Vitamin D supplementation improves SIRT1, Irisin, and glucose indices in overweight or obese type 2 diabetic patients: a double-blind randomized placebo-controlled clinical trial

What this study found

Vitamin D supplementation improved serum 25-(OH)D, SIRT1, irisin, and HbA1c, but did not significantly improve fasting glucose, insulin, or QUICKI. In the vitamin D group, 25-(OH)D rose from 17.24 (7.83) to 38.86 (10.76) ng/ml, SIRT1 from 24.94 (4.38) to 27.90 (5.58) ng/ml, irisin from 18.15 (5.96) to 21.99 (5.93) ng/ml, and HbA1c from 7.51 (0.87)% to 6.76 (0.98)%. The authors concluded that vitamin D may improve type 2 diabetes through increases in SIRT1 and irisin and a reduction in HbA1c. HOMA-IR did not improve; it increased from 5.36 (3.23) to 6.44 (3.73), although the placebo group…

Study & population

This was an 8-week double-blind randomized placebo-controlled clinical trial conducted in overweight or obese adults with type 2 diabetes and vitamin D deficiency.

Intervention

Oral vitamin D pearls were given at 50,000 IU/week for 8 weeks in a double-blind comparison with matching placebo pearls containing oral paraffin.

Key limitation

The trial was short at 8 weeks and had a modest sample size, with only 42 analyzed participants in the active arm.

View full study detailsView sourceOpen PDF