Open Access Open Badges Research

Mis-reporting, previous health status and health status of family may seriously bias the association between food patterns and disease

Agneta Hörnell1*, Anna Winkvist2, Göran Hallmans3, Lars Weinehall4 and Ingegerd Johansson5

Author affiliations

1 Department of Food and Nutrition, Umeå University, Umeå, Sweden

2 Department of Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden

3 Nutrition Research, Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden

4 Epidemiology and Global Health, Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden

5 Cariology, Department of Odontology, Umeå University, Umeå, Sweden

For all author emails, please log on.

Citation and License

Nutrition Journal 2010, 9:48  doi:10.1186/1475-2891-9-48

Published: 30 October 2010



Food pattern analyses are popular tools in the study of associations between diet and health. However, there is a need for further evaluation of this methodology. The aim of the present cross-sectional study was to evaluate the relationship between food pattern groups (FPG) and existing health, and to identify factors influencing this relationship.


The inhabitants of Västerbotten County in northern Sweden are invited to health check-ups when they turn 30, 40, 50, and 60 years of age. The present study includes data collected from almost 60,000 individuals between 1992 and 2005. Associations between FPG (established using K-means cluster analyses) and health were analyzed separately in men and women.


The health status of the participants and their close family and reporting accuracy differed significantly between men and women and among FPG. Crude regression analyses, with the high fat FPG as reference, showed increased risks for several health outcomes for all other FPGs in both sexes. However, when limiting analysis to individuals without previous ill-health and with adequate energy intake reports, most of the risks instead showed a trend towards protective effects.


Food pattern classifications reflect both eating habits and other own and family health related factors, a finding important to remember and to adjust for before singling out the diet as a primary cause for present and future health problems. Appropriate exclusions are suggested to avoid biases and attenuated associations in nutrition epidemiology.