Does chocolate reduce blood pressure? A meta-analysis

From Cocoa to Chocolate: Effect of Processing on Flavanols and Methylxanthines and Their Mechanisms of Action

Despite the health benefits associated with the ingestion of the bioactive compounds in cocoa, the high concentrations of polyphenols and methylxanthines in the raw cocoa beans negatively influence the taste, confer the astringency and bitterness, and affect the stability and digestibility of the cocoa products. It is, therefore, necessary to process cocoa beans to develop the characteristic color, taste, and flavor, and reduce the astringency and bitterness, which are desirable in cocoa products. Processing, however, affects the composition and quantities of the bioactive compounds, resulting in the modification of the health-promoting properties of cocoa beans and chocolate. In this advanced review, we sought to better understand the effect of cocoa's transformational process into chocolate on polyphenols and methylxanthine and the mechanism of action of the original flavanols and methylxanthines. More data on the cocoa processing effect on cocoa bioactives are still needed for better understanding the effect of each processing step on the final polyphenolic and methylxanthine composition of chocolate and other cocoa products. Regarding the mechanisms of action, theobromine acts through the modulation of the fatty acid metabolism, mitochondrial function, and energy metabolism pathways, while flavanols mainly act though the protein kinases and antioxidant pathways. Both flavanols and theobromine seem to be involved in the nitric oxide and neurotrophin regulation.

Dose-effect relation between regular consumption of 100% cocoa powder and blood pressure in young, healthy black Africans

BACKGROUND

Some previous works have focused on dose-response relationship between cocoa consumption and blood pressure in Caucasians. As black subjects have lower nitric oxide bioavailability, the aim of this work was to determine the dose-effect relation between cocoa and blood pressure in black Africans.

METHOD

One hundred and thirty healthy black African males aged 18-30 were randomly assigned into four groups: three groups consuming 10 g, 5 g, or 2 g of cocoa powder daily for three weeks and one control group that did not consume cocoa. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were measured on day 1 (D1, before any subject consumed cocoa), D8, D15, and D22. Means of the parameters at each of the four visits and changes of the means were compared among the groups.

RESULTS

Significant decrease in SBP was noted in consumers of 10 g compared to controls in the 1st week, and compared to consumers of 2 g in the 2nd and 3rd weeks of follow-up. Means and changes of DBP were statistically similar among the four groups.

CONCLUSION

Among our cohort, decrease in SBP was significantly greater in the heavy cocoa consumer group (10 g) compared to the low consumer group (2 g), but there was no statistically significant difference when compared with the intermediate consumer group (5 g). The dose-response relationship between cocoa consumption and changes in SBP was not linear. No relationship was found between cocoa consumption and DBP.

Relationship between hemodynamic alteration and sympathetic nerve activation following a single oral dose of cinnamtannin A2

We previously found that a single dose of B-type procyanidin mixture increase in skeletal muscle blood flow (BF). We compared BF changes following administration of (-)-epicatechin (EC, monomer) and the B-type procyanidins procyanidin B2 (B2, dimer), procyanidin C1 (C1, trimer), and cinnamtannin A2 (A2, tetramer). Each chemical was administered orally to rats, followed by BF measurement in cremaster arteriole for 60 min. About 10 and 100 µg/kg of B2 and C1 elicited BF increase, the effect was potent at 100 µg/kg. BF also increased significantly after administration of 10 µg/kg A2, but not with the administration at 100 µg/kg. EC yielded no BF changes. Co-treatment with the nonselective adrenaline blocker carvedilol attenuated the BF increase seen with 10 µg/kg A2 treatment. This outcome suggested the involvement of sympathetic nerve activation in the BF increase by this dose of A2. Co-treatment of 100 µg/kg A2 with the α2 blocker yohimbine exhibited an increase of BF significantly. The α2 adrenaline receptor in the vasomotor centre is an inhibitory receptor and it regulates hemodynamics. This result suggested that high doses of A2 did not alter BF because of activating the α2 adrenergic receptor. Phosphorylation of aortic endothelial nitric oxide synthase (eNOS) increased with 10 µg/kg A2 alone or co-treatment with 100 µg/kg A2 and yohimbine, but not with co-treatment of 10 µg/kg A2 and carvedilol or 100 µg/kg A2 alone. These results imply that A2 does not directly activate eNOS, but that shear stress from the increased BF might be associated with eNOS phosphorylation.

Impact of cocoa flavanols on human health

Cocoa is a source of flavanols, and these phenolic compounds exert beneficial effects on health and aging, and reduce the risk of suffering chronic diseases (cardiovascular diseases, metabolic disorders, cancer). An increasing body of evidence has emerged to suggest that cocoa flavanols potentially are important chemopreventive natural agents. This review summarizes human studies from the past two decades, providing data related to the effects derived from cocoa intake on health and disease. Most human studies have reported beneficial effects of cocoa consumption on health and chronic diseases; however, outcomes are not unequivocal. Review of human studies enable to identify different mechanisms of action for cocoa, although they are not fully understood at present. In addition, it remains unclear whether cocoa consumption should be recommended to healthy subjects or to patients and what is the appropriate dosage or duration of cocoa consumption. Elucidation of information regarding these crucial issues could lead to cocoa use as an approach for decreasing the risk of certain chronic diseases, as well as improving health and quality of life.

Weekly Physiological Changes in Blood Pressure During Three Weeks Daily Consumption of 10 Grams of Cocoa Powder Among Young Black Africans in Côte d'Ivoire

Background

In Caucasians, regular consumption of cocoa induces a drop in arterial blood pressure via an increase in nitric oxide (NO) production. However, black individuals have a different NO biodisponibility compared to Caucasians. The aim of this study was to determine, in black Africans, the physiological variations in arterial blood pressure among cocoa consumers.

Method

In total, 49 male black African volunteers, aged between 18 and 30 years old, were randomized into two groups; those consuming 10 g of cocoa powder per day (1,680 mg of flavonoids per day) for 3 weeks (consumer group), and those not consuming cocoa (control group). Systolic (SBP) and diastolic blood pressures (DBP), and heart rate (HR) were measured in the morning on an empty stomach (fasting), on day (D) 1 (without cocoa), D8, D15, and D22. Data were collected by groups and by subgroups established according to the level of SBP, DBP, or HR on D1. The means and variations of the means (between D1 and the subsequent days) of the recorded parameters were calculated and compared between groups and between subgroups.

Results

On D8, the variations in SBP in the consumer group were significantly different from the control group (-3.72 ± 6.01 versus 0.57 ± 6.66 mmHg; p = 0.02). Between the control and consumer subgroups according to SBP, no statistical difference in the means or variations in SBP was noted. On D8 and D22, the variations in the SBP of consumers with SBP ≥ 110 mmHg on D1 were significantly different from those of other consumers (D8: -6.55 ± 5.96 versus -1.1 ± 4.93 mmHg; p = 0.01; D22: -6.63 ± 7.77 versus 0.35 ± 5.58 mmHg; p = 0.01). In the subgroups with a DBP < 75 mmHg on D1, the mean DBP of the consumers was significantly lower than that of the controls on D8 (65 ± 5 versus 69 ± 6 mmHg; p = 0.03).

Conclusion

In young black African men living in Côte d'Ivoire, regular consumption of cocoa resulted in a decrease in SBP and DBP. The decrease in SBP appeared to be greater the higher the baseline SBP was.

Chocolate consumption and risk of coronary artery disease: the Million Veteran Program

Background

Although previous studies have suggested cocoa products may promote cardiovascular health in the general population, no public data are available from patients receiving care in a national integrated health care system.

Objectives

We tested the hypothesis that regular chocolate consumption is associated with a lower risk of coronary artery disease (CAD) events among participants of the Million Veteran Program (MVP). Secondary analysis examined if the main hypothesis was observed among participants with type 2 diabetes.

Methods

We analyzed data from MVP participants who completed the food frequency section of the MVP Lifestyle Survey and were free of CAD at the time of survey completion. CAD events during follow-up (International Statistical Classification of Diseases Ninth Revision codes 410-411 and 413-414, and Tenth Revision codes I20-I25 except I25.2) were assessed using electronic health records. We fitted a Cox proportional hazard model to estimate the RR of CAD.

Results

Of 188,447 MVP enrollees with survey data, mean ± SD age was 64 ± 12.0 y and 90% were men. For regular chocolate (28.3 g/serving) consumption of <1 serving/mo, 1-3 servings/mo, 1 serving/wk, 2-4 servings/wk, and ≥5 servings/wk, crude incidence rates (per 1000 person-years) for fatal and nonfatal CAD events or coronary procedures were 20.2, 17.5, 16.7, 17.1, and 16.9, respectively, during a mean follow-up of 3.2 y. After adjusting for age, sex, race, and lifestyle factors, the corresponding HRs (95% CIs) were 1.00 (ref), 0.92 (0.87, 0.96), 0.88 (0.83, 0.93), 0.89 (0.84, 0.95), and 0.89 (0.84, 0.96), respectively (P for linear trend < 0.0001). In a secondary analysis of 47,265 diabetics, we did not observe a decreasing trend in CAD mortality among those who consumed ≥1 serving of chocolate a month compared with those who consumed <1 serving/mo.

Conclusions

Regular chocolate consumption was associated with a lower risk of CAD among veterans, but was not associated with cardiovascular disease risk in veterans with type 2 diabetes.

Effect of Cocoa and Cocoa Products on Cognitive Performance in Young Adults

Increasing evidence support a beneficial role of cocoa and cocoa products on human cognition, particularly in aging populations and patients at risk. However, thorough reviews on the efficacy of cocoa on brain processes in young adults do not exist precisely due to the limited number of studies in the matter. Thus, the aim of this study was to summarize the findings on the acute and chronic effects of cocoa administration on cognitive functions and brain health in young adults. Web of Science and PubMed databases were used to search for relevant trials. Human randomized controlled studies were selected according to PRISMA guidelines. Eleven intervention studies that involved a total of 366 participants investigating the role of cocoa on cognitive performance in children and young adults (average age ≤ 25 years old) were finally selected. Findings from individual studies confirm that acute and chronic cocoa intake have a positive effect on several cognitive outcomes. After acute consumption, these beneficial effects seem to be accompanied with an increase in cerebral blood flow or cerebral blood oxygenation. After chronic intake of cocoa flavanols in young adults, a better cognitive performance was found together with increased levels of neurotrophins. This systematic review further supports the beneficial effect of cocoa flavanols on cognitive function and neuroplasticity and indicates that such benefits are possible in early adulthood.

Using digital health technology to evaluate the impact of chocolate on blood pressure: Results from the COCOA-BP study

Background

High blood pressure (BP) is a major risk factor for cardiovascular disease (CVD). Consumption of dark chocolate, which is high in flavonoids that may reduce CVD risk, is an attractive intervention to reduce to BP. Additionally, the use of mobile health (mHealth) technologies (eg, telehealth, smartphones, and wearable devices) can improve outcomes in patients with CVD.

Objective

The purpose of this study was to investigate the impact of dark chocolate intake on BP, subject use of mHealth, and integration of mHealth into a clinical trial.

Methods

The COCOA-BP (ChOcolate COnsumption And Blood Pressure) study was a prospective, single-center, pre-/postintervention study that enrolled 62 healthy volunteers. The study consisted of 3 phases: smartwatch/smart BP monitor familiarization and washout from chocolate (week 1); control (week 2); and intervention (weeks 3 and 4). During the intervention phase, subjects consumed 50 g of dark chocolate per day. The primary endpoint was change in resting systolic BP between the intervention and control phases. Additional endpoints included device accuracy and correlation with physical activity.

Results

Mean resting systolic BP was 116.4 mm Hg before chocolate intake among 62 participants (mean age 37 years; 61% female). After chocolate intake, mean resting systolic BP was 116.0 mm Hg (difference –0.4; P = .69). These findings suggest that 2 weeks of dark chocolate intake did not reduce resting systolic BP. There was poor agreement between mHealth device and standard (nurse-performed) measurements.

Conclusion

In this study, short-term dark chocolate intake did not seem to reduce BP. mHealth technology shows great potential for use in clinical studies, but challenges related to device accuracy and compliance need to be addressed.

The influence of different concentrations of flavanol chocolate bars under acute supplement conditions on exercise and performance

OBJECTIVE

The purpose of this study was to assess the effects and acute dosage of different flavanol concentrations in a dark chocolate bar on physiological parameters during steady state (SS) and incremental exercise.

METHODS

In a double-blind, randomised, crossover study, 15 healthy participants with a mean ± SD age of 30 ± 7 years; stature 176.8 ± 8.6 cm and body mass 80.3 ± 8.4 kg supplemented with high flavanol (HF) (1060 mg), moderate flavanol (MF) (746 mg), low flavanol (LF) (406 mg), or a control (CON) (88 mg) chocolate bar (~ 34 g), 2 h prior to 40 min of SS cycling (80% gas-exchange threshold) followed by an incremental test to volitional fatigue. During the SS cycle oxygen consumption ([Formula: see text]), respiratory exchange ratio (RER) and heart rate (HR) were continuously monitored. Plasma samples were collected prior to commencing exercise to determine nitrate (NO₃^-) and nitrite (NO₂^-) levels under each condition.

RESULTS

There was no observed effect between flavanol concentrations on [Formula: see text], RER, and HR during SS cycling (P > 0.05). [Formula: see text], peak power, HR peak, and RER peak also did not significantly differ between conditions (P > 0.05). There was a small trend for higher plasma NO₂^- levels following higher flavanol concentration; however, this did not reach statistical significance (P > 0.05).

CONCLUSION

Acute supplementation with cocoa of differing flavanol concentrations does not appear to have any effect on exercise and performance. It is plausible that longer flavanol supplementation periods might have greater accumulative effects and thus may potentially elicit a larger effect.

Flavonoids and Reduction of Cardiovascular Disease (CVD) in Chronic Obstructive Pulmonary Disease (COPD)

BACKGROUND

Chronic Obstructive Pulmonary Disease (COPD) and Cardiovascular Diseases (CV) Often Coexist. COPD and CVD are complex diseases characterized by a strict interaction between environment and genetic. The mechanisms linking these two diseases are complex, multifactorial and not entirely understood, influencing the therapeutic approach. COPD is characterized by several comorbidities, it hypothesized the treatment of cardiovascular co-morbidities that may reduce morbidity and mortality. Flavonoids are an important class of plant low molecular weight Secondary Metabolites (SMs). Convincing data from laboratory, epidemiological, and human clinical studies point the important effects on CVD risk prevention.

OBJECTIVE

This review aims to provide up-to-date information on the ability of Flavonoids to reduce the CVD risk.

CONCLUSION

Current studies support the potential of Flavonoids to prevent the risk of CVD. Well-designed clinical studies are suggested to evaluate advantages and limits of Flavonoids for managing CVD comorbidity in COPD.

The effect of cocoa consumption on markers of oxidative stress: A systematic review and meta-analysis of interventional studies

A number of studies have examined the beneficial effects of cocoa consumption on markers of oxidative stress in different population, however, the findings have been inconclusive. Herein, we systematically reviewed available interventional studies to elucidate the overall impact of cocoa consumption on markers of oxidative stress among adult population. PubMed, Cochrane's library, Science Direct, Scopus, Google scholar and ISI web of science databases were searched for all available literature until March 2019 for relevant studies. The Jadad scale was used to assess the quality of each study. A total of 48 studies out of 1402 met the inclusion criteria and were included in our systematic review and 16 of them were entered in meta-analysis. The pooled estimate from the random-effect model showed cocoa consumption significantly reduced malondialdehyde (SMD: -0.71; 95 % CI, -1.41 to -0.01; P = 0.048) and 8-iso-prostaglandin F2α (WMD: -43.76; 95 % CI, -76.25 to -11.28; P = 0.008) but not the other markers of oxidative stress. Our findings support the concept that cocoa consumption plays an important role in the human metabolic pathway through reducing the oxidative stress. In order to draw a firm link between cocoa and oxidative stress, more clinical trials with adequate sample size and sufficient follow-up periods are warranted.

The role of nutraceuticals in prevention and treatment of hypertension: An updated review of the literature

Hypertension (HTN) is a worldwide epidemic in both developed and developing countries. It is one of the leading causes of major health problems such as cardiovascular disease, stroke, and heart attack. In recent years, several studies have reported associations between specific dietary ingredients and improving HTN. Nutraceuticals are natural food components with pharmacological properties. Reports suggest that functional foods and nutraceutical ingredients might support patients to obtain the desired therapeutic blood pressure (BP) goals and reduce cardiovascular risks by modulating various risk factors such as oxidative stress, renin-angiotensin system hyperactivity, inflammation, hyperlipidemia, and vascular resistance. We review the recent clinical experiments that have evaluated the biological and pharmacological activities of several types of nutraceuticals, including sour tea, cocoa, common spices, vitamin C, vitamin E, lycopene, flavonoids, coenzyme Q10, milk's tripeptides, calcium, magnesium, polyunsaturated fatty acids, and prebiotics in preventing and treating HTN. This review summarizes recent knowledge about the impact of common nutraceuticals for the regulation of BP.

The Effect of a Single Dose of Dark Chocolate on Cardiovascular Parameters and Their Reactivity to Mental Stress

Objective: This study investigated the effect of a single administration of dark or milk chocolate on blood pressure (BP), heart rate (HR), and double product (DP) in young healthy women at rest and during acute mental stress.Method: Measurements consisted of anthropometry, BP, and HR. Mean arterial BP (MAP) and DP were computed. The relative reactivity of individual variables was quantified as to their percentage change during the rest or test of mental arithmetic (MA) with respect to the respective baseline value. All subjects underwent two tests of MA-one before chocolate administration and the second one 2 hours after chocolate (1 mg/g of body weight) ingestion.Results: Two hours after ingestion at rest, dark chocolate administration resulted in a significant increase in relative values of systolic BP and DP by 5.1% ± 1.4% and 13.7% ± 3.2%, respectively, compared to the responses in the milk chocolate group (-2.4% ± 1.6% and 0.6% ± 3.4%, respectively, p < 0.04 for both comparisons) without changes in diastolic BP, HR, and MAP. During MA-induced acute stress, the relative magnitude of the reactivity of diastolic BP, HR, MAP, and DP decreased by about 10, 16, 8, and 23 percentage points, respectively, 2 hours after ingestion of dark chocolate compared to the relative reactivity determined before dark chocolate ingestion. Milk chocolate failed to affect any of the above-mentioned parameters at rest or during stress.Conclusions: The single oral intake of 85% dark chocolate increased relative values of systolic BP and DP at rest but buffered the reactivity of diastolic BP, HR, MAP, and DP during mental stress, which was not found after ingestion of milk chocolate. Thus, dark chocolate might have a beneficial effect during acute stress due to its ability to buffer cardiovascular reactivity in young healthy women.

The effects of polyphenols and other bioactives on human health

Although deficiencies in polyphenol intake do not result in specific deficiency diseases, adequate intake of polyphenols could confer health benefits, especially with regard to chronic diseases. Tea, cocoa, fruits, and berries, as well as vegetables, are rich in polyphenols. Flavan-3-ols from cocoa have been found to be associated with a reduced risk of stroke, myocardial infarction, and diabetes, as well as improvements in lipids, endothelial-dependent blood flow and blood pressure, insulin resistance, and systemic inflammation. The flavonoid quercetin and the stilbene resveratrol have also been associated with cardiometabolic health. Although polyphenols have been associated with improved cerebral blood flow, evidence of an impact on cognition is more limited. The ability of dietary polyphenols to produce clinical effects may be due, at least in part, to a bi-directional relationship with the gut microbiota. Polyphenols can impact the composition of the gut microbiota (which are independently associated with health benefits), and gut bacteria metabolize polyphenols into bioactive compounds that produce clinical benefits. Another critical interaction is that of polyphenols with other phytochemicals, which could be relevant to interpreting the health parameter effects of polyphenols assayed as purified extracts, whole foods, or whole food extracts.

Effects of Extra Virgin Olive Oil and Apples Enriched-Dark Chocolate on Endothelial Progenitor Cells in Patients with Cardiovascular Risk Factors: A Randomized Cross-Over Trial

Background: Endothelial dysfunction has been associated to cardiovascular outcomes in patients with cardiovascular risk factors. Circulating endothelial progenitor cells (EPCs) play an important physiological role for their reparative potential of vascular integrity, but are numerically reduced and functionally impaired in patients with cardiovascular risks. This study assesses the effects of Extra Virgin Olive Oil (EVOO) and apple-enriched dark chocolate intake on the blood levels of EPCs. Methods: Thirty volunteers with cardiovascular risk factors, enrolled in a randomised, crossover, four-weeks trial, received a solid dark chocolate bar (40 g/day) containing 10% EVOO or 2.5% dry apples. Urine samples were analyzed for endogenous metabolites. Circulating EPCs levels, clinical data and anthropometric examinations were collected. Results: 26 volunteers (M/F:14/12, 51 ± 9 years of age) completed the study. Comparison of pre-post intervention revealed a significant increase in EPCs levels associated with EVOO-dark chocolate consumption. Most biochemical parameters were not significantly modified by both chocolates. Conclusions: This study shows that a daily consumption of a non fattening dose of dark chocolate enriched with EVOO improves blood levels of EPCs, a well known surrogate biologic marker for endothelial function.

Cardioprotective Mechanisms of Cocoa

Cardiovascular diseases are the main cause of deaths in highly developed countries. Dietetic interventions that involve recommendations for consumption of products with a confirmed health-improving action are an important aspect of prevention of cardiovascular diseases. Cocoa is an alimentary product with significant cardioprotective potential due to its high content of bioactive compounds. The aim of the present study was to review the most recent literature concerning the effectiveness and mechanisms of action of compounds contained in cocoa with regard to selected cardiovascular risk factors and cardiometabolic markers. Study results indicate that cocoa consumption, especially in the form of dark chocolate with high flavonoid content, may be a good strategy to diminish cardiovascular risk due to its beneficial effect on platelet aggregation, decreasing blood pressure, diminishing dyslipidemia, and decreasing blood plasma glucose concentration. Many studies have shown that cocoa-derived flavonoids have antioxidant and anti-inflammatory activity and also play a significant role in preventing insulin resistance. However, in order to completely confirm the potential cardiovascular benefits, it is necessary to conduct larger and longer studies, also with regard to potential dangers associated with long-term consumption of large amounts of flavonoids and determination of a safe and effective dose. Key teaching points Cocoa consumption may be a good strategy in diminishing cardiovascular risk. Beneficial effects on platelet aggregation, blood pressure, dyslipidemia, glycemia, as well as antioxidant and anti-inflammatory activity are observed. There is a need to conduct larger and longer studies to determine a safe and effective dose of cocoa flavonoids.

Single oral administration of flavan 3-ols induces stress responses monitored with stress hormone elevations in the plasma and paraventricular nucleus

We previously confirmed that postprandial alterations in the circulation and metabolism after a single oral dose of flavan 3-ols (mixture of catechin and catechin oligomers) were involved in an increase in sympathetic nervous activity. However, it is well known that, in response to various stresses, activation of the hypothalamic-pituitary-adrenal (HPA) axis occurs together with sympathetic nerve activity, which is associated with activation of the sympathetic-adrenal-medullary (SAM) axis. In this study, we examined whether the HPA axis was activated after a single dose of flavan 3-ols. We administered an oral dose of 10 or 50 mg/kg flavan 3-ols to male ICR mice, removed the brains, and fixed them in paraformaldehyde-phosphate buffer. Other animals that were treated similarly were decapitated, and blood was collected. In the paraventricular nucleus (PVN), c-fos mRNA expression increased significantly at 15 min after administration of either 10 or 50 mg/kg flavan 3-ols. Corticotropin-releasing hormone (CRH) mRNA expression levels significantly increased at 240 min after administration of 10 mg/kg flavan 3-ols, and at 60 min after administration of 50 mg/kg flavan 3-ols. Plasma corticosterone levels were also significantly increased at 240 min after ingestion of 50 mg/kg flavan 3-ols. In this experiment, we confirmed that the ingestion of flavan 3-ols acted as a stressor in mammals with activation both the SAM and HPA axes.

Effects of cocoa-enriched diet on orofacial pain in a murine model

OBJECTIVES

To investigate and discuss the effects of cocoa on orofacial pain.

SETTING AND SAMPLE POPULATION

The Department of Orthodontics at the University of Florida (UF). Male and female hairless rats (N=20/group) were tested.

MATERIALS AND METHODS

Rats were tested using the Orofacial Pain Assessment Device (OPAD) before and after changing their food from the standard chow to a cocoa-enriched or control-equivalent diet.

RESULTS

Male rats fed the cocoa diet had a significantly higher operant pain index when tested at 37°C as compared to control diet-fed animals. Female rats on the cocoa diet had a significantly higher pain index when tested at 18°C and 44°C, as compared to animals fed the control diet. Capsaicin-induced pain was inhibited, with cocoa-diet male rats having a significantly higher pain index than control-diet male rats and cocoa-diet female rats at both 37°C and 44°C. Cocoa-diet female rats had a significantly higher pain index at 44°C than control-diet females. Mechanical sensitivity was affected following capsaicin cream, with a significantly decreased tolerated bottle distance in both cocoa- and control-diet animals, but there was no difference between cocoa- and control-diet groups.

CONCLUSION

Using the OPAD operant system, we demonstrated that a diet rich in cocoa was effective in inhibiting neurogenic inflammatory pain in rats. This has implications for the use of novel alternative therapies such as diet modification for pain control.

A nutritive dose of pure (-)-epicatechin does not beneficially affect increased cardiometabolic risk factors in overweight-to-obese adults-a randomized, placebo-controlled, double-blind crossover study

Background

Regular cocoa consumption has been shown to reduce blood pressure, improve lipid profiles, and increase insulin sensitivity and flow-mediated dilatation in healthy adults. It is assumed that these effects can be attributed to polyphenolic cocoa ingredients such as flavanols, especially to (-)-epicatechin. Nutritive intervention studies to prove this hypothesis are scarce.

Objective

We aimed to evaluate whether regular consumption of 25 mg of pure (-)-epicatechin can affect increased cardiometabolic risk factors [blood pressure, glucose and lipid metabolism, low-density lipoprotein (LDL) oxidation] in overweight-to-obese subjects.

Design

Forty-eight overweight or obese nonsmokers [body mass index (kg/m2) ≥25.0, ages 20-65 y] with clear signs of metabolic syndrome (blood pressure ≥130/85 mm Hg, glucose >5.55 mmol/L, or triglycerides >1.69 mmol/L or cholesterol >5.2 mmol/L in fasting blood) and without chronic diseases were included in a randomized, placebo-controlled, double-blind crossover study. Participants ingested daily 25 mg (-)-epicatechin (encapsulated) or placebo for 2-wk in random order (2-wk washout). After an overnight fast, blood pressure was monitored and blood samples were collected before and after both treatments. Anthropometric data were determined at each visit. Dietary intake was assessed by 3-d food records during both treatments and during run-in and washout phase.

Results

Supplementation of pure (-)-epicatechin did not significantly affect blood pressure, glucose, insulin, homeostasis model assessment of insulin resistance, triglycerides, or total, LDL, or HDL cholesterol. Oxidized LDL, vitamins C and E, and β-carotene in plasma were not modulated. Body weight, fat mass, fat distribution, and the intake of energy, nutrients, and (-)-epicatechin from food remained stable throughout the study.

Conclusions

Daily intake of 25 mg of pure (-)-epicatechin for 2 wk does not reduce cardiometabolic risk factors in overweight-to-obese adults. Thus, the hypothesis that the cardioprotective effects of regular cocoa consumption are exclusively ascribed to (-)-epicatechin should be reconsidered. The study was registered at the German Clinical Trial Register as DRKS-ID: DRKS00009846.

Cardioprotection by Cocoa Polyphenols and ω-3 Fatty Acids: A Disease-Prevention Perspective on Aging-Associated Cardiovascular Risk

Cardiovascular disease (CVD) remains the leading cause of death today. Many of the biochemical alterations associated with the pathophysiology of CVD can be modified by adequate intakes of bioactive nutrients through a correct diet or supplementation. Recently, there has been growing public and clinical interest in cocoa polyphenols (CPs) and omega-3 (ω-3) fatty acids. A plethora of nutritional intervention trials and experimental studies demonstrates that consumption of these bioactive food compounds is beneficial to promote cardiovascular health. The purpose of this review is to summarize the major cardioprotective effects of CPs and ω-3 fatty acids, providing a scientific rationale for incorporating the combination of these molecules as a nutritional intervention in the prevention of CVD. Although several studies have shown the individual cardioprotective nature of these compounds, a combination treatment with CPs and ω-3 fatty acids may be a promising approach to enhance the preventive value of these molecules and reduce cardiovascular risk factors associated with aging. Therefore, this article also reviews some of the key studies on the interaction between CPs and the metabolism of ω-3 fatty acids.

Theobromine consumption does not improve fasting and postprandial vascular function in overweight and obese subjects

Backgound

Theobromine, a component of cocoa, may favorably affect conventional lipid-related cardiovascular risk markers, but effects on flow-mediated dilation (FMD) and other vascular function markers are not known.

Objective

To evaluate the effects of 4-week theobromine consumption (500 mg/day) on fasting and postprandial vascular function markers.

Design

In a randomized, double-blind crossover study, 44 apparently healthy overweight (N = 30) and obese (N = 14) men and women with low HDL-C concentrations, consumed daily 500 mg theobromine or placebo for 4 weeks. After 4 weeks, FMD, peripheral arterial tonometry (PAT), augmentation index (AIx), pulse wave velocity (PWV), blood pressure (BP) and retinal microvasculature measurements were performed. These measurements were carried out under fasting conditions and 2.5 h after a high-fat mixed meal challenge.

Results

4-week theobromine consumption did not change fasting vascular function markers, except for a decrease in central AIx (cAIx, − 1.7 pp, P = 0.037) and a trend towards smaller venular calibers (− 2 µm, P = 0.074). Consuming a high-fat mixed meal decreased FMD (0.89 pp, P = 0.002), reactive hyperemia index (RHI, − 0.30, P < 0.001), peripheral systolic BP (SBP, − 3 mmHg, P ≤ 0.001), peripheral diastolic BP (DBP, − 2 mmHg, P ≤ 0.001), central SBP (− 6 mmHg, P ≤ 0.001) and central DBP (− 2 mmHg, P ≤ 0.001), but increased heart rate (HR, 2 bpm, P < 0.001). Theobromine did not modify these postprandial effects, but increased postprandially the brachial artery diameter (0.03 cm, P = 0.015), and decreased the cAIx corrected for a HR of 75 (cAIx75, − 5.0 pp, P = 0.004) and peripheral AIx (pAIx, − 6.3 pp, P = 0.017).

Conclusion

Theobromine consumption did not improve fasting and postprandial endothelial function, but increased postprandial peripheral arterial diameters and decreased the AIx. These findings do not suggest that theobromine alone contributes to the proposed cardioprotective effects of cocoa.

This trial was registered on clinicaltrials.gov under study number NCT02209025.

Electronic supplementary material

The online version of this article (10.1007/s00394-018-1612-6) contains supplementary material, which is available to authorized users.

Sensory profiling and consumer acceptability of new dark cocoa bars containing Tuscan autochthonous food products

A new set of cocoa bars named Toscolata^® were developed containing top‐quality extra virgin olive oil, dried apples cultivars, and chestnut flour. The present work has been conducted to define the sensory profile of these products through tasting by trained experts and consumers to study the acceptability, preference, and quality perception. The four sensorial profiles of the bars differed in the level of persistence, bitterness, aromaticity, acidity, astringency, and tastiness. In particular, the sour attribute could be traced to the presence of dried apple. Bars containing apple and chestnut flour obtained higher acceptance ratings, compared to those with extra virgin olive oil. The bar with chestnut flour was preferred by consumers who considered it to be sweeter due to the presence of natural sugars, which lowered the bitter sensation of cocoa. These results showed that the selection of the preferred bar by consumers was mainly based on the level of bitterness and, in particular, elderly consumers expressed a strong preference for the sweetest product. As far as we know, this is the first study comparing the results of a panel of expert tasters with that of consumers in the tasting of dark chocolate.

Role of Dietary Antioxidants in the Preservation of Vascular Function and the Modulation of Health and Disease

In vascular diseases, including hypertension and atherosclerosis, vascular endothelial dysfunction (VED) occurs secondary to altered function of endothelial nitric oxide synthase (eNOS). A novel redox regulated pathway was identified through which eNOS is uncoupled due to S-glutathionylation of critical cysteine residues, resulting in superoxide free radical formation instead of the vasodilator molecule, nitric oxide. In addition, the redox sensitive cofactor tetrahydrobiopterin, BH₄, is also essential for eNOS coupling. Antioxidants, either individually or combined, can modulate eNOS uncoupling by scavenging free radicals or impairing specific radical generating pathways, thus preventing oxidative stress and ameliorating VED. Epidemiological evidence and dietary guidelines suggest that diets high in antioxidants, or antioxidant supplementation, could preserve vascular health and prevent cardiovascular diseases (CVDs). Therefore, the purpose of this review is to highlight the possible role of dietary antioxidants in regulating eNOS function and uncoupling which is critical for maintenance of vascular health with normal blood flow/circulation and prevention of VED. We hypothesize that a conditioned dietary approach with suitable antioxidants may limit systemic oxidation, maintain a beneficial ratio of reduced to oxidized glutathione, and other redox markers, and minimize eNOS uncoupling serving to prevent CVD and possibly other chronic diseases.

Nutritional Supplements for the Treatment of Hypertension: A Practical Guide for Clinicians

Nutraceuticals are dietary components with pharmacologic properties that can be used to treat various disease states. There is growing interest among patients in the use of nutraceuticals for the management of hypertension; as such, it is important that clinicians are prepared to engage in meaningful discussions with their patients about these substances. Flavonoids, beetroot, garlic, and unsaturated fats have garnered significant attention for their blood pressure lowering properties. We review the clinical evidence and reported mechanisms of action for these substances in an attempt to offer a practical guide for clinicians to engage with patients who are highly motivated to seek out nutraceutical therapies to manage their hypertension.

Cocoa, Blood Pressure, and Vascular Function

Cardiovascular disease (CVD) represents the most common cause of death worldwide. The consumption of natural polyphenol-rich foods, and cocoa in particular, has been related to a reduced risk of CVD, including coronary heart disease and stroke. Intervention studies strongly suggest that cocoa exerts a beneficial impact on cardiovascular health, through the reduction of blood pressure (BP), improvement of vascular function, modulation of lipid and glucose metabolism, and reduction of platelet aggregation. These potentially beneficial effects have been shown in healthy subjects as well as in patients with risk factors (arterial hypertension, diabetes, and smoking) or established CVD (coronary heart disease or heart failure). Several potential mechanisms are supposed to be responsible for the positive effect of cocoa; among them activation of nitric oxide (NO) synthase, increased bioavailability of NO as well as antioxidant, and anti-inflammatory properties. It is the aim of this review to summarize the findings of cocoa and chocolate on BP and vascular function.

Can flavonoid-rich chocolate modulate arterial elasticity and pathological uterine artery Doppler blood flow in pregnant women? A pilot study

INTRODUCTION

Dark chocolate has shown beneficial effects on cardiovascular health and might also modulate hypertensive complications in pregnancy and uteroplacental blood flow. Increased uteroplacental resistance is associated with systemic arterial stiffness. We aimed to investigate the short-term effect of flavonoid-rich chocolate on arterial stiffness and Doppler blood flow velocimetry indexes in pregnant women with compromised uteroplacental blood flow.

METHODS

Doppler blood flow velocimetry and digital pulse wave analysis (DPA) were performed in 25 women pregnant in the second and third trimesters with uterine artery (UtA) score (UAS) 3-4, before and after 3 days of ingestion of chocolate with high flavonoid and antioxidant contents. UtA pulsatility index (PI), UtA diastolic notching, UAS (semiquantitative measure of PI and notching combined), and umbilical artery PI were calculated, and DPA variables representing central and peripheral maternal arteries were recorded.

RESULTS

Mean UtA PI (p = .049) and UAS (p = .025) significantly decreased after chocolate consumption. There were no significant changes in UtA diastolic notching or any DPA indexes of arterial stiffness/vascular tone.

CONCLUSION

Chocolate may have beneficial effects on the uteroplacental circulation, but in this pilot study, we could not demonstrate effects on arterial vascular tone as assessed by DPA.

Effect of cocoa on blood pressure

BACKGROUND

High blood pressure is an important risk factor for cardiovascular disease, contributing to about 50% of cardiovascular events worldwide and 37% of cardiovascular-related deaths in Western populations. Epidemiological studies suggest that cocoa-rich products reduce the risk of cardiovascular disease. Flavanols found in cocoa have been shown to increase the formation of endothelial nitric oxide which promotes vasodilation and therefore blood pressure reduction. Here we update previous meta-analyses on the effect of cocoa on blood pressure.

OBJECTIVES

To assess the effects on blood pressure of chocolate or cocoa products versus low-flavanol products or placebo in adults with or without hypertension when consumed for two weeks or longer.

SEARCH METHODS

This is an updated version of the review initially published in 2012. In this updated version, we searched the following electronic databases from inception to November 2016: Cochrane Hypertension Group Specialised Register, CENTRAL, MEDLINE and Embase. We also searched international trial registries, and the reference lists of review articles and included trials.

SELECTION CRITERIA

Randomised controlled trials (RCTs) investigating the effects of chocolate or cocoa products on systolic and diastolic blood pressure in adults for a minimum of two weeks duration.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the risks of bias in each trial. We conducted random-effects meta-analyses on the included studies using Review Manager 5. We explored heterogeneity with subgroup analyses by baseline blood pressure, flavanol content of control group, blinding, age and duration. Sensitivity analyses explored the influence of unusual study design.

MAIN RESULTS

Thirty-five trials (including 40 treatment comparisons) met the inclusion criteria. Of these, we added 17 trials (20 treatment comparisons) to the 18 trials (20 treatment comparisons) in the previous version of this updated review.Trials provided participants with 30 to 1218 mg of flavanols (mean = 670 mg) in 1.4 to 105 grams of cocoa products per day in the active intervention group. The control group received either a flavanol-free product (n = 26 treatment comparisons) or a low-flavanol-containing cocoa powder (range 6.4 to 88 mg flavanols (mean = 55 mg, 13 treatment comparisons; 259 mg, 1 trial).Meta-analyses of the 40 treatment comparisons involving 1804 mainly healthy participants revealed a small but statistically significant blood pressure-reducing effect of flavanol-rich cocoa products compared with control in trials of two to 18 weeks duration (mean nine weeks):Mean difference systolic blood pressure (SBP) (95% confidence interval (CI): -1.76 (-3.09 to -0.43) mmHg, P = 0.009, n = 40 treatment comparisons, 1804 participants;Mean difference diastolic blood pressure (DBP) (95% CI): -1.76 (-2.57 to -0.94) mmHg, P < 0.001, n = 39 treatment comparisons, 1772 participants.Baseline blood pressure may play a role in the effect of cocoa on blood pressure. While systolic blood pressure was reduced significantly by 4 mmHg in hypertensive people (n = 9 treatment comparisons, 401 participants), and tended to be lowered in prehypertensive people (n= 8 treatment comparisons, 340 participants), there was no significant difference in normotensive people (n = 23 treatment comparisons, 1063 participants); however, the test for subgroup differences was of borderline significance (P = 0.08; I² = 60%), requiring further research to confirm the findings.Subgroup meta-analysis by blinding suggested a trend towards greater blood pressure reduction in unblinded trials compared to double-blinded trials, albeit statistically not significant. Further research is needed to confirm whether participant expectation may influence blood pressure results. Subgroup analysis by type of control (flavanol-free versus low-flavanol control) did not reveal a significant difference.Whether the age of participants plays a role in the effect of cocoa on blood pressure, with younger participants responding with greater blood pressure reduction, needs to be further investigated.Sensitivity analysis excluding trials with authors employed by trials sponsoring industry (33 trials, 1482 participants) revealed a small reduction in effect size, indicating some reporting bias.Due to the remaining heterogeneity, which we could not explain in terms of blinding, flavanol content of the control groups, age of participants, or study duration, we downgraded the quality of the evidence from high to moderate.Results of subgroup analyses should be interpreted with caution and need to be confirmed or refuted in trials using direct randomised comparisons.Generally, cocoa products were highly tolerable, with adverse effects including gastrointestinal complaints and nausea being reported by 1% of participants in the active cocoa intervention group and 0.4% of participants in the control groups (moderate-quality evidence).

AUTHORS' CONCLUSIONS

This review provides moderate-quality evidence that flavanol-rich chocolate and cocoa products cause a small (2 mmHg) blood pressure-lowering effect in mainly healthy adults in the short term.These findings are limited by the heterogeneity between trials, which could not be explained by prespecified subgroup analyses, including blinding, flavanol content of the control groups, age of participants, or study duration. However, baseline blood pressure may play a role in the effect of cocoa on blood pressure; subgroup analysis of trials with (pre)hypertensive participants revealed a greater blood pressure-reducing effect of cocoa compared to normotensive participants with borderline significance.Long-term trials investigating the effect of cocoa on clinical outcomes are also needed to assess whether cocoa has an effect on cardiovascular events and to assess potential adverse effects associated with chronic ingestion of cocoa products.

Catechins as Potential Mediators of Cardiovascular Health

The impact of diet on cardiovascular disease has become an increasingly relevant topic as ongoing epidemiological evidence continues to demonstrate clear associations with disease burden and mortality. Certain diets, such as those high in sodium and saturated fat, are associated with cardiovascular disease states, while other diets can be cardioprotective. However, there is limited knowledge on how the micro- and macronutrients within such cardioprotective diets afford their benefits. One such micronutrient is the catechin class, which are naturally occurring compounds in plant foods, such as teas, cocoa, wine, pears, and apples. Recent evidence reveals that catechins may be a key mediator in cardiovascular health via mechanisms of blood pressure reduction, flow-mediated vasodilation, and atherosclerosis attenuation. This review evaluates the current literature on the interplay between catechins and cardiovascular disease, which may have important implications for nutrition counseling and pharmaceutical drug development.

A single dose of dark chocolate increases parasympathetic modulation and heart rate variability in healthy subjects

ABSTRACT Objective: The aim of this study was to investigate the acute effect of a single dose of dark chocolate (70% cocoa) on blood pressure and heart rate variability. Methods: Thirty-one healthy subjects (aged 18-25 years; both sexes) were divided into two groups: 10 subjects in the white chocolate (7.4 g) group and 21 in the dark chocolate (10 g) group; measurements were performed at the university's physiology lab. An electrocardiogram measured the sympathovagal balance by spectral and symbolic analysis. Results: A single dose of dark chocolate significantly reduced systolic blood pressure and heart rate. After consuming 10 g of dark chocolate, significant increases were observed for heart rate variability, standard deviation of RR intervals standard deviation of all NN intervals, square root of the mean squared differences between adjacent normal RR intervals root mean square of successive differences, and an increase in the high frequency component in absolute values, representing the parasympathetic modulation. Conclusion: In conclusion the importance of our results lies in the magnitude of the response provoked by a single dose of cocoa. Just 10 g of cocoa triggered a significant increase in parasympathetic modulation and heart rate variability. These combined effects can potentially increase life expectancy because a reduction in heart rate variability is associated with several cardiovascular diseases and higher mortality.

(-)-Epicatechin Prevents Blood Pressure Increase and Reduces Locomotor Hyperactivity in Young Spontaneously Hypertensive Rats

This study investigated the effects of subchronic (−)-epicatechin (Epi) treatment on locomotor activity and hypertension development in young spontaneously hypertensive rats (SHR). Epi was administered in drinking water (100 mg/kg/day) for 2 weeks. Epi significantly prevented the development of hypertension (138 ± 2 versus 169 ± 5 mmHg, p < 0.001) and reduced total distance traveled in the open-field test (22 ± 2 versus 35 ± 4 m, p < 0.01). In blood, Epi significantly enhanced erythrocyte deformability, increased total antioxidant capacity, and decreased nitrotyrosine concentration. In the aorta, Epi significantly increased nitric oxide (NO) synthase (NOS) activity and elevated the NO-dependent vasorelaxation. In the left heart ventricle, Epi increased NOS activity without altering gene expressions of nNOS, iNOS, and eNOS. Moreover, Epi reduced superoxide production in the left heart ventricle and the aorta. In the brain, Epi increased nNOS gene expression (in the brainstem and cerebellum) and eNOS expression (in the cerebellum) but had no effect on overall NOS activity. In conclusion, Epi prevented the development of hypertension and reduced locomotor hyperactivity in young SHR. These effects resulted from improved cardiovascular NO bioavailability concurrently with increased erythrocyte deformability, without changes in NO production in the brain.

Onset of a hypotensive effect following ingestion of flavan 3-ols involved in the activation of adrenergic receptors

A lot of epidemiological and intervention studies support the hypotensive action resulting from ingestion of foods rich in flavan 3-ols. However, the mechanisms of this action remain unclear. We have reported previously on the alteration of the micro- and systemic circulations after administration of a flavan 3-ol fraction (FL) derived from cocoa in mammals. We also confirmed that blood catecholamine levels increase significantly after administration of FL. In the present study, we examined whether adrenaline receptors are involved in the hemodynamic changes using several adrenaline receptor (AR) blockers. First, we confirmed that mean blood pressure (MBP) decreased significantly and aortic endothelial nitric oxide synthase (eNOS) levels increased significantly following oral treatment of 10mg/kg FL for 2 weeks in normal rats compared with vehicle administration. However, these changes were not observed with treatment of 1mg/kg (-)-epicatechin (EC), which contains nearly equivalent amount of 10mg/kg FL. Secondly, we observed that a single dose of FL produced different hemodynamic changes, such as a transient elevation in heart rate (HR) after ingestion of 1-100mg/kg FL, but not with 1mg/kg EC. Furthermore, although MBP rose transiently after 1 and 10mg/kg FL, this effect was not observed with 100mg/kg or 1mg/kg EC. The increases in HR, MBP, and aortic phosphorylated eNOS (p-eNOS) induced by 10mg/kg FL were prevented completely by pretreatment with the AR blocker, carvedilol. Combination treatment with 100mg/kg FL and an α1AR blocker, prazosin, significantly reduced MBP, whereas the elevation in HR was enhanced. In addition, after pretreatment with the β2AR blocker, butoxamine, we observed no significant hemodynamic changes with or without 100mg/kg FL. Moreover, the combination of 100mg/kg FL and the α2AR blocker, yohimbine, markedly increased MBP, HR and aortic p-eNOS level. These results suggested that the postprandial hemodynamic changes after a single oral dose of FL were induced by an adrenergic effect. This adrenomimetic activity suggested the involvement of a hypotensive effect of FL.

Update in Hypertension Therapy

Hypertension is the leading cause of early mortality in the world, and reduction of blood pressure can help to reduce that burden. There is an enormous and ever-expanding body of literature on hypertension, with a 2016 Medline search for hypertension retrieving more than 113,000 publications. Recent guidelines from major societies have been published, and often present conflicting recommendations based on the same data. Using a question-and-answer format, this article reviews some of the recent developments and opinions on management of blood pressure and provides practical suggestions for management in the clinical arena.

Impact of Cocoa Consumption on Inflammation Processes-A Critical Review of Randomized Controlled Trials

Background: Cocoa flavanols have strong anti-inflammatory properties in vitro. If these also occur in vivo, cocoa consumption may contribute to the prevention or treatment of diseases mediated by chronic inflammation. This critical review judged the evidence for such effects occurring after cocoa consumption. Methods: A literature search in Medline was performed for randomized controlled trials (RCTs) that investigated the effects of cocoa consumption on inflammatory biomarkers. Results: Thirty-three RCTs were included, along with 9 bolus and 24 regular consumption studies. Acute cocoa consumption decreased adhesion molecules and 4-series leukotrienes in serum, nuclear factor κB activation in leukocytes, and the expression of CD62P and CD11b on monocytes and neutrophils. In healthy subjects and in patients with cardiovascular diseases, most regular consumption trials did not find any changes except for a decreased number of endothelial microparticles, but several cellular and humoral inflammation markers decreased in patients suffering from type 2 diabetes and impaired fasting glucose. Conclusions: Little evidence exists that consumption of cocoa-rich food may reduce inflammation, probably by lowering the activation of monocytes and neutrophils. The efficacy seems to depend on the extent of the basal inflammatory burden. Further well-designed RCTs with inflammation as the primary outcome are needed, focusing on specific markers of leukocyte activation and considering endothelial microparticles as marker of vascular inflammation.

Cocoa consumption dose-dependently improves flow-mediated dilation and arterial stiffness decreasing blood pressure in healthy individuals

BACKGROUND

Cocoa flavonoids exert beneficial vascular effects and reduce the risk of cardiovascular morbidity and mortality. Nevertheless, the involved mechanisms have not been clarified and no study has yet focused on the dose-response effects.

OBJECTIVES

We aimed to investigate the effects of different doses of cocoa flavonoids on flow-mediated dilation (FMD), endothelin-1 (ET-1), pulse wave velocity (PWV), and SBP and DBP.

DESIGN

According to a randomized, double-blind, controlled, cross-over design, 20 healthy volunteers (1.5% improvement in FMD in 20 individuals: 0.99 at alpha = 0.05) were assigned to receive either five treatments with daily intake of 10 g cocoa (0, 80, 200, 500 and 800 mg cocoa flavonoids/day) in five periods lasting 1 week each.

RESULTS

Cocoa dose-dependently increased FMD from 6.2% (control) to 7.3, 7.6, 8.1 and 8.2% after the different flavonoid doses, respectively (P < 0.0001). Compared with the control, even 80  mg cocoa flavonoids per day increased FMD (P < 0.0001). Cocoa dose-dependently decreased PWV (P < 0.0001). Cocoa intake decreased office blood pressure (BP) (SBP: -4.8 ± 1.03  mmHg, P < 0.0001; DBP: -3.03 ± 1.07 mmHg, P = 0.0011). With respect to control, cocoa ingestion decreased 24-h (P = 0.05) and daytime (P = 0.038) SBP, and 24-h (P = 0.0064), daytime (P = 0.0088) and night-time (P = 0.0352) pulse pressure. Compared with the control, cocoa dose-dependently decreased ET-1 levels [from 17.1 (control) to 15.2, 14.5, 14.2 and 14.1 pg/ml, after the different flavonoid doses, respectively (P for treatment <0.05)]. Compared with the control, significant changes were observed for all doses of flavonoids (ET-1; P < 0.05).

CONCLUSION

Our study showed for the first time that cocoa dose-dependently improved FMD and decreased PWV and ET-1 also by ameliorating office and monitored BP. Our findings are clinically relevant, suggesting cocoa, with very low calorie intake, might be reasonably incorporated into a dietary approach, representing a consistent tool in cardiovascular prevention.

Pharmacokinetic, partial pharmacodynamic and initial safety analysis of (-)-epicatechin in healthy volunteers

(-)-Epicatechin ((-)-EPI), a naturally occurring flavanol, has emerged as a likely candidate for cocoa-based product reported reductions in cardiometabolic risk. The present study aimed to determine the safety, tolerability, pharmacokinetics and pharmacodynamics of purified (-)-EPI administered to healthy volunteers. In this phase I, open-label, two-part single- and multiple-dose study, subjects received either a single dose (n = 9) of 50, 100 or 200 mg or multiple doses (n = 8) of 50 mg daily (q.d.) or twice daily (b.i.d) for 5 days. Blood was collected at 0, 0.5, 1, 2, 4 and 6 h after (-)-EPI administration in the single and multiple dose groups (blood collection repeated in day 5). Samples were analyzed by HPLC-HR-ESI-MS for EPI and metabolite quantification. In the q.d. and b.i.d. groups, blood samples were analyzed for NO surrogates and follistatin levels as well as, platelet mitochondrial complexes I, V and citrate synthase activity levels. (-)-EPI was well tolerated and readily absorbed with further phase 2 metabolism. On day 5, in the q.d. and b.i.d. groups, there were significant increases in plasma nitrite of 30% and 17%, respectively. In the q.d. group on day 5 vs. day 1, platelet mitochondrial complexes I, IV and citrate synthase activities demonstrated a significant increase of ∼92, 62 and 8%, respectively. Average day 5 follistatin AUC levels were ∼2.5 fold higher vs. day 1 AUC levels in the b.i.d. group. (-)-EPI was safe to use, with no observed adverse effects, and our findings suggest that increases in NO metabolites, mitochondrial enzyme function and plasma follistatin levels may underlie some of the beneficial effects of cocoa products or (-)-EPI as reported in other studies.