Addition of milk does not alter the antioxidant activity of black tea

Ann Nutr Metab. 2005 May-Jun;49(3):189-95. doi: 10.1159/000087071. Epub 2005 Jul 13.

Abstract

Tea is a polyphenol-rich beverage like wine and catechins are its chief polyphenols. Catechins have cardio-protective effects as they can scavenge free radicals and inhibit lipid peroxidation. Epidemiological studies indicate an inverse relation between tea consumption and the risk of cardiovascular and other chronic diseases. Addition of milk to black tea has been reported to adversely affect its beneficial effects, but the data are not unequivocal. Therefore, we assessed the effect of the addition of milk to black tea on its ability to modulate oxidative stress and antioxidant status in adult male human volunteers. Although the area under the curve of plasma catechins was lower on the consumption of tea with milk compared to black tea, it did not affect the beneficial effects of black tea on total plasma antioxidant activity, plasma resistance to oxidation induced ex vivo, and decreased plasma and urinary thiobarbituric acid reactive substance levels. The results suggest that addition of milk may not obviate the ability of black tea to modulate the antioxidant status of subjects and that consumption of black tea with/without milk prevents oxidative damage in vivo.

MeSH terms

  • Adult
  • Animals
  • Antioxidants / metabolism*
  • Area Under Curve
  • Biological Availability
  • Catechin / antagonists & inhibitors*
  • Catechin / blood*
  • Free Radical Scavengers
  • Humans
  • Lipid Peroxidation / drug effects
  • Male
  • Middle Aged
  • Milk*
  • Oxidation-Reduction
  • Tea / chemistry*
  • Thiobarbituric Acid Reactive Substances / analysis

Substances

  • Antioxidants
  • Free Radical Scavengers
  • Tea
  • Thiobarbituric Acid Reactive Substances
  • Catechin