Background and aims Vitamin D has important roles in the regulation of the immune system in Lupus. Seventy percent of lupus patients in Indonesia are experienced hypovitamin D. Curcumin is a natural VDR ligand and has sinergic effect with vitamin D. This study was aimed to determine the effect of adding curcumin on vitamin D supplementation on IFN-γ/IL-4 ratio and IL-17/TGF-β ratio, in SLE patients with hipovitamin D.

Methods This was a randomised controlled trial, double blind study. Forty SLE patients with hypovitamin D were studied, that randomised into two groups: 20 patients (supplementation group) received vitamin D (cholecalciferol 1200 IU daily) with curcumin 20 mg (three times daily); and 20 patients (placebo group) was given vitamin D (cholecalciferol 1200 IU daily) and placebo ( 3 times daily), for 3 months. Cytokines serum levels (IFN-γ, IL-4, IL-17, TGF-β,) were measured by ELISA.

Results After supplementation for 3 months, this study showed that decreased of IFN-γ/IL-4 ratio in the supplementation group was significantly greater than in the placebo group. The decreased of IL-17/TGF-β ratio in the supplementation group was also significantly greater than the placebo group.

Conclusions Adding curcumin on vitamin D supplementation can decrease IFN-γ/IL-4 ratio and IL-17/TGF-β ratio than vitamin D supplementation plus placebo in SLE patients with hipovitamin D.