Rats in group 1 received no treatment. Rats in group 2 received daily 100 mg/kg body weight niacin injections. Rats in group 3 received daily 50 mg/kg body weight vitamin C injections. Rats in group 4 received both niacin and vitamin C injections. Blood sugar levels were measured before and after treatment. The results showed that niacin and vitamin C both lowered blood sugar levels in normal rats. Niacin was more effective than vitamin C in lowering blood sugar levels in diabetic rats. The combination of niacin and vitamin C was the most effective in lowering blood sugar levels in diabetic rats.