SIGNIFICANCE: The incidence of osteoporosis has reached epidemic levels in the United States. Once thought to be a natural part of aging among women, osteoporosis is no longer considered age-dependent. Since osteoporosis often produces no symptoms until a fracture occurs, there are no reliable statistics on how many young women have this disease. Due to the multifactorial nature of osteoporosis, prevention efforts for young women need to include educational interventions about behaviors that impact skeletal growth such as proper nutrition, adequate physical activity, and cautious medication use. The purpose of this study was to determine the impact of an osteoporosis prevention program on osteoporosis risk factor knowledge among college women at a Southern university. DESIGN: An osteoporosis intervention including a mass-media campaign and lecture series was implemented during a six-month period. Pretest and posttest osteoporosis knowledge data were collected through an internet survey. Matched data were collected for 419 women on the intervention campus and 177 women on the control campus. ANCOVA was conducted to determine if there was a difference in osteoporosis risk factor knowledge as a result of the intervention. RESULTS: Knowledge increases for the intervention campus were related to eating a diet high in dark green leafy vegetables, having ones ovaries surgically removed, taking steroids for a long time, and exercising on a regular basis. About 90% of the women on either campus were able to identify dairy product consumption with osteoporosis risk. Additionally, 86% of the women on either campus were able to identify osteoporosis risk with menopause while only 36% of women from either campus were able to accurately identify Caucasian or fair skinned women as being at higher risk for osteoporosis. Furthermore, less than half of the women from either campus could identify having ones ovaries removed as being a risk factor for osteoporosis. However, the results indicated that there was not a significant difference in osteoporosis risk factor knowledge as a result of the intervention (F=2.04, p=.15). Previous osteoporosis education has been effective in helping women understand osteoporosis risk as it is associated with low dairy product consumption yet specific areas of osteoporosis knowledge still need to be emphasized as a means of assisting women in assessing their personal risk and identifying methods of prevention. These areas include the impact of estrogen on bone health (i.e. menopause or ovary removal), being Caucasian or having fair skin, medication impacts on bone health, and heredity. Keyword(s): community-based programs, disease prevention, research