Abstract: Objectives To describe the 25(OH)D status in Spanish obese postmenopausal women and men ? 50 years, to compare their
results with those of the overweight or normal weight population, and to determine whether differences are observed between
both sexes and with seasonal variation throughout the year.
Patients and Methods We studied 2597 subjects (1826 postmenopausal women and 771 men ? 50 years). Serum concentrations
of 25(OH)D, intact parathyroid hormone (PTH), aminoterminal propeptide of type I collagen (PINP), and C-terminal telopeptide
of type I collagen (CTX) were determined by electrochemiluminiscence (Elecsys 2010, Roche). Bone mineral density (BMD)
was measured by DXA. Participants were divided according to body mass index (BMI) groups (normal ? 20 and < 25 kg/m2,
overweight ? 25 and < 30 kg/m2, or obese ? 30 kg/m2).
Results Obese people had lower serum 25(OH)D values (20.9 ± 8.2 ng/ml) than overweight (23.3 ± 8.8 ng/ml; p < 0.0001) or
normal-weight subjects (24.4 ± 8.9 ng/ml; p < 0.0001). They have also lower levels of both PINP and CTX. In contrast, PTH
concentrations and BDMvalues were higher in obese individuals. When stratifying by sex, the difference in serum concentration
of 25(OH)D remained significant in women, but not in men, persisted throughout the year, and was inversely correlated withBMI
and waist circumference.
Conclusions Despite lower serum 25(OH)D concentrations and higher PTH levels, obese and overweight women have higher
lumbar spine and hip BMD and lower bone remodeling markers than normal weight women, suggesting that low serum
25(OH)D levels do not negatively affect bone health.