The effects of chromium and vitamin D3 co-supplementation on insulin resistance and tumor necrosis factor-alpha in type 2 diabetes: a randomized placebo-controlled trial

The current study was conducted to assess the effects of simultaneous usage with vitamin D-3 and chromium picolinate (CrPic) supplementations on homeostasis model assessment of insulin resistance (HOMA-IR), fasting blood glucose (FBS), hemoglobin A1c (HbA1c), tumor necrosis factor-alpha (TNF-alpha), and lipid profile in type 2 diabetes mellitus (T2DM). Ninety-two patients with T2DM were randomly allocated to the following 4 groups for 4 months: (I) placebo of vitamin D-3 (n = 23); (II) vitamin D-3 supplement at a dose of 50 000 IU/week (n = 23); (III) CrPic supplement at a dose of 500 mu g/day (n = 23); and (IV) both vitamin D-3 at a dose of 50 000 IU/week and CrPic at a dose of 500 mu g/day (n = 23). HOMA-IR levels increased significantly in groups I and II after the intervention. However, this increase in group I was significantly higher than that in group II after the treatment. HOMA-IR levels were controlled in groups HI and IV during the intervention. TNF-alpha decreased significantly in groups II, III, and IV after the intervention. FBS, HbA1c, and lipid profile did not change significantly in total groups after the intervention. It seems that chromium and vitamin D-3 co-supplementation are probably effective in controlling HOMA-IR by decreasing TNF-alpha in T2DM. Novelty Chromium alone and/or in simultaneous pretreatment with vitamin D-3 is more effective than vitamin D-3 in controlling HOMA-IR in T2DM. Chromium and vitamin D-3 alone and/or in simultaneous pretreatment decrease TNF-alpha in T2DM.