After a review of current conceptual models used in nutrition studies, we develop and test a ‘Dietary Change Model’ based on a sample of older rural adults. Predictor variables include socio-demographic, social network, and nutritional risk/support constructs; mediating variables include number of dietary changes attempted and whether the changes are successfully made; and criterion variables focus on psychosocial outcomes. The model is tested on a sample of 298 randomly selected respondents aged 60 years or more residing in five rural communities in Oregon. We find that those most likely to make dietary changes are women, married, and living in smaller households. The social network factors of density, range, and frequency of interaction negatively impact healthy dietary change. Among the most important nutritional support factors to have positive effects on dietary change are having a physician recommend changes in diet, and participating in a community food programme (women only). Successfully changing diet most clearly related to life satisfaction; results of other criterion variables were often complicated by marked gender differences.