Non-western migrants and ethnic minority populations in western countries are particularly at risk of vitamin D deficiency due to darker skin color and low sun exposure. The aim of this study was to examine levels of 25-OH vitamin D in patients attending a Danish health clinic for migrants. Patients attending the clinic represent a distinct group of migrants with longstanding, unresolved symptoms and often multiple illnesses. In this retrospective study, data on patient demographics and vitamin D levels were extracted from the medical records of 156 patients attending a Migrant Health Clinic in 2008-2011 who were considered at-risk for low vitamin D, mainly due to symptoms of diffuse pain in the muscles, bones or joints. Over the follow-up period of 1 year, the number of patients with vitamin D below 50 nmol/L decreased from 80 to 56%. The median vitamin D level increased from 27 nmol/L [(interquartile ranges (IQR 14.5-45.0)] at baseline to 45 nmol/L (IQR 26.5-64.5) at follow-up. Patient consultations with a holistic approach and close follow-up can help patients with complex symptoms and language barriers to overcome barriers to treatment and adherence, thus leading to improved levels of vitamin D.