Abstract
Aims: To determine the effects of lycopene supplementation on BMD, biochemical bone turnover (BTMs) and oxidative stress markers among postmenopausal women in a randomized controlled intervention study. Methods: A total of 75 healthy postmenopausal women agreed to participate in the study. Inclusion criteria were age of ≥50-65 years, postmenopausal state, independent mobility, and a femoral neck and/or lumbar spine (L1-L4) Tscore values of ≥1.0. All women were on a free diet. Women were excluded if they had cancer or chronic diseases or treatment for metabolic bone disorders or with diseases known to be associated with increased oxidative stress, or treatment/supplementation knowing to affect oxidative stress or bone health. All gave their informed consent for participation in the study. Women were randomized into 3 equal groups to follow a daily lycopene (Lyc-O-mato) supplementation protocol: (1) 30 mg/day (n= 25); (2) 45 mg/day (n=25); and (3) placebo capsules containing 0 mg/day lycopene (n=25). Following a 4-week washout period during which no lycopene-containing foods were consumed, a 12 h fasting blood sample was collected together with a second-void early morning urine samples. Each women was medically examined and data were collected on lifestyle, level of physical activity and submitted a 4-day dietary records. Women were instructed to start taken their supplement of lycopene with meals, while continuing to avoid all other lycopene-containing foods in their daily diet. Further blood and urine samples were collected at 2, 4 and 6 months of supplementation together with their 4-day dietary records. BMD was measured by DXA at baseline and at 6 months following supplementation. Lycopene, total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), antioxidant enzymes, protein thiols, lipid peroxidation and BTMs (s-OC, s-PINP, s-bone ALP, s-CTX, u-NTX and s-TRACP-5b) were determined at baseline and at 2, 4 and 6 months intervals. Results: Repeated measures ANOVA showed that lycopene supplementation for 6 months significantly increased serum lycopene compared to placebo (P<0.001). Lycopene supplementation for 6 months also significantly decreased bone resorption markers studied (P<0.001) with moderate increases in bone formation markers (P<0.05). Lycopene supplementation significantly increased TAS (P<0.001) and decreased TOS (P<0.001); OSI (P<0.001); lipid peroxidation (P<0.001) and protein oxidation (P<0.001) variables as compared with placebo control, respectively. Conclusion: Our findings confirm the positive effects of 6-months lycopene supplementations on decreasing bone resorption markers together with that of oxidative stress variables among postmenopausal women as compared with placebo controls; and thus may be beneficial in decreasing the risk of bone loss and/or osteoporosis.