Acute dark chocolate and cocoa ingestion and endothelial function: a randomized controlled crossover trial. Am J Clin Nutr

Yale Prevention Research Center, Derby, CT, USA.
American Journal of Clinical Nutrition (Impact Factor: 6.77). 07/2008; 88(1):58-63.
Source: PubMed


Studies suggest cardioprotective benefits of dark chocolate containing cocoa.
This study examines the acute effects of solid dark chocolate and liquid cocoa intake on endothelial function and blood pressure in overweight adults.
Randomized, placebo-controlled, single-blind crossover trial of 45 healthy adults [mean age: 53 y; mean body mass index (in kg/m(2)): 30]. In phase 1, subjects were randomly assigned to consume a solid dark chocolate bar (containing 22 g cocoa powder) or a cocoa-free placebo bar (containing 0 g cocoa powder). In phase 2, subjects were randomly assigned to consume sugar-free cocoa (containing 22 g cocoa powder), sugared cocoa (containing 22 g cocoa powder), or a placebo (containing 0 g cocoa powder).
Solid dark chocolate and liquid cocoa ingestion improved endothelial function (measured as flow-mediated dilatation) compared with placebo (dark chocolate: 4.3 +/- 3.4% compared with -1.8 +/- 3.3%; P < 0.001; sugar-free and sugared cocoa: 5.7 +/- 2.6% and 2.0 +/- 1.8% compared with -1.5 +/- 2.8%; P < 0.001). Blood pressure decreased after the ingestion of dark chocolate and sugar-free cocoa compared with placebo (dark chocolate: systolic, -3.2 +/- 5.8 mm Hg compared with 2.7 +/- 6.6 mm Hg; P < 0.001; and diastolic, -1.4 +/- 3.9 mm Hg compared with 2.7 +/- 6.4 mm Hg; P = 0.01; sugar-free cocoa: systolic, -2.1 +/- 7.0 mm Hg compared with 3.2 +/- 5.6 mm Hg; P < 0.001; and diastolic: -1.2 +/- 8.7 mm Hg compared with 2.8 +/- 5.6 mm Hg; P = 0.014). Endothelial function improved significantly more with sugar-free than with regular cocoa (5.7 +/- 2.6% compared with 2.0 +/- 1.8%; P < 0.001).
The acute ingestion of both solid dark chocolate and liquid cocoa improved endothelial function and lowered blood pressure in overweight adults. Sugar content may attenuate these effects, and sugar-free preparations may augment them.

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    • "Clinical investigations have revealed that supplementation with flavanol-rich cocoa reliably improves a variety of cardiovascular variables, including peripheral blood pressure in pre-hypertensive and hypertensive patients (Taubert et al., 2007; Hooper et al., 2008; Ried et al., 2010), as well as in normotensive populations (Ried et al., 2012). Changes to cerebral blood flow (CBF) (Fisher et al., 2006; Sorond et al., 2008) and flow-mediated dilation (Faridi et al., 2008; Grassi et al., 2008; Monahan et al., 2011; Njike et al., 2011) have been observed following cocoa supplementation. Given the strong links between vascular health and cognitive function (Dinges, 2006), it is possible that cocoa may improve cognitive performance indirectly through improvements to CBF and vascular health. "
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    ABSTRACT: Cocoa supplementation has been associated with benefits to cardiovascular health. However, cocoa’s effects on cognition are less clear. A randomized, placebo-controlled, double-blind clinical trial (n=40, age M= 24.13 years, SD = 4.47 years) was conducted to investigate the effects of both acute (same-day) and sub-chronic (daily for four-weeks) 250mg cocoa supplementation on mood and mental fatigue, cognitive performance and cardiovascular functioning in young, healthy adults. Assessment involved repeated 10-minute cycles of the Cognitive Demand Battery (CDB) encompassing two serial subtraction tasks (Serial Threes and Sevens), a Rapid Visual Information Processing task, and a mental fatigue scale over the course of half an hour. The Swinburne University Computerised Cognitive Assessment Battery (SUCCAB) was also completed to evaluate cognition. Cardiovascular function included measuring both peripheral and central blood pressure and cerebral blood flow. At the acute time point, consumption of cocoa significantly improved self-reported mental fatigue and performance on the Serial Sevens task in cycle one of the CDB. No other significant effects were found.
    Full-text · Article · Apr 2015 · Frontiers in Pharmacology
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    • "improves coronary vasodilation, indicative of an increased bioavailability of NO (ability to improve endothelial function ), and decreases platelet reactivity (ability to decrease blood clotting) [1] [4] [6] [7]. Therefore a diet rich in flavonoids might have the potential to improve cardiovascular health [7– 9]. "
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    ABSTRACT: Introduction. The aim of this study was to assess the vascular benefits of dark chocolate in healthy and young individuals. Methods. A randomized and controlled trial was carried out involving 60 healthy volunteers, randomized into two groups: control group (CG; n = 30) and intervention group (IG; n = 30). The IG ingested a daily dosage of 10 g of dark chocolate (>75% cocoa) for a month. Blood pressure (BP), flow-mediated dilation (FMD), arterial stiffness index (ASI), aortic pulse wave velocity (PWV), and pulse wave analysis (PWA) were assessed at baseline and one week after the one-month intervention period. Results. Arterial function improved after intervention in the IG, with PWV decreasing from 6.13 ± 0.41 m/s to 5.83 ± 0.53 m/s (P = 0.02), with no significant differences observed in the CG. A significant decrease in ASI (0.16 ± 0.01 to 0.13 ± 0.01; P < 0.001) and AiX (-15.88 ± 10.75 to -22.57 ± 11.16; P = 0.07) was also depicted for the IG. Endothelial function improved in the IG, with the FMD increasing 9.31% after the 1-month intervention (P < 0.001), with no significant variation in the CG. Conclusion. The daily ingestion of 10 g dark chocolate (>75% cocoa) during a month significantly improves vascular function in young and healthy individuals.
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    • "The psychopharmacological effects of cocoa may not be limited to benzodiazepine receptor binding and resultant changes in anxiety. Cocoa polyphenols have previously been shown to reduce blood pressure (Desch et al., 2010), improve endothelial function (Faridi et al., 2008) and increase cerebral blood flow (Francis et al., 2006). Given the well-documented links between cardiovascular health and cognitive performance (Decarli, 2012), cocoa polyphenols may also have indirect effects on neuropsychological function. "
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    ABSTRACT: This study aimed to examine the acute and sub-chronic effects of cocoa polyphenols on cognition and mood. In a randomized, double-blind study, healthy middle-aged participants received a dark chocolate drink mix standardized to contain 500 mg, 250 mg or 0 mg of polyphenols (placebo) in a parallel-groups design. Participants consumed their assigned treatment once daily for 30 days. Cognition was measured with the Cognitive Drug Research system and self-rated mood with the Bond-Lader Visual Analogue Scale. Participants were tested at baseline, at 1, 2.5 and 4 h after a single acute dose and again after receiving 30 days of treatment. In total, 72 participants completed the trial. After 30 days, the high dose of treatment significantly increased self-rated calmness and contentedness relative to placebo. Mood was unchanged by treatment acutely while cognition was unaffected by treatment at all time points. This randomized controlled trial is perhaps the first to demonstrate the positive effects of cocoa polyphenols on mood in healthy participants. This provides a rationale for exploring whether cocoa polyphenols can ameliorate the symptoms associated with clinical anxiety or depression.
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