Effects of tart cherry juice supplementation on biochemical markers of bone metabolism in women aged 65-80 years

Abstract

Objectives: This study examined the dose-dependent effects of supplementation with a commercially available Montmorency tart cherry juice on biomarkers of bone metabolism in older women.

Methods: Women 65-80 years of age (n=27) were randomly assigned to consume one of two doses of tart cherry juice (8 fl. oz. once or twice per day) for 90 d. Serum at baseline and final visits were assessed for biomarkers of bone formation and resorption, endocrine status, inflammation, and oxidative stress. Other data collected include relevant medical history, anthropometrics, calcium intake, physical activity, dietary intake, and sun exposure. Whole body, right hip, and lumbar spine bone mineral density (BMD) was evaluated at baseline with dual x-ray absorptiometry (DXA). Data were analyzed with paired t-test, Chi square analyses followed by confirmation with Fisher’s exact test for categorical data, and Pearson’s correlation.

Results: Biomarkers of bone resorption (i.e., tartrate resistant acid phosphatase type 5b [TRAcP 5b]) were decreased in the high but not the low dose group from baseline. Markers of bone formation (i.e, bone specific alkaline phosphatase) and bone turnover (i.e., osteocalcin [OCN]) were not different from baseline or between treatment groups. C-reactive protein was negatively correlated with TRAcP 5b (r = -0.32) and TBARS was negatively correlated with OCN (r = -0.30).

Conclusion: Supplementation with the higher dose of tart cherry juice for 90 d decreased biomarkers of bone resorption from baseline, but biomarkers of bone formation and mineralization were unchanged in this cohort of older women. Indicators of inflammation and oxidative stress were also unchanged from baseline. Future studies are needed to determine effect of tart cherry supplementation in forms other than juice and on outcomes such as bone mineral density.