The Nordic Nutrition Recommendations 2022 – structure and rationale of qualified systematic reviews

  • Erik Kristoffer Arnesen Department of Nutrition, University of Oslo, Norway
  • Jacob Juel Christensen Department of Nutrition, University of Oslo, and Norwegian National Advisory Unit on Familial Hypercholesterolemia, Oslo University Hospital, Oslo, Norway
  • Rikke Andersen National Food Institute, Technical University of Denmark (DTU), Kgs. Lyngby, Denmark
  • Hanna Eneroth The Swedish Food Agency, Uppsala, Sweden
  • Maijaliisa Erkkola Department of Food and Nutrition, University of Helsinki, Helsinki, Finland
  • Anne Høyer The Norwegian Directorate of Health, Oslo, Norway
  • Eva Warensjö Lemming The Swedish Food Agency, Uppsala, Sweden
  • Helle Margrete Meltzer Department of Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
  • Þórhallur Ingi Þórhallsson School of Health Sciences, University of Iceland, Reykjavík, Iceland
  • Inga Þórsdóttir School of Health Sciences, University of Iceland, Reykjavík, Iceland
  • Ursula Schwab Department of Medicine, Endocrinology and Clinical Nutrition, Kuopio University Hospital, and Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio Campus, Kuopio, Finland
  • Ellen Trolle National Food Institute, Technical University of Denmark (DTU), Kgs. Lyngby, Denmark
  • Rune Blomhoff Department of Nutrition, University of Oslo; The Norwegian Directorate of Health, Oslo, and Division of Cancer Medicine, Oslo University Hospital, Oslo, Norway
Keywords: Dietary reference values, systematic reviews, national food and health authorities, Nordic countries, Baltics, evidence-based nutrition, nutrient recommendations, causal relationships, food-based dietary guidelines


Background: Qualified systematic reviews (SRs) will form the main basis for evaluating causal effects of nutrients or food groups on health outcomes in the sixth edition of Nordic Nutrition Recommendations to be published in 2022 (NNR2022).

Objective: To describe rationale and structure of SRs used in NNR2022. Design: The SR methodologies of the previous edition of NNR were used as a starting point. Methodologies of recent SRs commissioned by leading national food and health authorities or international food and health organizations were examined and scrutinized. Methodologies for developing SRs were agreed by the NNR2022 Committee in a consensus-driven process.

Results: Qualified SRs will be developed by a cross-disciplinary group of experts and reported according to the requirements of the EQUATOR network. A number of additional requirements must also be fulfilled, including 1) a clearly stated set of objectives and research questions with pre-defined eligibility criteria for the studies, 2) an explicit, reproducible methodology, 3) a systematic search that attempts to identify all studies that would meet the eligibility criteria, 4) an assessment of the validity of the findings of the included studies through an assessment of ‘risk of bias’ of the studies, 5) a systematic presentation and synthesis of the characteristics and findings of the included studies, and 6) a grading of the overall evidence. The complete definition and requirements of a qualified SR are described.

Discussion: Most SRs published in scientific journals do not fulfill all criteria of the qualified SRs in the NNR2022 project. This article discusses the structure and rationale for requirements of qualified SRs in NNR2022. National food and health authorities have only recently begun to use qualified SRs as a basis for nutrition recommendations.

Conclusion: Qualified SRs will be used to inform dietary reference values (DRVs) and food-based dietary guidelines (FBDGs) in the NNR2022 project.


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How to Cite
Arnesen, E. K., Juel Christensen, J., Andersen, R., Eneroth, H., Erkkola, M., Høyer, A., Warensjö Lemming, E., Meltzer, H. M., Þórhallsson, Þórhallur I., Þórsdóttir, I., Schwab, U., Trolle, E., & Blomhoff, R. (2020). The Nordic Nutrition Recommendations 2022 – structure and rationale of qualified systematic reviews. Food & Nutrition Research, 64.
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