We investigated the relationship between calcium and protein intake and bone loss over a one-year period in 99 early postmenopausal women (1-36 months) aged 51.3 �� 0.31 years. Bone mineral density (g/cm��) of the left hip (total hip, femoral neck, greater trochanter) and lumbar spine (L1-L4) as well as body composition were assessed using dual energy x-ray absorptiometry. Dietary intake of calcium and protein was assessed using a 100-item Block Food Frequency Questionnaire. A physical activity questionnaire was also completed by the subjects to estimate energy expenditure. Paired t-tests revealed that there were no significant differences between baseline and month 12 physical characteristics except for percent fat which increased from 31.99 �� 0.60% to 32.44 �� 0.61% (p=.009). At month 12, bone mineral density decreased significantly at the femoral neck (-0.97 �� 0.31%) and total hip (-0.55 �� 0.24%). The average calcium, protein and calcium to protein ratio intake for the group was 1129.88 �� 46.22mg/day, 57.88 �� 1.93g/day and 20.10 �� 0.71m/g, respectively. Partial correlation analyses showed no significant relationships between change in bone mineral density and average intakes for calcium, protein, or the calcium to protein ratio. After adjusting for hormone replacement status, lean body mass and months post menopause, analysis of covariance revealed that there were no significant differences between groups when intakes of calcium, protein and the calcium to protein ratio were separated into "above recommended" and "below recommended" categories (above or below 1000/1500mg/day, 50g/day, 20:1 mg/g/day, respectively). Our results suggest that consuming adequate amounts of calcium and protein does not appear to significantly slow bone loss after 12 months in early postmenopausal women. / Graduation date: 2003