Effect of dark chocolate on plasma epicatechin levels, DNA resistance to oxidative stress and total antioxidant activity in healthy subjects

Br J Nutr. 2010 Apr;103(7):1008-14. doi: 10.1017/S0007114509992698. Epub 2009 Nov 5.


Dark chocolate (DC) may be cardioprotective by antioxidant properties of flavonoids. We investigated the effect of DC (860 mg polyphenols, of which 58 mg epicatechin) compared with white chocolate (WC; 5 mg polyphenols, undetectable epicatechin) on plasma epicatechin levels, mononuclear blood cells (MNBC) DNA damage and plasma total antioxidant activity (TAA). Twenty healthy subjects followed a balanced diet (55 % of energy from carbohydrates, 30 % from fat and 1 g protein/kg body weight) for 4 weeks. Since the 14th day until the 27th day, they introduced daily 45 g of either WC (n 10) or DC (n 10). Whole experimental period was standardised in antioxidant intake. Blood samples were collected at T(0), after 2 weeks (T(14)), 2 h and 22 h after the first chocolate intake (T(14+2 h) and T(14+22 h)), and at 27th day, before chocolate intake (T(27)), 2 h and 22 h after (T(27+2 h) and T(27+22 h)). Samples, except for T(14+2 h) and T(27+2 h), were fasting collected. Detectable epicatechin levels were observed exclusively 2 h after DC intake (T(14+2 h) = 0.362 (se 0.052) micromol/l and T(27+2 h) = 0.369 (se 0.041) micromol/l); at the same times corresponded lower MNBC DNA damages (T(14+2 h) = - 19.4 (se 3.4) % v. T(14), P < 0.05; T(27+2 h) = - 24 (se 7.4) % v. T(27), P < 0.05; T(14+2 h) v. T(27+2 h), P = 0.7). Both effects were no longer evident after 22 h. No effect was observed on TAA. WC did not affect any variable. DC may transiently improve DNA resistance to oxidative stress, probably for flavonoid kinetics.

Publication types

  • Clinical Trial
  • Comparative Study

MeSH terms

  • Adult
  • Antioxidants / metabolism
  • Antioxidants / pharmacology*
  • Cacao / chemistry*
  • Catechin / blood
  • Catechin / pharmacology*
  • DNA Damage / drug effects*
  • Female
  • Humans
  • Male
  • Oxidative Stress / drug effects*
  • Oxidative Stress / genetics
  • Plant Extracts / blood
  • Plant Extracts / pharmacology*
  • Young Adult


  • Antioxidants
  • Plant Extracts
  • Catechin