Abstract:
Objective: To find out the association between obesity and low serum vitamin D concentrations among females.
Materials and Methods: This cross sectional study was conducted in females aged 20-45 years reporting to dietitian and family
OPD of PNS Shifa Hospital from September 2014 to January 2015. Three forty seven females underwent physical examination
for anthropometric data. Weight was measured using weight scale. Height was recorded using wall mounted stadiometer in
erect position without shoes. BMI was calculated by weight in kilogram (kg) divided by height in square meter (m2). Waist
was recorded by placing measuring tape at midpoint of upper border of iliac crest and lower margin of last palpable rib (WHO
STEPS protocol). Serum Vitamin D level was measured by electro-chemiluminiscence immunoassay.
Results: Mean serum vitamin D level was significantly lower among over weight (>18.5-24.9 kg/m2) and obese females(>30
kg/m2) as compared to normal weight (>18.5-24.9kg/m2) and underweight category (< 18.49 kg/m2). Univariate regression
analysis for BMI and age showed every 1 kg/m2 increase in BMI associated with 0.61 nmol/l decrease in serum vitamin D
levels. It also showed that every one year increase in age decreased 0.22 nmol/l of serum vitamin D level. Multivariate regression
analysis was performed to control the effect of age and demonstrated only significant association with BMI. Pearson correlation
showed that serum vitamin D level was inversely related to both BMI and waist circumference
Conclusion: Vitamin D level was low among overweight and obese females and showed an inverse association with BMI and
waist circumference.
