Risk Factors For Development Of Osteoporosis

Toronto Osteoporosis Prevention Study (TOPS)

In March 1999, the Canadian Institutes of Health Research (formerly the Medical Research Council of Canada) awarded the Osteoporosis Research Program funds to examine the relationship between the following factors and their combined effect on bone mineral density in young women:

• dietary factors (dietary estrogens, dietary calcium)
• diet behaviours
• body composition (percentage fat vs lean body mass)
• menstrual function (subclinical abnormalities)
• exercise

There are 250 healthy women between the ages of 21-38 years enrolled in this study. This two-year study involves an annual bone density assessment and completion of a yearly questionnaire on lifestyle factors and diet. In order to assess menstrual function, participants are also asked to monitor their menstrual cycles by collecting daily saliva samples during 6 menstrual cycles each year. Recruitment has been completed and we anticipate that this study will be completed by summer 2003.

Through this project we hope to increase our understanding of the unique contributions of diet, diet behaviour, physical activity, body composition and menstrual function to the attainment and maintenance of peak bone mass. In doing so, it is hoped that additional modifiable risk factors for osteoporosis will be identified.

Back to Index