Milk basic protein increases bone mineral density and improves bone metabolism in healthy young women

Effect of milk basic protein on bone metabolism in healthy young women. Introduction Milk has more beneficial effects on bone health than other food sources. Recent in vitro and in vivo studies have shown that milk whey protein, especially its basic protein fraction (milk basic protein, MBP), contains several components capable of promoting bone formation and inhibiting bone resorption. The object of this study was to examine the effect of MBP on the bone mineral density and bone metabolism of healthy young women. Methods Thirty-five healthy young women were randomly assigned to treatment with either placebo or MBP (40 mg per day) for 6 months. The bone mineral density (BMD) of the lumbar vertebrae L2-L4 of each subject was measured by dual-energy X-ray absorptiometry (DXA) at 0 and 6 months of treatment. Serum and urine indexes of bone metabolism were measured at 0, 3 and 6 months. All subjects completed the study in accordance with the protocol. Results The mean rate of gain of lumbar BMD in the MBP group (1.57%) was significantly higher than in the placebo group (0.13%, P=0.042). When compared with the placebo group, urinary cross-linked N-telopeptides of type-I collagen (NTx) were significantly decreased, and serum osteocalcin was significantly increased in the MBP group at 6 months. Conclusion These results suggested that MBP supplemen- tation was effective in increasing BMD in young women and that this increase in BMD may be primarily mediated through the promotion of bone formation and inhibition of bone resorption by MBP supplementation.