Practical limitations to a positive deviance approach for identifying dietary patterns compatible with the reduction of cancer risk

Abstract

The positive deviance (PD) approach seeks to devise and promote health-promoting practices identified within the most successful member of a society. The World Cancer Research Fund and the American Institute for Cancer Research (WCRF/AICR) recommendations indicate the need for specific dietary behaviours, which may be considered impractical. Thus, it is important to demonstrate ways in which these dietary practices have been achieved from concordant individuals. The present study aimed to assess the feasibility of constructing healthy eating guides in four international settings. Adult participants from the Netherlands (n = 1052), Scotland (n = 849), Mexico (n = 790) and Guatemala (n = 873) enrolled in an international diet survey project. Participants with inadequate diets and current smokers were excluded from the analysis. Concordance with selected WCRF/AICR individual guideline components related to diet and lifestyle were evaluated. A selection of participants was made towards making a set of 14 rotating menus for a cancer-prevention healthy-eating guide. Overall concordance with the WCRF/AICR recommendations was low in all four nations and no participants with an ideal behaviour were found. The selection of candidates for constructing 14 daily menus for a single national guide identified 51, 13 and 12 individuals concordant with 11 of 14 WCRF/AICR recommendation components in Guatemala, Scotland and Mexico, respectively, and 24 individuals concordant with eight of 14 WCRF/AICR components in the Netherlands. The basis for PD guidance for developing dietary recommendations for cancer prevention was strong across all social classes in Guatemala, marginal for Mexico and Scotland, and effectively impossible for the Netherlands.