Forskning

August 4, 2011

Dark roast coffee is more effective than light roast coffee in reducing body weight, and in restoring red blood cell vitamin E and glutathione concentrations in healthy volunteers

C Kotyczka et al, Dark roast coffee is more effective than light roast coffee in reducing body weight, and in restoring red blood cell vitamin E and glutathione concentrations in healthy volunteers, Mol Nutr Food Res, 2011, Volume 55.

Recent results from prospective cohort studies have shown that moderate coffee consumption is associated with a reduced risk for diabetes mellitus type II or Alzheimer’s disease. Since reactive oxygen species are believed to be involved in the pathogenesis of these diseases, antioxidants in coffee might contribute to this risk in reduction. These authors aimed at elucidating whether a dark roast coffee beverage, rich in N-methylpyridinium ions and low chlorogenic acids has stronger antioxidant effects on human erythrocytes than a coffee beverage prepared from a light roast with opposite proportions. Following a two week wash-out period, 500mL of the respective coffee brew was administered to 30 subjects daily for 4 weeks. Blood and spot urine samples were collected at the beginning and the end of each intervention. Intake of the dark roast coffee brew most effectively improved the antioxidant status of erythrocytes: superoxide dismutase and glutathione peroxidise activity decreased by 5.8 and 15% respectively. Furthermore, administration of theN-methylpyridinium  rich coffee brew led to a significant body weight reduction  in pre-obese subjects, whereas the chlorogenic rich coffee brew did not.