title: Lycopene consumption decreases oxidative stress and bone resorption markers in postmenopausal women.
abstract: BACKGROUND
  Oxidative stress induced by reactive oxygen species (ROS) is associated with the risk of osteoporosis, and can be reduced by certain dietary antioxidants. Lycopene is an antioxidant known to decrease the risk of age-related chronic diseases, such as cancer. However, the role of lycopene in osteoporosis has not yet been investigated.
  
  
  METHODS
  In a cross-sectional study, 33 postmenopausal women aged 50-60 years provided seven-day dietary records and blood samples. Serum samples were used to measure serum lycopene, lipid peroxidation, protein thiols, bone alkaline phosphatase (BAP), and cross-linked N-telopeptides of type I collagen (NTx). The serum lycopene per kilogram body weight of the participants was grouped into quartiles and associated with the above serum parameters using one-way ANOVA and the Newman-Keuls post-test.
  
  
  RESULTS
  The results showed that groups with higher lycopene intake, as determined from the dietary records, had higher serum lycopene (p<0.02). A higher serum lycopene was found to be associated with a low NTx (p<0.005). Similarly, groups with higher serum lycopene had lower protein oxidation (p<0.05).
  
  
  CONCLUSIONS
  In conclusion, these results suggest that the dietary antioxidant lycopene reduces oxidative stress and the levels of bone turnover markers in postmenopausal women, and may be beneficial in reducing the risk of osteoporosis.
authors.affiliation: Division of Endocrinology and Metabolism, Department of Medicine, St. Michael's Hospital, Toronto, ON, Canada. leticia.rao@utoronto.ca
authors.forename: L G
authors.initials: LG
authors.lastname: Rao
authors.forename: E S
authors.initials: ES
authors.lastname: Mackinnon
authors.forename: R G
authors.initials: RG
authors.lastname: Josse
authors.forename: T M
authors.initials: TM
authors.lastname: Murray
authors.forename: A
authors.initials: A
authors.lastname: Strauss
authors.forename: A V
authors.initials: AV
authors.lastname: Rao
mesh_terms: D000975:Antioxidants / Q000008:administration & dosage* / Q000378:metabolism; D001823:Body Composition / Q000502:physiology; D001835:Body Weight / Q000502:physiology; D001862:Bone Resorption / Q000517:prevention & control*; D002338:Carotenoids / Q000008:administration & dosage* / Q000097:blood; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003430:Cross-Sectional Studies; D015930:Diet Records; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects; D000077276:Lycopene; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000517:prevention & control; D018384:Oxidative Stress / Q000187:drug effects*
chemical_list: D000975:Antioxidants; D002338:Carotenoids; D000077276:Lycopene