 - people who have used vitamin D supplements in last 3 months, having chronic renal disease , GI disease, Hepatobilliary diseases, hematological disorders, hypo- or hyperthyroidism, treatment with orlistat or sibutramine for weight loss, pregnancy and lactation, treatment with insulin or Thiazolidinediones, Smokers,sever change in regular diet and life style,change in type and dosage of regular medication s 