Fermented Milk Products and Bone Health in Postmenopausal Women: A Systematic Review of Randomized Controlled Trials, Prospective Cohorts, and Case-Control Studies.

Milk and milk product consumption is positively associated with bone mineral density (BMD). Emerging evidence suggests that fermented milk products (FMPs) may have specific beneficial effects on skeletal health. We conducted a systematic review and meta-analysis to assess the effect of FMPs on bone health indicators in postmenopausal women given their increased risk for osteoporosis and fragility fractures. Electronic databases were searched for randomized controlled trials (RCTs) and prospective cohort and case-control studies that examined the relation between FMPs and bone health outcomes (fracture incidence, BMD, BMD T-score, and percentage change in bone turnover markers) in postmenopausal women. Two reviewers independently conducted abstract and full-text screenings and data extractions. Risk of bias was assessed using the RoB 2.0 tool and the Newcastle-Ottawa scale for interventional and observational studies. Pooled RRs were obtained using a random-effects model by the DerSimonian-Laird method. Three RCTs, 3 prospective cohorts, and 3 case-control studies met the inclusion criteria. Results of the meta-analysis of 3 cohort studies (n = 102,819) suggest that higher yogurt consumption was associated with reduced hip fracture risk (pooled RR: 0.76; 95% CI: 0.63, 0.92, I2 = 29%), but no difference in hip fracture risk was found between higher and lower cheese consumption (pooled RR: 0.89; 95% CI: 0.73, 1.10, I2 = 0%). Case-control studies revealed that cheese intake had either a null or a protective effect against osteoporosis (BMD T-score ≤-2.5). Daily yogurt or cheese intervention (<2 mo) decreased bone resorption marker concentrations, but had no effect on bone formation markers. In postmenopausal women, of the FMPs studied, only greater yogurt consumption was associated with a reduced risk of hip fracture compared with low or no intake. Daily cheese intake may be associated with higher BMD T-scores, but evidence was limited. Additional and longer-term trials examining these relations are warranted.