Diabetes Intervention Trial With Vitamin D in Subjects of Nordic and Sub-Indian Ethnicity

Inclusion criteria: 1. Moderate (S-25OHD 25-50 nmol/l) to severe (S-25OHD \< 25 nmol/l) vitamin D deficiency measured at Visit 1. 2. Patients with type 2 diabetes, including drug naïve subjects, subjects using oral anti-diabetic medication and subjects on insulin treatment. All medication must be in stable doses during the 4 week lead-in period. 3. HbA1c \< 11 % at Visit 1. 4. Able to communicate in Norwegian. 5. Men and women ≥ 18 years. 6. Norwegian or South Asian ethnicity. 7. Women of childbearing potential (WOCBP) must be using an adequate method of contraception to avoid pregnancy throughout the study. All WOCBP must have negative serum or urine pregnancy test at enrollment, randomization, titration visit and final study assessment. 8. Antihypertensive medication, lipid lowering drugs, oral contraceptives, hormone replacement therapy, multivitamin supplements and nutritional supplements are allowed if the subjects adhere to the same regimen during the study Exclusion Criteria: 1. Subjects not having type 2 diabetes. 2. SBP ≥ 160 or DBP ≥ 95 at Visit 1. 3. Significant renal disease or chronic renal impairment, GFR\< 30 ml/min. 4. Significant liver disease or ASAT or ALAT \>3x UNL. 5. Malignancy during the last five years. 6. Hypercalcemia at Visit 1. 7. A history of kidney stone disease 8. WOCBP unwilling or unable to use an acceptable method to avoid pregnancy. 9. Pregnant or breastfeeding women. 10. Chronic inflammatory disease in active phase 11. Long term (\>2 weeks) use of corticosteroids last 3 months 12. Mental condition (psychiatric or organic cerebral disease) rendering the subject unable to understand the nature, scope and possible consequences of the study. 13. Drug or alcohol abuse. 14. BMI \> 45 kg/m2 or bariatric surgery (\<5 years). 15. Anemia 16. Cardiovascular disease (myocardial infarction, unstable angina pectoris or stroke) during the last 6 months. 17. Any medical condition that in the judgment of the investigator would jeopardize the subject's safety or evaluation of the study drug for efficacy and safety.