Preliminary reports indicate the influence of oxidative stress and interleukins, particularly TGF-beta1, in maintenance of bone mass. This study was designed to determine any possible variations of cellular lipid peroxidation, the total antioxidant power, and concentration of TGF-beta1 in blood and saliva of osteoporotic subjects in comparison to healthy people. Blood and saliva samples of 22 osteoporotic women and 22 age-matched healthy women were collected. Samples were analyzed for thiobarbituric acid-reactive substances (TBARS) as a marker of lipid peroxidation, ferric reducing ability (total antioxidant power, TAP), and concentration of TGF-beta1. The blood and saliva TAP (mean +/- SD) of osteoporotic subjects was significantly lower than that of healthy controls (606.65 +/- 119.13 vs. 665.64 +/- 63.73 mmol/L and 560.43 +/- 84.70 vs. 612.05 +/- 81.5, respectively). Blood and saliva TBARS (mean +/- SD) of osteoporotic subjects were significantly higher than those of healthy controls (0.30 +/- 0.04 vs. 0.26 +/- 0.04 and 0.23 +/- 0.03 vs. 0.16 +/- 0.04 micromol/L, respectively). Concentrations of TGF-beta1 (mean +/- SD) in plasma and saliva of osteoporotic subjects were not different in comparison to healthy subjects. Results indicate that persons with osteoporosis have an increased oxidative stress that is not accompanied by changes in TGF-beta1 levels. Use of supplementary antioxidants in osteoporotic patients may be helpful.