Scientific Research

Cocoa Science

Mars, Incorporated, a leader in cocoa research, has conducted numerous studies on cocoa products produced by the Cocoapro® patented process, which preserves the phytonutrient content of cocoa. Scientists have identified specific flavanols more prevalent in cocoa that are responsible for the range of health benefits.  They also know that it is not the level of cocoa or the percentage of cocoa in the product that is important with respect to circulation benefits; it's the amount of cocoa flavanols that matters. The following selection of papers illustrates the research that has gone into understanding that CocoaVia® helps maintain healthy circulation.†

 

Davison et al. Effect of cocoa flavanols and exercise on cardiometabolic risk factors in overweight and obese subjects. 2008, Int J Obesity 32(8):1289.

OBJECTIVE: Impaired endothelial function in obesity may reduce blood flow to sites of metabolism, contributing to impaired fat oxidation and insulin resistance. This study investigated the effects of cocoa flavanols and regular exercise, interventions known to improve endothelial function, on cardiometabolic function and body composition in obese individuals.

DESIGN: Overweight and obese adults were randomly assigned to high-flavanol cocoa (HF, 902 mg flavanols), HF and exercise, low-flavanol cocoa (LF, 36 mg flavanols), or LF and exercise for 12 weeks (exercise duration was 3 x 45 min per week at 75% of age-predicted maximum heart rate). Body composition was assessed by dual-energy X-ray absorptiometry at 0 and 12 weeks. Brachial artery flow-mediated dilatation (FMD), supine blood pressure (BP) and fasting plasma insulin, and glucose levels were assessed at 0, 6 and 12 weeks, respectively. Insulin sensitivity/resistance was determined using the modified homeostasis model assessment of insulin resistance (HOMA2).

RESULTS: A total of 49 subjects (M=18; F=31) completed the intervention. Baseline averages were as follows: body mass index=33.5 kg/m(2); BP=123/76 mm Hg; HOMA2=2.4; FMD=4.3%; rate of fat oxidation during exercise=0.34 g min(-1); abdominal fat=45.7% of total abdominal mass. Compared to LF, HF increased FMD acutely (2 h post-dose) by 2.4% (P<0.01) and chronically (over 12 weeks; P<0.01) by 1.6% and reduced insulin resistance by 0.31% (P<0.05), diastolic BP by 1.6 mm Hg and mean arterial BP by 1.2 mm Hg (P<0.05), independent of exercise. Regular exercise increased fat oxidation during exercise by 0.10 g min(-1) (P<0.01) and reduced abdominal fat by 0.92% (P<0.05).

CONCLUSION:
Although HF consumption was shown to improve endothelial function, it did not enhance the effects of exercise on body fat and fat metabolism in obese subjects. However, it may be useful for reducing cardiometabolic risk factors in this population.

 


 

Fisher et al. Aging and vascular response to flavanol rich cocoa. 2006, J Hypertension 24:1575.

OBJECTIVES: Strong evidence has secured aging as a powerful predictor of both cardiovascular risk and endothelial dysfunction, yet specific treatment is not available. We tested the hypothesis that vascular responsiveness to flavanol-rich cocoa increases with advancing age. We have previously shown that flavanol-rich cocoa induced peripheral vasodilation, improving endothelial function via a nitric oxide (NO)-dependent mechanism.

METHODS: We studied blood pressure and peripheral arterial responses to several days of cocoa in 15 young (< 50 years) and 19 older (> 50) healthy subjects.

RESULTS:
The nitric oxide synthase (NOS) inhibitor N(omega)-nitro-L-arginine-methyl-ester (L-NAME) induced significant pressor responses following cocoa administration only among the older
subjects: systolic blood pressure (SBP) rose 13 +/- 4 mmHg, diastolic blood pressure (DBP) 6 +/- 2 mmHg (P = 0.008 and 0.047, respectively); SBP was significantly higher in the older subjects (P < 0.05). Flow-mediated vasodilation, measured by tonometry in the finger, was enhanced with flavanol-rich cocoa in both groups, but significantly more so among the old (P = 0.01). Finally, basal pulse wave amplitude (PWA) followed a similar pattern. Four to six days of flavanol-rich cocoa caused a rise in PWA in both groups. At peak vasodilation following acute cocoa intake on the final day, both groups showed a further, significant rise in PWA. The response in the older subjects was more robust; P < 0.05. L-NAME significantly reversed dilation in both groups.

CONCLUSIONS: Flavanol-rich cocoa enhanced several measures of endothelial function to a greater degree among older than younger healthy subjects. Our data suggest that the NO-dependent vascular effects of flavanol-rich cocoa may be greater among older people, in whom endothelial function is more disturbed.

 


 

Schroeter et al.(-)Epicatechin mediates beneficial effects of flavanol-rich cocoa on vascular function in humans. 2006, PNAS 103(4):1024.

Epidemiological and medical anthropological investigations suggest that flavanol-rich foods exert cardiovascular health benefits. Endothelial dysfunction, a prognostically relevant key event in atherosclerosis, is characterized by a decreased bioactivity of nitric oxide (NO) and impaired flow-mediated vasodilation (FMD).

We show in healthy male adults that the ingestion of flavanol-rich cocoa was associated with acute elevations in levels of circulating NO species, an enhanced FMD response of conduit arteries, and an augmented microcirculation. In addition, the concentrations and the chemical profiles of circulating flavanol metabolites were determined, and multivariate regression analyses identified (-)-epicatechin and its metabolite, epicatechin-7-O-glucuronide, as independent predictors of the vascular effects after flavanol-rich cocoa ingestion.

A mixture of flavanols/metabolites, resembling the profile and concentration of circulating flavanol compounds in plasma after cocoa ingestion, induced a relaxation in preconstricted rabbit aortic rings ex vivo, thus mimicking acetylcholine-induced relaxations. Ex vivo flavanol-induced relaxation, as well as the in vivo increases in FMD, were abolished by inhibition of NO synthase. Oral administration of chemically pure (-)-epicatechin to humans closely emulated acute vascular effects of flavanol-rich cocoa.

Finally, the concept that a chronic intake of high-flavanol diets is associated with prolonged, augmented NO synthesis is supported by data that indicate a correlation between the chronic consumption of a cocoa flavanol-rich diet and the augmented urinary excretion of NO metabolites. Collectively, our data demonstrate that the human ingestion of the flavanol (-)-epicatechin is, at least in part, causally linked to the reported vascular effects observed after the consumption of flavanol-rich cocoa.

 


 

Fisher et al. Flavanol-rich cocoa induces nitric oxide-dependent vasodilation in healthy humans.  2003, J Hypertension 21:1.

BACKGROUND: Consumption of flavonoid-rich beverages, including tea and red wine, has been associated with a reduction in coronary events, but the physiological mechanism remains obscure. Cocoa can contain extraordinary concentrations of flavanols, a flavonoid subclass shown to activate nitric oxide synthase in vitro.

OBJECTIVE: To test the hypothesis that flavanol-rich cocoa induces nitric-oxide-dependent vasodilation in humans.

DESIGN: The study prospectively assessed the effects of Flavanol-rich cocoa, using both time and beverage controls. Participants were blinded to intervention; the endpoint was objective and blinded.

METHODS: Pulse wave amplitude was measured on the finger in 27 healthy people with a volume-sensitive validated calibrated plethysmograph, before and after 5 days of consumption of Flavanol-rich cocoa [821 mg of flavanols/day, quantitated as (-)-epicatechin, (+)-catechin, and related procyanidin oligomers]. The specific nitric oxide synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME) was infused intravenously on day 1, before cocoa, and on day 5, after an acute ingestion of cocoa.

RESULTS: Four days of flavanol-rich cocoa induced consistent and striking peripheral vasodilation (P = 0.009). On day 5, pulse wave amplitude exhibited a large additional acute response to cocoa (P = 0.01). L-NAME completely reversed this vasodilation (P = 0.004). In addition, intake of flavanol-rich cocoa augmented the vasodilator response to ischemia. Flavanol-poor cocoa induced much smaller responses (P = 0.005), and none was induced in the time-control study. Flavanol-rich cocoa also amplified the systemic pressor effects of L-NAME (P = 0.005).

CONCLUSION: In healthy humans, flavanol-rich cocoa induced vasodilation via activation of the nitric oxide system, providing a plausible mechanism for the protection that flavanol-rich foods induce against coronary events.