Quercetin's effect in reducing disease risk markers

Researchers in a Journal of the American Dietetic Association report investigated quercetin as an antioxidative and anti-inflammatory for the potential to lower disease risk factors. They evaluated the effect of quercetin, vitamin C, and niacin supplements (500 mg quercetin, 125 mg vitamin C, and 5 mg niacin; 1,000 mg quercetin, 250 mg vitamin C, and 10 mg niacin), on disease risk factors in a large group of community adults varying widely in age and body mass index. Subjects were randomized into one of three groups (placebo, Q-500, or Q-1,000) and ingested supplements for 12 weeks. Blood samples were taken pre- and postsupplementation, and plasma quercetin, inflammatory markers (ie, C-reactive protein and five cytokines), diagnostic blood chemistries, blood pressure, and blood lipid profiles were measured. A small decrease in mean arterial blood pressure was measured for Q-500 and Q-1,000 groups compared to placebo. A difference in serum total cholesterol was measured between Q-500 and placebo groups, and there was small decrease in high-density lipoprotein cholesterol levels in the Q-1,000 group. Change in inflammatory measures did not differ between groups except for a slight decrease in interleukin-6 for the Q-1,000 group. The researchers concluded that Q-500 or Q-1,000 supplementation for 12 weeks had an influence on reduction of disease risk factors.