Calcium and vitamin D fortified milk reduces bone turnover and improves bone density in postmenopausal women over 1 year.

PURPOSE: In Malaysia, hip fracture incidence is higher in Chinese women than other ethnic groups. This study compared the effects of a high-calcium vitamin D fortified milk with added FOS-inulin versus regular milk over 1 year on aspects of bone health in Chinese postmenopausal women in Malaysia.

METHODS

One-hundred and twenty-one women (mean age 59 (± 4) years) were randomized into two groups: control (n = 60; regular milk, 428 mg calcium per day) or intervention (n = 61; fortified milk at 1200 mg calcium, 96 mg magnesium, 2.4 mg zinc, 15 μg vitamin D and 4 g FOS-inulin per day). At baseline, weeks 12, 24, 36 and 52, parathyroid hormone (PTH), C-Telopeptide of Type I Collagen (CTx-1), Procollagen I Intact N-Terminal propeptide (PINP) and vitamin D levels were assessed. Bone density (BMD) was measured at baseline and week 52 using a GE Lunar iDXA.

RESULTS

Body mass index, lumbar spine and femoral neck BMD did not differ between groups at baseline. Over 52 weeks, mean plasma 25 (OH) D3 levels increased to 74.8 nmol/L (intervention group) or remained at 63.1 nmol/L (control group) (p < 0.001 between groups). PTH levels increased in the control group (p = 0.001). The intervention resulted in a significant suppression of CTx-1 and PINP at p = 0.018 and p = 0.004. Femoral neck BMD remained stable in the intervention group but decreased significantly in the controls, with a borderline treatment effect (p = 0.07).

CONCLUSION

Compared with regular milk, the fortified milk suppressed bone turnover markers and tended to increase femoral neck BMD.