Determination of Vitamin D Serum Levels in WomenReceiving Vitamin Supplementation: the PERSIANGuilan Cohort Study

Background: vitamin d is a basic nutrient and plays a very crucial role in preventing variousdiseases, so it is known as an indicator of health and survival.objectives: this study was conducted to determine the serum level of vitamin d in womenreceiving vitamin supplementation in persian guilan cohort study (pgcs).materials & methods: in this analytic cross-sectional study that was conducted on persianguilan cohort, 614 subjects from 5633 women aged 35 to 70 years old who were taking vitamin dsupplements were selected through census method. required data were collected in two sectionsof demographic and social characteristics and serum measurement 25-hydroxy vitamin d3 atthree levels of deficient (<10), insufficient (10-20) and sufficient (>20 ng/ml). data analysis wasdone using descriptive and inferential statistics. p<0.05 was considered statistically significant.results: the mean age of people was 50.3±8.7 years, of which 5.2 % of the subjects had vitamin ddeficiency, 29.5% had insufficient serum level and 65.4% subjects with sufficient serum levels. basedon the results, there was a significant relationship between employment status, place of residence andhousing area with vitamin d level (p<0.05), and non-employed persons (p=0.044), living in the city(p=0.002) and a residential house with a higher area (p=0.014) had higher levels of vitamin d. therewas no significant association between serum vitamin d levels with age, body mass index, maritalstatus, alcohol consumption, level of education and how to take vitamin d supplementation.conclusion: in the present study, about one third of vitamin consumers did not have a sufficientserum level despite taking the supplement, so it is expected that the country’s health system, healthofficials, and policymakers pay attention to the education program of optimum consumption aswell as appropriate prescription of vitamin d supplement.