The process of bone remodeling exhibits pronounced diurnal pattern that is important for bone health. A balanced rate of bone resorption is required to maintain bone health, a balance that can be disturbed during the life-cycle to effect net rate of formation (as occurs during growth and development to adulthood) or net resorption (as occurs, for example, during the menopause). Bone turnover is a nutritionally modulated process and the investigators believe a milk-based protein supplement (MBPS) can modulate beneficially the rate of bone resorption over the time period when bone remodeling is most active i.e. late evening/overnight. In this novel approach to the timing of nutrient ingestion, the proposed nutrient intervention seeks to modify (reduce) the rate of bone resorption and promote the rate of bone formation to the benefit of bone health in this at risk population..

Study design:

A block randomised, controlled study among healthy, post-menopausal women with osteopenia receiving a milk-based protein supplement (MBPS) in the evening, or not,(CONTROL) for a period of 24 weeks.

Composition of MBPM - 25g of milk-based proteins + 1000mg dairy-based calcium fortified with 40ug Vit D flavoured and textured. All formulations to be supplied food grade and product tested by Dairygold Co-operative Society, Mitchelstown, Ireland.

Participants:

60 Post-menopausal women with osteopenia as determined by site-specific bone mineral density BMD (DXA) diagnosed and screened by a clinician and for dietary intake of calcium and Vit D by a clinical dietitian.

Inclusion Criteria:

• Post-menopausal women aged 50-70y. Assessed by site-specific BMD to be osteopenic. Assessed by clinical screen to be otherwise healthy and free from other illness or current medication likely to influence the study outcome.

Exclusion Criteria:

• Intolerance to dairy-based food products