, Sandberg A-S, Ross AB. A Simultaneous Metabolic Profiling and Quantitative Multimetabolite Metabolomic Method for Human Plasma Using Gas-Chromatography Tandem Mass Spectrometry. J Proteome Res 2015. doi:10.1021/acs.jproteome.5b00790.

[5]         Lind MV, Savolainen OI, Ross AB. The use of mass spectrometry for analysing metabolite biomarkers in epidemiology: methodological and statistical considerations for application to large numbers of biological samples. Eur J Epidemiol 2016;31. doi:10.1007/s10654-016-0166-2.