ABSTRACT
Background: Smoking is an essential determinant of various diseases. The study is aimed to understand the influence of smoking on serum vitamin D2/D3 levels and serum calcium levels in healthy young/middle-aged men.Methods: Prospective observational study was done among young and middle-aged healthy male smokers in a rural territory care center. Two hundred patients were studied and analyzed, who fulfill the inclusion and exclusion criteria.Results: The prevalence of vitamin D deficiency (25(OH)D <20 ng/ml) was 50.3%. Only 8.8% of the participants had vitamin D sufficiency (25 hydroxyvitamin D ?30 ng/ml). There is a strong correlation between 25(OH)D and smoking in the participants (p<0.001). 25 hydroxyvitamin D level was lower by approximately 4.3 ng/ml (p<0.001) in a smoker compared to a non-smoker among the total participants, this value increased to 9.2 ng/ml in the 40-50y subgroup (p=0.003). A multinomial logistic regression model demonstrated that a young smoker (20-29y) had a 58% increased likelihood of having vitamin D deficiency compared to a non-smoker of the same age group (p=0.041). Irrespective of age and chronicity of smoking, there was a significantly increased level of serum calcium and significant vitamin D2/D3 deficiency in smokers.Conclusion: A high prevalence of vitamin D deficiency was identified in young and middle-aged male smokers, which is not likely to be explained by other confounding lifestyle factors. The depression of the vitamin D-PTH system seen among smokers may represent another potential mechanism for the harmful effects of smoking on the skeleton