In what may be yet another case of eat-this-oh-wait-don’t-eat-this, the safety of several plant-based antioxidants are being called in to question.
Scientists are suggesting more research on the possibility that some plant-based antioxidants–including some commonly touted as healthful and renowned for their cancer-fighting ability–may actually aggravate or cause cancer in people with diabetes. The recommendation was made after a study in which two antioxidants, quercetin and ferulic acid, appeared to aggravate kidney cancer.
The plant-based antioxidants looked at in this study are quercetin, which is abundant in onions and black tea, and ferulic acid, found in corn, tomatoes, and rice bran. Both also are used in a number of herbal remedies and dietary supplements.
The study found that diabetic laboratory rats fed either quercetin or ferulic acid developed more advanced forms of kidney cancer, and concluded the two antioxidants appear to aggravate or possibly cause kidney cancer. “Some researchers believe that quercetin should not be used by healthy people for prevention until it can be shown that quercetin does not itself cause cancer,” the report states. “In this study we report that quercetin aggravated, at least, if not directly caused, kidney cancer in rats,” it adds, suggesting that health agencies like the U. S. Food and Drug Administration should reevaluate the safety of plant-based antioxidants.
Until further studies are performed, it seems prudent to limit intake of these antioxidants to their natural food forms, and to not consume extra doses in the form of remedies or supplements.
The study, “Quercetin and Ferulic Acid Aggravate Renal Carcinoma in Long-Term Diabetic Victims” appears in ACS’ bi-weekly Journal of Agricultural and Food Chemistry.