The Short-Term Effects of Prunes in Preventing Inflammation and Improving Indices of Bone Health in Osteopenic Men
Abstract Objectives Osteoporosis is a public health concern for both women and men. Chronic inflammation contributes to bone loss; therefore, foods rich in antioxidants, such as prunes, are of great interest. Previously, dietary intervention with prunes has been shown to prevent orchidectomy-induced decreases in BMD, microstructure, and biomechanics in male rats; however, there is a need for this to be studied in a clinical setting in adult males. Methods Thirty-five men between the ages of 55 and 80 with moderate bone loss were included. The men were randomized into one of three groups: 100 g prunes daily, 50 g prunes daily, or control group. All three groups also consumed a multivitamin containing 450 mg calcium and 800 IU vitamin D. Serum samples from the baseline and three-month time points were analyzed for biomarkers of bone turnover, inflammation, and oxidative stress. Results After three months, daily consumption of 100 g prunes was associated with a significant decrease in serum concentrations of osteocalcin (P < 0.001). Consumption of 50 g of prunes was associated with significant decreases in systolic blood pressure, and serum osteocalcin concentrations (P = 0.040), and an increase in the OPG: RANKL ratio (P = 0.041). There were also significant decreases in systolic blood pressure, OPG (P = 0.004), RANKL (P = 0.010), and osteocalcin (P = 0.049) in control group. There was a significant group*time effect for changes in OPG (P = 0.019) and the OPG: RANKL ratio (P = 0.029). Conclusions Decreases in osteocalcin indicate a decrease in bone turnover, and a higher OPG: RANKL ratio indicates that more RANKL is bound to OPG, and not to osteoclasts, thus downregulating osteoclast activity. Therefore, regular consumption of either 100 g or 50 g dried plum for three months may make some contributions to bone formation and bone turnover activity, and minimal contribution to decreasing inflammation and improving bone density and quality. Funding Sources USDA/NIFA, California Prune Board, and Shaklee.