Research appearing in Acta Pharmacologica Sinica (Sept. 28, 2007; (9): 1422-1428) has shown that black raspberries can prevent tumors in rats. New research looks at the effect raspberries have on humans with respect to cancer biomarkers. The research was presented at the sixth annual conference for the American Association for Cancer Research.

The subjects of the study were 20 men and women with Barrett’s esophagus; a condition that gives the patient between 30% and 40% increased risk for developing esophageal cancer. Men were given 45 g. of freeze-dried black raspberries each day and 32 g. were given to the women.

Isoprostane is chemical marker that can indicate oxidative stress and DNA damage. The chemical has been linked to Barrett’s esophagus and esophageal cancer. Of the subjects who were given the raspberries, 58% had a reduction in isoprostane. A significant percentage of the subjects receiving the raspberries (37%) had an increase in an enzyme (GSTpi) that detoxifies carcinogens.