Objective: In our study, we aimed to determine vitamin D levels among obese patients registered to Obesity Center and to investigate its relationship with body mass index (BMI).

Methods: The study was conducted in the Obesity Center of Health Sciences University Samsun Training and Research Hospital. Records of 102 patients with BMI> 30 kg/m², 18 years of age and over, admitted to the obesity center between 01.12.2018 and 01.12.2019 were retrospectively analyzed. Serum 25-OH D level<20 ng/ml was accepted as severe insufficiency, 20-30 ng/ml insufficiency, >30 ng/ml proficiency. Mann-Whitney U, Pearson chi-squared and Spearman tests were used in the evaluation of the data. The data were evaluated by the SPSS 22.00 program. p<0.05 was considered significant.

Results: A total of 102 patients participated. The mean age was 48.82±12.09 years. 62.75% of them were female. 24.51% of participants were class 1 obese, 32.35% of participants were class 2 obese, 43.14% of participants were class 3 obese. The prevalance of severe vitamin D insufficiency was 45.10% and insufficiency in 38.24% of the patients. The mean vitamin D levels of the patients registered to the Obesity Center was 13.26±7.74 ng/ml. The mean BMI was 35.26±4.28 kg/m². Serum 25-(OH)D levels were inversely related to BMI. There was a significant relationship between age and BMI (p=0.036).

Conclusion: Vitamin D insufficiency is highly prevalent in obese patients registered to Obesity Center. Serum 25-(OH)D levels were inversely associated with BMI. Obese patients should be evaluated and followed for vitamin D insufficiency.

Keywords: obesity, obesity center, body mass index, vitamin D