The objective of this study was to investigate selected factors related to calcium intake and change in calcium intake after an intervention among a sample of 45-54 year old women. The theoretical bases for the research were the Health Belief Model and the health locus of control;A total of 167 women met the criteria and participated in the pre-intervention study. Prior to the intervention, participants completed a five-part questionnaire that provided information on estimates of dietary and supplemental calcium intakes, demographic and lifestyle characteristics, health locus of control, and health beliefs. Immediately following the initial data collection, two-hour informational meetings were held in seven locations in Iowa during Fall, 1995. Approximately six weeks after the intervention, a four-part post-test questionnaire was mailed to the participants. A total of 152 (91% return rate) completed and returned usable questionnaires;All but three participants were white, and all were well educated. According to the multidimensional health locus of control results, this group of participants had relatively high scores for internal locus of control compared to external or chance locus of control. Similarly, the participants' attitudes related to the Health Belief Model were highly positive. Prior to the intervention participants had a mean total calcium intake of 1,423 mg/day that increased to 1,614 mg/day after the intervention. The health belief attitudes significantly predicted supplemental calcium intake both pre- and post-intervention. Chance locus of control was a significant predictor of dietary calcium intake post-intervention. College graduate education level in comparison to the high school graduate level, external locus of control, chance locus of control, and age interacted with peri-menopausal status significantly predicted change in calcium intake pre- to post-intervention. Based on these findings, it is reasonable to conclude that in this study the educational intervention was likely to have been responsible for changing some of the participants' dietary and lifestyle behaviors.