Anti-oxidanten in chocolade versterken werking bloedvaten?*

Hier een wetenschappelijk onderzoek waarvan de conclusie wat gekleurd kan zijn.Het onderzoek is grotendeels betaald door de chocolade-industrie met als inzet een nieuw product van Mars. Blijf dus matig met het eten van chocolade.

Flavonoid-Rich Dark Chocolate Improves Endothelial Function and Increases Plasma Epicatechin Concentrations in Healthy Adults

Mary B. Engler, PhD, Marguerite M. Engler, PhD, Chung Y. Chen, PhD, Mary J. Malloy, MD, Amanda Browne, BS, Elisa Y. Chiu, BS, MS, Ho-Kyung Kwak, PhD, Paul Milbury, MS, Steven M. Paul, PhD, Jeffrey Blumberg, PhD, FACN and Michele L. Mietus-Snyder, MD

Laboratory of Cardiovascular Physiology, Department of Physiological Nursing (M.B.E., M.M.E., A.B., E.Y.C., M.L.M.-S.), Boston, Massachusetts
Office of Research (S.M.P.), Boston, Massachusetts
School of Nursing, Cardiovascular Research Institute (M.J.M.), Boston, Massachusetts
School of Medicine, University of California, San Francisco, California, Antioxidant Research Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University (C.Y.C., H.-K.K., P.M., J.B.), Boston, Massachusetts

Address reprint requests to: Dr. Mary B. Engler, University of California, San Francisco, 2 Koret Way, Suite N631, San Francisco, California 94143-0610. E-mail: mary.engler@nursing.ucsf.edu

Background: Dark chocolate derived from the plant (Theobroma cacao) is a rich source of flavonoids. Cardioprotective effects including antioxidant properties, inhibition of platelet activity, and activation of endothelial nitric oxide synthase have been ascribed to the cocoa flavonoids.

Objective: To investigate the effects of flavonoid-rich dark chocolate on endothelial function, measures of oxidative stress, blood lipids, and blood pressure in healthy adult subjects.

Design: The study was a randomized, double-blind, placebo-controlled design conducted over a 2 week period in 21 healthy adult subjects. Subjects were randomly assigned to daily intake of high-flavonoid (213 mg procyanidins, 46 mg epicatechin) or low-flavonoid dark chocolate bars (46 g, 1.6 oz).

Results: High-flavonoid chocolate consumption improved endothelium-dependent flow-mediated dilation (FMD) of the brachial artery (mean change = 1.3 ± 0.7%) as compared to low-flavonoid chocolate consumption (mean change = –0.96 ± 0.5%) (p = 0.024). No significant differences were noted in the resistance to LDL oxidation, total antioxidant capacity, 8-isoprostanes, blood pressure, lipid parameters, body weight or body mass index (BMI) between the two groups. Plasma epicatechin concentrations were markedly increased at 2 weeks in the high-flavonoid group (204.4 ± 18.5 nmol/L, p 0.001) but not in the low-flavonoid group (17.5 ± 9 nmol/L, p = 0.99).

Conclusion: Flavonoid-rich dark chocolate improves endothelial function and is associated with an increase in plasma epicatechin concentrations in healthy adults. No changes in oxidative stress measures, lipid profiles, blood pressure, body weight or BMI were seen (juni 2004)

 

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