The Effect of Vitamin D Supplementation in Type 2 Diabetes

After informed consent, investigators randomized 180 type 2 diabetes into interventiona group (25-hydroxy vitamin d 2000 IU+ elemental calcium 200mg per day) or placebo group (elemental calcium 200mg per day). The participants should control diabetes by oral medications or lifestyle intervention at the intervention period. Investigators exclude the participants who took vitamin D or calcium or anti-osteoporotic drugs. Investigators also exclude renal insufficiency (Cr>1.5 in men or Cr>1.4 in women) or heavy alcoholics.

Investigators followed the participants for 24 weeks. After randomization, investigators checked HbA1c,glucose, calcium, 25-hydroxyvitamin d, AST, ALT,Creatinine, Parathyroid hormone, bone-specific alkaline phosphatase, serum CTX, brachial-ankle pulse wave velocity, central blood pressure, and aortic augmentation index, and precontrast liver computed tomography. Also investigators checked body weight, height, and peripheral blood pressure.

At 12 weeks, investigators checked HbA1c, 25-hydroxy vitamin D, AST, ALT, calcium, and creatinine.

At the end of the study(at 24 weeks), investigators checked HbA1c, glucose, AST, ALT, Creatinine, calcium, bone-specific alkaline phosphatase, serum CTX, brachial-ankle pulse wave velocity, central blood pressure, aortic augmentation index, and precontrast liver computed tomography.

After the study completed, investiators compared the data of interventional groups and placebo groups.

Inclusion criteria

• TYPE 2 DIABETES MELLITUS PATIENTS WHO CONTROL GLUCOSE BY ORAL ANTIBIABETIC DRUGS OR LIFESTYLE ONLY
• DID NOT CHANGE ANTIDIABETIC DRUG BEFORE THE STUDY FOR 2 MONTHS
• normal physical activity
• 30 to 69 years
• >=6.5% OR <8.0% OF HbA1c

Exclusion criteria

• Creatinine>1.5 in men, >1.4 in women
• heavy alcoholics
• who took calcium or vitamin d or anti-osteoporosis drug within 3 months before the study