Vitamin D and Insulin Resistance in Metabolic Syndrome

Poor vitamin D status is frequently linked with nearly all elements of the metabolic syndrome. There is insufficient evidence of beneficial effect to recommend vitamin D supplementation as a means of improving insulin resistance. The aim of this study was to determine the relation between vitamin D deficiency and insulin resistance in patients with metabolic syndrome.

Materials and Methods: Ninety patients with metabolic syndrome received 200,000 IU vitamin D intramuscularly every 4 weeks for 12 weeks. Serum 25-hydroxy vitamin D [25(OH)D], fasting blood sugar, Hb A1c, homeostasis model assessment of insulin resistance(HOMA IR), serum lipid profiles anthropometric factors and blood pressure were assessed before and after intervention.

Results: After intervention, Serum 25-hydroxy vitamin D [25(OH)D] concentration increased in all subjects (14.5 ± 2.2 vs. 32 ± 5.5 (P .0001)]. There was a significant decrease of HOMA-IR (3.05 ± 0.34 vs 2.08 ± .25(P=0.003) in patients with vitamin D deficiency before supplementation.

In conclusion vitamin D supplementation improve IR in patients with metabolic syndrome with vit D deficiency. So, vitamin D supplementation based on baseline [25(OH)D] is recommended.