January 21, 2020

Robert W Morton, PhD Candidate

Population Health Research Institute, David Braley Research Institute, Hamilton, ON, Canada, Department of Pathology & Molecular Medicine, McMaster University, Hamilton, ON, Canada

The KT committee is introducing a new format for Knowledge Translation articles with an emphasis on how current research may impact practitioners. This month’s article is written by Robert Morton, PhD candidate, McMaster University.


The global market for dietary supplements is estimated to rise to 278 billion USD by 2024. Indeed, researchers and practitioners may be vulnerable to over-interpretation/application of findings in nutrition research. Therefore, it is important for nutrition researchers and practitioners to maintain scientific rigor in their study designs, methodologies, and interpretations

How the study was done

  • The highlighted article is a product of a discussion that included a panel of experts in nutritional science that took part prior to the Canadian Nutrition Society Thematic Conference – Advances in Nutrition: From Daily Living to High Performance Sport in January 2018. 
  • The article is a commentary published as part of Horizons: a series aimed at discussing important achievements and considerations for future research published in Applied Physiology, Nutrition, and Metabolism
  • The article highlights many challenges that are present within nutrition-related research and offers succinct and thoughtful guidelines for future studies (summarized in Tables 1 and 2 of the article).

What the researchers found

  • The researchers highlight necessary and optional (though encouraged) components for publishing nutrition research.
  • To be considered high-quality, a nutrition research study includes: Discussion of statistical power calculations, subject characteristics, justification for what outcomes the researchers measured, measurement error of the outcomes assessed, how inter-species differences (e.g., mice vs. humans) may affect the efficacy of the intervention
  • Specifically, researchers and practitioners should consider the following questions when evaluating and reading nutrition research: How much of the component(s) of interest did the researchers provide to the participants? I​s there an appropriate comparator group? How was the component made? Who made it? Can the researchers be certain the subjects were compliant? What did the researchers measure and why? What did the researchers not measure? Did the researchers control/assess the subjects’ diet and physical activity level outside of the study? Have the results been replicated by others? Was the study a randomized, double-blinded control trial? Were there individual differences in response to the component(s)? Was there any discussion of adverse effects? Did the researchers include enough subjects to appropriately assess the outcomes? Did the researchers discuss how they determined the sample size? Were there any biochemical/metabolic assessments that may explain a mechanism of action for the component(s)? Was there any mention of sex-specific testing or results? Publishing null findings is also important and should be encouraged by manuscript reviewers and editorial boards.
  • Low-quality nutrition research may result in both practitioners and researchers inappropriately interpreting the effectiveness, practicality, and safety of the findings. It is important for both practitioners and researchers to be mindful of what high-quality research publications should include.


It is important for researchers to maintain a high level of scientific rigor when designing and interpreting results in nutrition research. Here, an expert panel of authors provide a concise summary of considerations for researchers and practitioners to use when designing, implementing, and interpreting nutrition research. In addition, the authors add that as peer reviewers and members of editorial boards, it is important to promote and accept high-quality research with null findings. The article is useful for practitioners to use as a guide when determining the efficacy, safety, and applicability of the results.

Take home message

  • There is a need for high-quality experimental design in nutrition research before practitioners can appropriately apply new findings. 
  • High-quality nutrition research should include discussion of statistical power calculations, subject characteristics, measurement error, inter-species differences, and justification for assessments chose

Ferguson SAH, Eves ND, Roy BD, Hodges GJ, Cheung SS. Effects of mild whole body hypothermia on self-paced exercise performance. J Appl Physiol. 2018; 125: 479-485

Wendy W. Ward, Phillip D. Chilibeck, Elena Comelli, Alison M. Duncan, Stuart M. Philips, Lindsay E. Robinson, Trent Stellingwerf. Research in nutritional supplements and nutraceuticals for health, physical activity, and performance: moving forward. Appl Physiol Nutr Metab 2019, 44(5): 455-460, https://doi.org/10.1139/apnm-2018-0781