Because foods are consumed in combination, it is difficult in observational studies to
separate the effects of single foods on the development of diseases. A possible way to
examine the combined effect of food intakes is to derive dietary patterns by using
appropriate statistical methods. The objective of this study was to apply a new statistical
method, reduced rank regression (RRR), that is more flexible and powerful than the classic
principal component analysis. RRR can be used efficiently in nutritional epidemiology by …

The recent paper by Hoffmann et al.(1) raises a very important methodological issue in
nutritional epidemiologic research. The investigation of dietary patterns in disease risk
analyses is a necessary step away from the reductionist approach of studying single
nutrients as disease predictors. The suggestion of Hoffmann et al. to substantially improve
the hitherto-applied statistical procedures in dietary pattern analysis by employing a method
that uses an actual data set and prior knowledge about nutrient-disease relations is to be …