Effects of increasing fruit and vegetable intake on bone turnover in postmenopausal osteopenic women

Background and the purpose of the study: Adequate intake of fruits and vegetables could be helpful to prevent major non-communicable diseases . Some nutrients abundant in fruits and vegetables have been shown to affect bone health. In the present study effects of increasing fruit and vegetable intake on bone metabolism in postmenopausal women with osteopenia was evaluated. Methods: In the present clinical trial 45 postmenopausal osteopenic women, between 50-60 years of age participated. Subjects were randomly assigned to intervention or control groups. Subjects in the control group were asked to continue their own dietary patterns and make no changes in their life style. To increase fruit and vegetable intake in the intervention group, they were given 6 extra servings of fruits and vegetables daily. Serum osteocalcin and crosslaps were measured at baseline and after 12 weeks of intervention. Twenty four hrs food recalls were used to assess dietary intake at baseline, during and at the end of the study. Results: Increasing fruit and vegetable intake for 12 weeks reduced serum osteocalcin by 15% and crosslaps by 4%. The reduction was not statistically significant after adjustment for confounding factors. In 9 subjects of the intervention group, both markers of bone metabolism were reduced by 24 %. Baseline serum levels of both bone markers were significantly higher in these subjects.  Conclusion: Increasing fruit and vegetable intake may not reduce bone turnover in postmenopausal osteopenic women, but it may be effective for those who are at higher risk of bone fracture because of higher bone turnover.