Vitamin D deficiency in relation to general and abdominal obesity among high educated adults.

PURPOSE

To assess the association of vitamin D deficiency with general and abdominal obesity among high educated Iranian adults.

METHODS

Current cross-sectional study was done on 500 Iranian professors aged 35 years or more. Complete data on general and abdominal obesity as well as serum 25(OH)D concentrations were available for 352 persons. Obesity was considered as body mass index ≥ 30, and abdominal obesity as waist circumference ≥ 80 cm for women and ≥ 94 cm for men. Furthermore, vitamin D deficiency was defined as serum 25(OH)D < 30 ng/ml.

RESULTS

Mean age of study population was 53.03 ± 7.15 years. Compared with those in the first quartile of serum 25(OH)D, participants in the fourth quartile were less likely to be generally obese (OR 0.46, 65% CI 0.22-0.99). Such finding was also seen even after taking potential confounders into account. Furthermore, we found an inverse association between serum 25(OH)D and abdominal obesity in fully adjusted model (OR 0.44, 95% CI 0.22-0.86). In addition, a significant positive association was found between vitamin D deficiency and obesity; such that after controlling for potential confounders, participants with vitamin D deficiency had 2.16 and 2.04 times greater odds for having general (OR 2.16, 95% CI 1.05-4.45) and abdominal obesity (OR 2.04, 95% CI 1.16-3.60), respectively, than those with normal levels of vitamin D.

CONCLUSION

Serum 25(OH)D concentrations were inversely associated with general and abdominal obesity. In addition, vitamin D deficiency was positively associated with both general and abdominal obesity.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.