Vitamin D status and its association with metabolic syndrome and cardiometabolic markers in postmenopausal women: a population-based study.

OBJECTIVE: To investigate the association between serum vitamin D levels, metabolic syndrome (MetS), and cardiometabolic markers in postmenopausal women from a population-based sample in Brazil. SUBJECTS AND METHODS: This cross-sectional study included 351 women aged 40 to 64 years with at least 12 months of amenorrhea. Serum 25-hydroxyvitamin D was measured by chemiluminescence and categorized into quartiles. MetS was defined according to the Joint Interim Statement criteria. Anthropometric, blood pressure, lipid profile, insulin, calcium, and phosphorus measures were also assessed. RESULTS: Hypovitaminosis D (vitamin D <30 ng/mL) was observed in 66.4% of participants. Women in the highest quartile (≥31.0 ng/mL) had significantly more favorable metabolic profiles than those in the lowest quartile (<21.0 ng/mL), including lower BMI, waist circumference, insulin, and triglycerides, and higher HDL cholesterol. Vitamin D levels <21.0 ng/mL were associated with a 2.27-fold increased risk of MetS (95% CI: 1.21-4.24; p = 0.010). CONCLUSION: Higher vitamin D levels are associated with more favorable metabolic profiles and a reduced risk of MetS in postmenopausal women. Adequate vitamin D status may play a preventive role in mitigating metabolic alterations during postmenopause.