Effects of fortified milk consumption on bone health in postmenopausal women : a systematic review

Abstract

Background Osteoporosis is one of the major concerns in postmenopausal women which increase the risk of bone fracture. Osteoporosis reduces the quality of life; increases the medical burden in the society and also the risk of mortality. It has been suggested that bone health can be improved through higher dairy products intake. However, dairy consumption may not be a daily habit in all ethnic groups, especially for Asian. Due to lower estrogen level, there is high possibility of rapid bone loss after menopause especially in the first few years. This is associated with greater risk of osteoporosis and bone fracture. This study investigated the effect of dairy product consumption after menopause.

Aim To investigate whether fortified milk consumption after menopause can bring beneficial effects on bone health in postmenopausal women.

Methodology A systematic review was carried out to identify the clinical randomized controlled trials which investigated short-term (4 weeks to 6 months) or long-term (1.5 years to 3 years) postmenopausal fortified milk supplementation on bone health. Outcome measures including bone biochemical markers, vitamin D status, parathyroid hormone level in blood and also bone mineral density were extracted and analyzed.

Results Over a 20 year period (1995-2015), 11research studies (5 short-term interventions and 6 long-term interventions) were identified in this review. All short-term intervention studies showed that bone biochemical markers were altered after supplementation of calcium fortified milk with/without vitamin D and calcium fortified milk with magnesium. This included lower bone turnover markers of serum C-telopeptide of type 1 collagen (CTX) and procollagen type 1 N terminal propeptide (P1NP) in postmenopausal women. Meanwhile a majority of the long-term studies showed that calcium fortified milk with/without vitamin D supplementation after menopause reduced bone loss when compared to the control group. The findings suggested that fortified milk can improve bone health in postmenopausal women.

Conclusion Both short-term and long-term postmenopausal fortified milk supplementation posed beneficial health effects on bone especially in Asian, by reducing the bone loss and also the risk of osteoporosis in postmenopausal women. The findings of this review suggested that acquiring calcium and vitamin D from fortified milk after menopause may improve bone health. However, the dietary requirement of calcium and long term effect of fortified milk on bone fracture and health related risk should be further investigated.