One of the most severe complications of diabetes is kidney damage, which ultimately can lead to death. In this study, researchers found that turmeric, the yellow pigment in curry, may protect you from this damage. The study was done on rats exhibiting signs of kidney damage (determined by creatinine levels, urea clearance, presence of proteinuria, lipid peroxidation and other oxidative stress markers).
 
The study concluded that chronic treatment with curcumin significantly attenuated both renal dysfunction and oxidative stress in diabetic rats. These results provide confirmatory evidence of oxidative stress in diabetic nephropathy and point towards the possible anti-oxidative mechanism being responsible for the nephroprotective action of curcumin.
 
Clin Exp Pharmacol Physiol. 2006 Oct;33(10):940-5. Curcumin, the active principle of turmeric (Curcuma longa), ameliorates diabetic nephropathy in rats. Sharma S, Kulkarni SK, Chopra K.