Aim: To investigate correlation of vitamin B12 with obesity insulin resistance, metabolic syndrome.
Methods: The cross-sectional and primary care-based study was carried out. Anthropometric, blood pressure measurements and bioelectric impedance analysis (BIA) were recorded. Vitamin B12, folic acid, hemogram, insulin, ferritin, iron, total iron binding capacity and other biochemical tests were assayed. The subjects were grouped as obesity, overweight, control, metabolic syndrome (MetS) and insulin resistance (IR). Correlation of vitamin B12 with body mass index (BMI), IR, age, and BIA was evaluated.
Results: The study enrolled 976 patients (obesity: 414, overweight: 212, and control: 351). The mean age in groups of obesity, overweight and control were 35.9 ± 8.7, 28.9 ± 6.3 and 33.1 ± 8.7, respectively (p = 0.142). Vitamin B12 level was significantly lower in patients with obesity and overweight than healthy individuals (178.9 ± 25.2; 219.8 ± 78.5, and 328.5 ± 120.5, p less than 0.001, respectively). Vitamin B12 level was lower in patients with MetS (+/-) and IR (+/-), but insignificant (p = 0.075 and 0.058, respectively). Significant and negative correlation was observed between vitamin B12 and BMI (r =-0.221, p=0.001). No significant difference was observed between obese male and female patients (247.8 ± 89.1 versus 235.5 ± 89.3 pg/mL, respectively, p=0.090).
Conclusion: Low Vitamin B12 level was associated with obesity and overweight, but not with insulin resistance, metabolic syndrome and gender. Vitamin B12 was negatively correlated only with body mass index.