Is the New Nordic Diet the optimal food system for health and environmental sustainability

By Banaz Al-khalidi

Given the public health burden of lifestyle-related diseases, dietary interventions have been studied widely. Successful dietary approaches, such as the Mediterranean and DASH diets, are often limited by the regional food system and cultural adaptation.

The New Nordic Diet (NND) was developed as part of the Danish multidisciplinary OPUS project (1). The NND was designed by gastronomic, nutritional, and environmental specialists to be a culturally sensitive Nordic diet that is palatable, healthy and environmentally sustainable. The average Danish diet (ADD) tends to be low in fruits and veggies, high in animal foods, sugar products and processed foods. The NND is a predominantly plant-based cuisine comprised of locally grown fruits and veggies in season (more berries, cabbage, root vegetables but less tomato and cucumber), whole grains, rapeseed oil, fish and shellfish, high quality meat but less of it, and more organic produce.

The health effects of the NND were compared with the ADD in a cohort of centrally obese adults (2). A “shop model” was used by participants to collect food ad libitum and free of charge. Cooking courses and cookbooks were also provided as part of the study. Despite the ad libitum design, the NND group consumed significantly less energy (- 422 calories/d) than the ADD group and had higher self-evaluated diet satisfaction. Significant weight loss in the NND group was accompanied by greater reductions in anthropometric measures. Aside from weight loss, systolic and diastolic blood pressure, plasma triglyceride, total cholesterol, and VLDL cholesterol were reduced in the NND group. It is also worth noting that CRP (C-reactive protein; inflammatory biomarker) levels decreased in the NND group relative to the ADD group. This is in accordance with previous studies where a plant based diet has been associated with lower levels of inflammatory biomarkers.

Another study evaluated the environmentally sustainable elements of the NND (3). The effects of diet composition, food transportation (local vs imports), and production method (organic vs conventional) were evaluated based on 16 environmental impact categories, including global warming potential, respiratory inorganics, and nature occupation. The socioeconomic impact of choosing NND resulted in 5% reduction in the overall environmental cost of ADD. The reduction in the overall environmental cost increased from 5% to 32% when the effect of NND’s high organic content was discounted (note: the overall environmental cost of ADD was equated to €835/person per year). In other words, the greater reductions in the overall environmental costs were mainly driven by reduced meat consumption but higher quality meat consumption (i.e. less beef and more grass-fed lamb) and few imported commodities. Organic produce unfavorably increased environmental cost associated with inefficient land use.

Similar multidisciplinary projects are needed in other parts of the world to develop evidence-based strategies that are specific to each region, where policy makers could make use of evidence-based strategies to improve environmental policies. Adapting a regional based diet has the potential to protect both health and the environment but future research should assess the long-term potential of food-environment studies.

Links:
1. http://foodoflife.ku.dk/opus/english/about/
2. http://ajcn.nutrition.org/content/99/1/35.short?rss=1
3. http://ajcn.nutrition.org/content/99/5/1117.abstract

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Highlights from the Micronutrient Forum in Africa

By Sheela S. Sinharoy, MPH

The 3rd Micronutrient Forum Global Conference took place from June 2-6, 2014 in Addis Ababa, Ethiopia, with approximately 1,000 attendees and more than 80 sessions. Some of my personal highlights were:

• Lindsay Allen’s talk on biomarkers for vitamin B12. Dr. Allen argued that depending on the biomarker used, vitamin B12 deficiency may be more prevalent than iron deficiency.
• Michael Fenech’s presentations on the exposome, especially the impact of nutrient deficiencies on the integrity of DNA. He has found that the DNA damage from folate deficiency is equivalent to the damage from 10 times the allowable annual exposure to ionizing radiation.
• Daniel Raiten and Bas Kremer’s talks on the importance of a systems biology perspective. It’s good to be reminded of the need for research on nutrient-nutrient interactions and the role of nutrient “clusters” within biological systems.

The most interesting session, however, was the plenary session on the risks and benefits of iron interventions. Many of us know that iron deficiency is the most common nutritional disorder in the world. It is a major cause of anemia but not always the dominant cause. We also know that the main anemia control strategy worldwide is iron supplementation. However, in cases of anemia that are caused by factors other than iron deficiency, iron supplementation can actually be harmful, exacerbating malaria and increasing pathogenic bacteria in the gut. How, then, to determine whether or not iron supplementation is appropriate?

One possible solution came from Sant-Rayn Pasricha, one of the speakers in the plenary, who presented research on the use of the hormone hepcidin to assess iron status. He and his co-authors found that measurement of plasma hepcidin concentrations is useful for detecting iron deficiency and is more sensitive than ferritin. It is also more practical than the current approach, which involves measurements of ferritin, soluble transferrin receptor, and C-reactive protein to assess iron status.

This is of major importance, especially for those of us who work in developing countries where anemia levels are high. In Dr. Pasricha’s sample of children in The Gambia and Tanzania, 61% had anemia, but only 13% had iron deficiency anemia. Under current recommendations, all of the anemic children would be given iron supplementation, even though most of them were not iron deficient. This is not only a poor use of resources but, more importantly, potentially hazardous.

Iron supplementation is normally guided by hemoglobin levels, which measure anemia but not iron deficiency. Is it time to replace hemoglobin testing with hepcidin testing? There is no low-cost assay for hepcidin, so this is not a practical solution in the field just yet. In the meanwhile, it is important to consider the risks of infection and iron overload that can follow from inappropriate supplementation.

The knowledge I obtained at Micronutrient Forum will undoubtedly enrich my work moving forward. As I continue to make my way through articles referenced in various presentations, I am already looking forward to the 4th Micronutrient Forum Global Conference, scheduled for 2016 in Mexico.