25-hydroxy vitamin D level and body mass index in postmenopausal women

Abstract

Background. Deficiency and insufficiency of vitamin D is a pandemic of the 21st century. Obese patients have a lower vitamin D level, but the literature data are contradictory. The purpose of this study is to examine 25(OH)D level depending on body mass index (BMI) in postmenopausal women. Materials and methods. One thousand seven women aged 50–89 years were examined: their mean age was 65.74 ± 8.61 years; mean height — 1.61 ± 0.07 m; mean weight — 70.65 ± 13.50 kg; mean BMI — 27.27 ± 4.86 kg/m2 and mean 25(OH)D le­vels in the blood serum — 26.00 ± 12.00 nmol/l. The patients were divided into the following 6 groups depending on their BMI: group I — 338 women with a normal body weight, group II — 16 persons with an insufficient body weight, group III — 382 individuals with an excessive body weight, group IV — 199 women with class I obesity, group V — 60 persons with class II obesity, and group VI — 12 individuals with class III obesity. Results. Vitamin D deficiency was found in 34.4 % of postmenopausal women, insufficiency — in 31.4 %. 25(OH)D levels were significantly lower in women with class I obesity (23.60 ± 10.24 ng/ml) and class II obesity (22.38 ± 10.34 ng/ml), compared with women who had a normal body mass (28.24 ± 12.99 ng/ml), p = 0.00003. The study results reveal a weak correlation between 25(ОН)D level and BMI (r = 0.15). Conclusions. In women with obesity, BMI significantly influences vitamin D level, and this influence does not depend on the season.

Keywords

• body mass index
• obesity
• vitamin D deficiency and insufficiency
• postmenopausal women
• age