Yerba Mate and Bone Health: Can Antioxidant Capacity Influence Skeletal Outcomes?

Abstract

Background: Oxidative stress contributes to bone loss, and dietary antioxidants may support skeletal health. This study evaluated the effects of yerba mate (YM) infusion with enhanced antioxidant capacity (AOC; YM+) on skeletal outcomes.

Methods: Female Sprague-Dawley rats (6 weeks old) were randomized into three groups: control (water), YM, and YM+. After 90 days, tibial bone mineral density (BMD), biomechanical strength, histomorphometry, and plasma oxidative stress/antioxidant markers were assessed. Data were analyzed by analysis of variance (p<0.05).

Results: Both YM and YM+ groups showed significantly higher tibial BMD vs. control (YM, +10.1%; YM+, +9.1%; p<0.05). Plasma thiobarbituric acid reactive substances decreased (46% in YM, 55% in YM+), indicating reduced lipid peroxidation. Although YM+ had higher ferric reducing antioxidant power values and total polyphenol content (TPC), skeletal outcomes did not differ between YM and YM+. TPC and alkaline phosphatase (ALP) increased significantly in a dose-dependent manner: TPC (μg/mL gallic acid equivalent): control 456±43.2; YM, 577±45.0; YM+, 634±44.4; ALP (IU/L): 0.201±0.010; 0.265±0.049; 0.321±0.051. Histomorphometry showed no differences in trabecular volume, thickness, number, or separation.

Conclusions: regular YM consumption improved BMD and vertebral mechanical strength. However, increasing AOC did not enhance additional skeletal benefits, indicating that increased AOC did not translate into additional skeletal benefits under the experimental conditions tested. These findings support YM as a potential dietary strategy to promote bone health.