Abstract
Quantitative nutrition education research assists nutrition educators first, by helping them understand the factors that influence dietary behavior, and second, by providing a systematic method of investigating the most effective methods for influencing dietary behavior to promote health. This paper discusses four broad categories of factors influencing dietary behavior: physiological factors, sociodemographic factors, behavioral and lifestyle factors, and knowledge and attitude factors. Research findings illustrating what can be learned from examination of each of these categories of factors are presented. The need for more unified, theory-based research on factors influencing dietary behavior is discussed and the U.S. Department of Agriculture's Diet and Health Knowledge Survey is presented as a data set that can be used to carry out this type of research. Finally, the advantages of using both qualitative and quantitative research methodologies to investigate methods of influencing dietary behavior are argued.