Vitamin D supplementation improves the metabolic syndrome risk profile in postmenopausal women.

Objective: This study aimed to evaluate the effect of isolated vitamin D (VD) supplementation on the metabolic syndrome (MetS) risk profile in postmenopausal women.Methods: In this double-blind, placebo-controlled trial, 160 postmenopausal women aged 50-65 years were randomized into two groups: VD group, supplementation with 1000 IU vitamin D3/day (n = 80); or placebo group (n = 80). The intervention time was 9 months, and the women were assessed at baseline and endpoint. Clinical and anthropometric data were collected. Biochemical parameters, including total cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides, glucose, and insulin, were measured. The plasma concentration of 25-hydroxyvitamin D (25(OH)D) was measured by high-performance liquid chromatography.Results: After 9 months, there was a significant increase in the 25(OH)D levels for VD group (+45.4%, p < 0.001), and a decrease (-18.5%, p = 0.049) in the placebo group. In the VD group, a significant reduction was observed in triglycerides (-12.2%, p = 0.001), insulin (-13.7%, p = 0.008), and the homeostasis model assessment of insulin resistance (-17.9%, p = 0.007). In the placebo group, there was an increase in glucose (+6.2%, p = 0.009). Analysis of the risk adjusted for age, time since menopause, and body mass index showed that women supplemented with VD had a lower risk of MetS (odds ratio [OR] 0.42; 95% confidence interval [CI] 0.21-0.83), hypertriglyceridemia (OR 0.43; 95% CI 0.22-0.85), and hyperglycemia (OR 0.23; 95% CI 0.10-0.52) compared to the placebo group (p < 0.05).Conclusions: In postmenopausal women with VD deficiency, isolated supplementation with 1000 IU vitamin D3 for 9 months was associated with a reduction in the MetS risk profile. Women undergoing VD supplementation had a lower risk of MetS, hypertriglyceridemia, and hyperglycemia.

Effect of isolated vitamin D supplementation on bone turnover markers in younger postmenopausal women: a randomized, double-blind, placebo-controlled trial.

Vitamin D (VD) plays an important role in bone mineralization. The present study investigates the effect of VD supplementation alone on bone turnover markers in younger postmenopausal women. It has been shown that VD supplementation in postmenopausal women with hypovitaminosis D is associated with a reduction in bone turnover markers. PURPOSE: The purpose of this study is to evaluate the effect of VD supplementation alone on bone turnover markers in younger postmenopausal women. METHODS: In this double-blind, placebo-controlled trial, 160 women were randomized into the VD group (supplementation with 1000 IU of vitamin D3/day, orally; n = 80) or placebo group (n = 80). Women aged 50-65 years with amenorrhea ≥ 12 months and normal bone mineral density were included. The intervention lasted 9 months, and the participants were assessed at the beginning and end of treatment. Serum levels of total calcium, parathormone (PTH), alkaline phosphatase (AP), and 24-h urine calcium were determined. Serum C-terminal telopeptide of type I collagen (s-CTX) and procollagen type 1 N-terminal propeptide (P1NP) were measured by immunoassay as markers of bone resorption and formation, respectively. Plasma 25-hydroxyvitamin-D [25(OH)D] concentrations were measured by HPLC. Intention-to-treat analysis was performed using ANOVA, Student's t test, Tukey's test, and gamma distribution. RESULTS: Over the period of 9 months, 25(OH)D concentrations increased from 15.0 ± 7.5 to 27.5 ± 10.4 ng/mL (+ 45.4%) in the VD group and decreased from 16.9 ± 6.7 to 13.8 ± 6.0 ng/mL (- 18.5%) in the placebo group (p < 0.001). There was a decrease (- 21.3%) of PTH levels in the VD group with a significant difference between groups at the end of the study (p < 0.001). No significant differences were observed in the other laboratory parameters (total calcium, AP, and calciuria) in either group (p > 0.05). A comparison of bone turnover markers showed a significant reduction in of s-CTX (- 24.2%, p < .0001) and P1NP (- 13.4%, p = 0.003) levels in the VD group. No significant variations in bone turnover markers were observed in the placebo group (s-CTX, - 6.9%, p = 0.092 and P1NP, - 0.6%, p = 0.918). CONCLUSION: In younger postmenopausal women with VD deficiency, isolated supplementation with 1000 IU of vitamin D3 for 9 months is associated with a reduction in bone turnover markers. However, any between-group differences was not observed in bone turnover markers.

Low bone mineral density is associated with breast cancer in postmenopausal women: a case-control study.

OBJECTIVE: To evaluate risk factors for low bone mineral density (BMD) in postmenopausal breast cancer survivors compared with postmenopausal women without breast cancer (controls). METHOD: In this study, 112 breast cancer survivors were compared to 224 women (controls). Inclusion criteria were amenorrhea ≥12 months, age 45-75 years, treated for breast cancer, and metastasis-free for at least 5 years. The control group consisted of women without breast cancer, matched by age and menopause status (in a proportion of 1: 2 as sample calculation). The risk factors for low BMD (osteopenia/osteoporosis) were assessed by interview. BMD was measured by dual-energy X-ray absorptiometry in the lumbar spine (L1-L4) and femoral neck. Logistic regression models (odds ratio, OR) were used to identify factors associated with low BMD. RESULTS: The mean (standard deviation) age of breast cancer survivors was 61.3 (9.7) years, with a mean follow-up of 10.2 (3.9) years. These women had a higher incidence of osteopenia (45.1%) and osteoporosis (22.3%) in the femoral neck than controls (39.3% and 9.0%, respectively) (p = 0.0005). Lumbar spine BMD did not differ between groups (p = 0.332). Univariate analysis adjusted for age and time since menopause revealed that chemotherapy (OR 6.90; 95% confidence interval (CI) 5.57-9.77) was associated with a higher risk of low BMD. Contrarily, regular physical exercise (OR 0.24; 95% CI 0.06-0.98) and a body mass index ≥30 kg/m2 (OR 0.09; 95% CI 0.02-0.37) reduced the risk among breast cancer survivors. CONCLUSION: Postmenopausal breast cancer survivors had a higher incidence of osteopenia and osteoporosis in the femoral neck than women without breast cancer. A history of chemotherapy was a risk factor for low BMD, whereas regular physical activity and high body mass index reduced the risk among breast cancer survivors.

Effect of vitamin D supplementation alone on muscle function in postmenopausal women: a randomized, double-blind, placebo-controlled clinical trial.

UNLABELLED: The present study investigates the effects of vitamin D on muscle function in postmenopausal women. It has been shown that vitamin D supplementation in postmenopausal women with hypovitaminosis D provides significant protective factor against sarcopenia, with significant increases in muscle strength and control of progressive loss of lean mass. INTRODUCTION: We aimed to evaluate the effect of supplementation of vitamin D (VITD) alone on muscle function in younger postmenopausal women. METHODS: In this double-blind, placebo-controlled clinical trial, 160 Brazilian postmenopausal women were randomized into two groups: VITD group consisting of patients receiving vitamin D3 1000 IU/day orally (n = 80) or placebo group (n = 80). Women with amenorrhea for more than 12 months and age 50-65 years, with a history of falls (previous 12 months), were included. The intervention time was 9 months, with assessments at two points, start and end. Lean mass was estimated by total-body dual-energy X-ray absorptiometry (DXA) and muscle strength by handgrip strength and chair rising test. The plasma concentrations of 25-hydroxyvitamin D [25(OH)D] were measured by high-performance liquid chromatography (HPLC). Statistical analysis was by intention to treat (ITT), using ANOVA, Student's t test, and Tukey's test. RESULTS: After 9 months, average values of 25(OH)D increased from 15.0 ± 7.5 to 27.5 ± 10.4 ng/ml (+45.4%) in the VITD group and decreased from 16.9 ± 6.7 to 13.8 ± 6.0 ng/ml (-18.5%) in the placebo group (p < 0.001). In the VITD group, there was significant increase in muscle strength (+25.3%) of the lower limbs by chair rising test (p = 0.036). In women in the placebo group, there was considerable loss (-6.8%) in the lean mass (p = 0.030). CONCLUSION: The supplementation of vitamin D alone in postmenopausal women provided significant protective factor against the occurrence of sarcopenia, with significant increases in muscle strength and control of progressive loss of lean mass.