In patients with type 2 diabetes, aged 30–60 years, daily oral intake of lower doses of quercetin (250 mg/day, every 2 weeks for 8 weeks) was sufficient to increase the total antioxidant status and antioxidative defense, although this dose was insufficient to regulate glycemic parameters (fasting blood glucose and serum insulin) [259]. Here, INS is linked to type 2 diabetes mellitus.