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Consumption of flavanol-containing cocoa products has been shown to lower blood pressure (BP), but the minimum dose required to reduce BP is not known. This study aimed to examine the effect of three different doses of cocoa flavanols (CF) on 24-h mean arterial BP. Twenty four hour ambulatory BP (24-ABP) monitoring was performed in 32 men and 20 postmenopausal women with untreated mild hypertension (seated clinic BP >130/85 and <160/100 mm Hg). Participants were randomized and instructed to consume daily a reconstituted cocoa beverage containing 33, 372, 712 or 1052 mg day−1 of CF for 6 weeks in a double-blind, parallel comparison. Seated clinic BP and 24-h ABP were measured at 0, 3 and 6 weeks. Seated clinic BP did not change during the study period. There were significant reductions in 24-h systolic (5.3±5.1 mm Hg; P=0.001), diastolic (3±3.2 mm Hg; P=0.002) and mean arterial BP (3.8±3.2 mm Hg; P=0.0004) at the 1052 mg day−1 CF only. No reduction in BP was seen at any other dose. No evidence of dose–response was seen in this experiment. The highest dose of 1052 mg CF per day was found to significantly lower BP. These results support previous evidence for CF to lower BP, however more research is needed to establish the most effective dose and food matrix.

Objectives: In patients with coronary artery disease (CAD) medically managed according to currently accepted guidelines, we tested whether a 1-month dietary intervention with flavanol-containing cocoa leads to an improvement of endothelial dysfunction and whether this is associated with an enhanced number and function of circulating angiogenic cells (CACs).

Background: Dietary flavanols can improve endothelial dysfunction. The CACs, also termed endothelial progenitor cells, are critical for vascular repair and maintenance of endothelial function.

Methods: In a randomized, controlled, double-masked, cross-over trial, 16 CAD patients (64 ± 3 years of age) received a dietary high-flavanol intervention (HiFI [375 mg]) and a macronutrient- and micronutrient-matched low-flavanol intervention (LoFI [9 mg]) twice daily in random order over 30 days.

Results: Endothelium-dependent vasomotor function, as measured by flow-mediated vasodilation of the brachial artery, improved by 47% in the HiFI period compared with the LoFI period. After HiFI, the number of CD34⁺/KDR⁺-CACs, as measured by flow cytometry, increased 2.2-fold as compared with after LoFI. The CAC functions, as measured by the capacity to survive, differentiate, proliferate, and to migrate were not different between the groups. The HiFI led to a decrease in systolic blood pressure (mean change over LoFI: –4.2 ± 2.7 mm Hg), and increase in plasma nitrite level (mean change over LoFI: 74 ± 32 nM). Applying a mixed-effects linear regression model, the results demonstrated a significant increase in flow-mediated vasodilation and a decrease in systolic blood pressure with increasing levels of CD34⁺/KDR⁺-CACs.

Conclusions: Sustained improvements in endothelial dysfunction by regular dietary intake of flavanols are associated with mobilization of functional CACs. (Effect of Cocoa Flavanols on Vascular Function in Optimally Treated Coronary Artery Disease Patients: Interaction Between Endothelial Progenitor Cells, Reactivity of Micro- and Macrocirculation; NCT00553774).

Flavanols and procyanidins isolated from cocoa have been reported to possess multiple activities potentially relevant to oxidant defenses, vascular function, and immune function. In a combination of in vivo and in vitro studies, we and others have observed that cocoa can be an anti-inflammatory modulator and that compounds in cocoa are capable of modulating eicosanoid production, platelet aggregation, and the pool size of nitric oxide. The present study extends these findings by examining the in vitro effects of cocoa procyanidins on polymorphonuclear cells (PMNs). PMNs, part of the innate arm of the immune system, represent 50-60% of the total peripheral white blood cells and are the first cells to be recruited to the sites of inflammation or injury secondary to bacterial infections. Herein, we demonstrate that certain flavanols and procyanidins isolated from cocoa can moderate a subset of signaling pathways derived from lipopolysaccharide (LPS) stimulation of PMNs, mainly, PMN oxidative bursts and activation markers, and they can influence select apoptosis mechanisms. We hypothesize that flavanols and procyanidins can decrease the impact of LPS on the N-formyl-Met-Leu-Phe-primed PMN ability to generate reactive oxygen species by partially interfering in activation of the mitogen-activated protein kinase pathway.

Hexameric procyanidins inhibit TNFalpha-induced NF-kappaB activation in Caco-2 cells. Most of the physiological actions of high molecular weight procyanidins could be limited to the gut lumen. Transcription factor NF-kappaB plays a central role in inflammation including human intestinal bowel disease. We investigated the capacity of a hexameric procyanidin fraction (Hex) to prevent tumor necrosis factor alpha (TNFalpha)-induced NF-kappaB activation as related to oxidation and membrane interactions. In Caco-2 cells, Hex (2.5-20 microM) inhibited TNFalpha-induced NF-kappaB activation (IkappaB phosphorylation and degradation, p50 and RelA nuclear translocation, and NF-kappaB-DNA binding), inducible nitric oxide synthase expression, and cell oxidant increase. The effects on NF-kappaB activation persist beyond the period of direct exposition of cells to Hex. N-Acetylcysteine and alpha-lipoic acid inhibited TNFalpha-induced oxidant increase but did not affect NF-kappaB activation. In summary, Hex can inhibit NF-kappaB activation by interacting with the plasma membrane of intestinal cells, and through these interactions preferentially inhibits the binding of TNFalpha to its receptor and the subsequent NF-kappaB activation.

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.

Cocoa-derived flavanols and procyanidins have been previously reported to exhibit anti-oxidant and anti-tumor properties. In this study, we have investigated the cellular growth inhibitory effect of chemically-synthesized procyanidin [3-O-galloyl]-(-)-epicatechin-(4beta,8)-(+)-catechin-3-O-gallate (GECGC) on a variety of human cancer cell lines. Among 16 human cancer cell lines tested, GECGC selectively inhibited proliferation of a subset of human cancer cell lines, especially those of short doubling time. In contrast, all 6 normal cell lines tested including human mammary epithelial cells and skin fibroblast were resistant to GECGC's cytotoxicity. Cell cycle analysis and apoptosis assay showed that GECGC increased sub-G(1) population and increased the population of propidium iodide and Annexin V staining cells in GECGC-sensitive cell lines, suggesting that cell growth inhibition by GECGC may be mediated through both apoptotic and non-apoptotic mechanisms. Further characterization of GECGC cytotoxicity on 30 genetically modified cell lines with overexpression or depletion of key proteins involved in cell cycle regulation and signal transduction pathways suggested that GECGC-mediated cell death involves IKKalpha and IKKgamma. Collectively, our observations indicate that synthesized GECGC has selective anti-proliferative effect on human cancer cells and warrant further evaluation as a preventive and chemotherapeutic reagent to human malignancies.

OBJECTIVES: Our goal was to test feasibility and efficacy of a dietary intervention based on daily intake of flavanol-containing cocoa for improving vascular function of medicated diabetic patients. BACKGROUND: Even in fully medicated diabetic patients, overall prognosis is unfavorable due to deteriorated cardiovascular function. Based on epidemiological data, diets rich in flavanols are associated with a reduced cardiovascular risk. METHODS: In a feasibility study with 10 diabetic patients, we assessed vascular function as flow-mediated dilation (FMD) of the brachial artery, plasma levels of flavanol metabolites, and tolerability after an acute, single-dose ingestion of cocoa, containing increasing concentrations of flavanols (75, 371, and 963 mg). In a subsequent efficacy study, changes in vascular function in 41 medicated diabetic patients were assessed after a 30-day, thrice-daily dietary intervention with either flavanol-rich cocoa (321 mg flavanols per dose) or a nutrient-matched control (25 mg flavanols per dose). Both studies were undertaken in a randomized, double-masked fashion. Primary and secondary outcome measures included changes in FMD and plasma flavanol metabolites, respectively. RESULTS: A single ingestion of flavanol-containing cocoa was dose-dependently associated with significant acute increases in circulating flavanols and FMD (at 2 h: from 3.7 +/- 0.2% to 5.5 +/- 0.4%, p < 0.001). A 30-day, thrice-daily consumption of flavanol-containing cocoa increased baseline FMD by 30% (p < 0.0001), while acute increases of FMD upon ingestion of flavanol-containing cocoa continued to be manifest throughout the study. Treatment was well tolerated without evidence of tachyphylaxia. Endothelium-independent responses, blood pressure, heart rate, and glycemic control were unaffected. CONCLUSIONS: Diets rich in flavanols reverse vascular dysfunction in diabetes, highlighting therapeutic potentials in cardiovascular disease.

Previous studies with plant sterols (PS) and cocoa flavanols (CF) provide support for their dietary use in maintaining cardiovascular health. This double-blind, placebo-controlled, cross-over study evaluated the efficacy of daily consumption of a cocoa flavanol-containing dark chocolate bar with added PS on serum lipids, blood pressure, and other circulating cardiovascular health markers in a population with elevated serum cholesterol. We recruited 49 adults (32 women, 17 men) with serum total cholesterol concentrations of 5.20-7.28 mmol/L and blood pressure of < or = 159/99 mm Hg. Following a 2-wk lead-in utilizing the AHA style diet, participants were randomized into 2 groups and instructed to consume 2 cocoa flavanol-containing dark chocolate bars per day with (1.1 g sterol esters per bar) or without PS. Each 419-kJ bar was nutrient-matched and contained approximately 180 mg CF. Participants consumed 1 bar 2 times per day for 4 wk then switched to the other bar for an additional 4 wk. Serum lipids and other cardiovascular markers were measured at baseline and after 4 and 8 wk. Blood pressure was measured every 2 wk. Regular consumption of the PS-containing chocolate bar resulted in reductions of 2.0 and 5.3% in serum total and LDL cholesterol (P < 0.05), respectively. Consumption of CF also reduced systolic blood pressure at 8 wk (-5.8 mm Hg; P < 0.05). Results indicate that regular consumption of chocolate bars containing PS and CF as part of a low-fat diet may support cardiovascular health by lowering cholesterol and improving blood pressure.

There has been growing interest in the potential cardiovascular benefits associated with cocoa consumption. As a result of accurate analytical methodologies, there is evidence to support that the flavanols in cocoa can be absorbed, are bioactive, and may be responsible for the cardiovascular benefits associated with regular cocoa consumption. The flavanols in cocoa exist in a multitude of different stereochemical configurations, thus giving rise to a unique and complex mixture of compounds. Given this complexity, the quantitative analysis of cocoa flavanols in foods can be challenging. While there are published methods suitable for the analysis of these compounds, these methods require sophisticated instrumentation and can be challenging to set up. As such, simpler techniques that measure such things as total phenolic content or antioxidant potential have been used as indicators of flavanol content. However, as these simpler assays are prone to interferences and are not specific for flavanols, these methods are not appropriate for use in studies that aim to examine the physiological effects of cocoa flavanols. It is only through the use of methods that can accurately quantify these flavanols that it will be possible to make meaningful dietary recommendations regarding the consumption of cocoa flavanol containing foods.

Epidemiologic investigations support the hypothesis that regular consumption of flavonoid-containing foods can reduce the risk of cardiovascular diseases (CVD). While flavonoids are ubiquitous in plants, cocoa can be particularly rich in a sub-class of flavonoids known as flavanols. A number of human dietary intervention trials with flavanol-containing cocoa products have demonstrated improvements in endothelial and platelet function, as well as blood pressure. These studies provide direct evidence for the potential cardiovascular benefits of flavanol-containing foods and help to substantiate the epidemiological data. In this review, results from selective published trials with cocoa and chocolate focused on risk for CVD will be discussed along with a study we recently completed evaluating the effects of the daily consumption of flavanol-containing dark chocolate (CocoaVia?) with and without plant sterol esters on CVD markers in a normotensive population with mild hypercholesterolemia. In this study, the daily consumption of flavanol-containing dark chocolate was associated with a significant mean reduction of 5.8 mmHg in systolic blood pressure. Together the results of these human dietary intervention trials provide scientific evidence of the vascular effects of cocoa flavanols and suggest that the regular consumption of cocoa products containing flavanols may reduce risk of CVD.

There has been considerable work on the relationships between nutrition and the immune response, particularly on studies that have focused on adaptive responses. There is increasing recognition of the importance of innate immunity in host protection and initiation of cytokine networks. In this study, we examined the effect of select cocoa flavanols and procyanidins on innate responses in vitro. Peripheral blood mono-nuclear cells (PBMCs), as well as purified monocytes and CD4 and CD8 T cells, were isolated from healthy volunteers and cultured in the presence of cocoa flavanol fractions that differ from another by the degree of flavanol polymerization: short-chain flavanol fraction (SCFF), monomers to pentamers; and long-chain flavanol fraction (LCFF), hexamers to decamers. Parallel investigations were also done with highly purified flavanol monomers and procyanidin dimers. The isolated cells were then challenged with lipopolysaccharide (LPS) with quantitation of activation using CD69 and CD83 expression and analysis of secreted tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, IL-10, and granulocyte macrophage colony-stimulating factor (GM-CSF). The chain length of flavanol fractions had a significant effect on cytokine release from both unstimulated and LPS-stimulated PBMCs. For example, there was a striking increase of LPS-induced synthesis of IL-1beta, IL-6, IL-10, and TNF-alpha in the presence of LCFF. LCFF and SCFF, in the absence of LPS, stimulated the production of GM-CSF. In addition, LCFF and SCFF increased expression of the B cell markers CD69 and CD83. There were also unique differential responses in the mononuclear cell populations studied. We conclude that the oligomers are potent stimulators of both the innate immune system and early events in adaptive immunity.

A single-dose ingestion of flavanol-rich cocoa acutely reverses endothelial dysfunction. To investigate the time course of endothelial function during daily consumption of high-flavanol cocoa, we determined flow-mediated dilation (FMD) acutely (for up to 6 hours after single-dose ingestion) and chronically (administration for 7 days). The study population represented individuals with smoking-related endothelial dysfunction; in addition to FMD, plasma nitrite and nitrate were measured. The daily consumption of a flavanol-rich cocoa drink (3 x 306 mg flavanols/d) over 7 days (n=6) resulted in continual FMD increases at baseline (after overnight fast and before flavanol ingestion) and in sustained FMD augmentation at 2 hours after ingestion. Fasted FMD responses increased from 3.7 +/- 0.4% on day 1 to 5.2 +/- 0.6%, 6.1 +/- 0.6%, and 6.6 +/- 0.5% (each P < 0.05) on days 3, 5, and 8, respectively. FMD returned to 3.3 +/- 0.3% after a washout week of cocoa-free diet (day 15). Increases observed in circulating nitrite, but not in circulating nitrate, paralleled the observed FMD augmentations. The acute, single-dose consumption of cocoa drinks with 28 to 918 mg of flavanols led to dose-dependent increases in FMD and nitrite, with a maximal FMD at 2 hours after consumption. The dose to achieve a half-maximal FMD response was 616 mg (n=6). Generally applied biomarkers for oxidative stress (plasma, MDA, TEAC) and antioxidant status (plasma ascorbate, urate) remained unaffected by cocoa flavanol ingestion. The daily consumption of flavanol-rich cocoa has the potential to reverse endothelial dysfunction in a sustained and dose-dependent manner.

Substantial data suggest that flavonoid-rich food could help prevent cardiovascular disease and cancer. Cocoa is the richest source of flavonoids, but current processing reduces the content substantially. The Kuna living in the San Blas drink a flavanol-rich cocoa as their main beverage, contributing more than 900 mg/day and thus probably have the most flavonoid-rich diet of any population. We used diagnosis on death certificates to compare cause-specific death rates from year 2000 to 2004 in mainland and the San Blas islands where only Kuna live. Our hypothesis was that if the high flavanoid intake and consequent nitric oxide system activation were important the result would be a reduction in the frequency of ischemic heart disease, stroke, diabetes mellitus, and cancer--all nitric oxide sensitive processes. There were 77,375 deaths in mainland Panama and 558 deaths in the San Blas. In mainland Panama, as anticipated, cardiovascular disease was the leading cause of death (83.4 +/- 0.70 age adjusted deaths/100,000) and cancer was second (68.4 +/- 1.6). In contrast, the rate of CVD and cancer among island-dwelling Kuna was much lower (9.2 +/- 3.1) and (4.4 +/- 4.4) respectively. Similarly deaths due to diabetes mellitus were much more common in the mainland (24.1 +/- 0.74) than in the San Blas (6.6 +/- 1.94). This comparatively lower risk among Kuna in the San Blas from the most common causes of morbidity and mortality in much of the world, possibly reflects a very high flavanol intake and sustained nitric oxide synthesis activation. However, there are many risk factors and an observational study cannot provide definitive evidence.

Procyanidins can exert cytoprotective, anti-inflammatory, and anticarcinogenic actions in the gastrointestinal tract. Previous evidence has shown that procyanidins can interact with synthetic membranes and protect them from oxidation and disruption. Thus, in this study we investigated the capacity of a hexameric procyanidin fraction (Hex) isolated from cocoa to protect Caco-2 cells from deoxycholic (DOC)-induced cytotoxicity, cell oxidant increase, and loss of monolayer integrity. Hex interacted with the cell membranes without affecting their integrity, as evidenced by a Hex-mediated increase in the transepithelial electrical resistance, and inhibition of DOC-induced cytotoxicity. DOC induced an increase in cell oxidants, alterations in the paracellular transport, and redistribution of the protein ZO-1 from cell-cell contacts into the cytoplasm. Hex partially inhibited all these events at concentrations ranging from 2.5 to 20 microM. Similarly, Hex (5-10 microM) inhibited the increase in cell oxidants, and the loss of integrity of polarized Caco-2 cell monolayers induced by a lipophilic oxidant (2,2'-azobis (2,4-dimethylvaleronitrile). Results show that the assayed procyanidin fraction can interact with cell membranes and protect Caco-2 cells from DOC-induced cytotoxicity, oxidant generation, and loss of monolayer integrity. At the gastrointestinal tract, large procyanidins may exert beneficial effects in pathologies such us inflammatory diseases, alterations in intestinal barrier permeability, and cancer.

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.

A proteomic analysis of procyanidin B(2) isolated from cocoa against oxidized low-density lipoprotein-induced lipid-laden macrophage formation was performed. Of approximately 400 detected proteins, 12 were differentially expressed as a result of B(2) treatment. They were subsequently identified by liquid chromatography-electrospray ionization-tandem mass spectrometry and the SWISS-PROT database. Further reverse transcriptase-polymerase chain reaction and Western blot analysis revealed that B(2) strongly inhibited arachidonic acid inflammatory reactions, apoptosis, and their coupled mitogen-activated protein kinase and NF-kappaB pathways. To highlight proteins or genes with similar expressed patterns and similarly biological function induced by B(2) in lipid-laden macrophages, a cluster and Kyoto Encyclopedia of Genes and Genomes pathway analysis were performed. The data were mapped to multiple pathways. Further validation of the bioinformatic results revealed that activation of Wnt signaling may contribute to the cardioprotection of B(2). The differentially expressed genes and proteins mentioned above induced by B(2) are through regulating nuclear transcription factors, activating peroxisome proliferator-activated receptor-gamma and inhibiting AP-1 mRNA expressions. These in vitro data help to interpret the beneficial effects of B(2) in reducing the risk of atherosclerosis after consumption of flavonoid-rich foods. Many differentially expressed genes induced by B(2) help to uncover novel targets and may help to target disease interactions in atherosclerosis in the future.

Evidence suggests that flavonoid-containing diets reduce cardiovascular risk, but the mechanisms responsible are unclear. In the present study, we sought to determine the effect of flavanol-rich cocoa on vascular function in individuals with CAD (coronary artery disease). Forty subjects (61+/-8 years; 30 male) with CAD were recruited to a 6-week randomized double-blind placebo-controlled study. Subjects consumed either a flavanol-rich chocolate bar and cocoa beverage daily (total flavanols, 444 mg/day) or matching isocaloric placebos daily (total flavanols, 19.6 mg/day) for 6 weeks. Brachial artery FMD (flow-mediated dilation) and SAC (systemic arterial compliance) were assessed at baseline, 90 min following the first beverage and after 3 and 6 weeks of daily consumption. Soluble cellular adhesion molecules and FBF (forearm blood flow) responses to ACh (acetylcholine chloride; 3-30 microg/min) and SNP (sodium nitroprusside; 0.3-3 microg/min) infusions, forearm ischaemia and isotonic forearm exercise were assessed at baseline and after 6 weeks. FMD, SAC and FBF responses did not differ between groups at baseline. No acute or chronic changes in FMD or SAC were seen in either group. No difference in soluble cellular adhesion molecules, FBF responses to ischaemia, exercise, SNP or ACh was seen in the group receiving flavanol-rich cocoa between baseline and 6 weeks. These data suggest that over a 6-week period, flavanol-rich cocoa does not modify vascular function in patients with established CAD.

Dietary antioxidants contribute to endogenous photoprotection and are important for the maintenance of skin health. In the present study, 2 groups of women consumed either a high flavanol (326 mg/d) or low flavanol (27 mg/d) cocoa powder dissolved in 100 mL water for 12 wk. Epicatechin (61 mg/d) and catechin (20 mg/d) were the major flavanol monomers in the high flavanol drink, whereas the low flavanol drink contained 6.6 mg epicatechin and 1.6 mg catechin as the daily dose. Photoprotection and indicators of skin condition were assayed before and during the intervention. Following exposure of selected skin areas to 1.25 x minimal erythemal dose (MED) of radiation from a solar simulator, UV-induced erythema was significantly decreased in the high flavanol group, by 15 and 25%, after 6 and 12 wk of treatment, respectively, whereas no change occurred in the low flavanol group. The ingestion of high flavanol cocoa led to increases in blood flow of cutaneous and subcutaneous tissues, and to increases in skin density and skin hydration. Skin thickness was elevated from 1.11 +/- 0.11 mm at wk 0 to 1.24 +/- 0.13 mm at wk 12; transepidermal water loss was diminished from 8.7 +/- 3.7 to 6.3 +/- 2.2 g/(h x m2) within the same time frame. Neither of these variables was affected in the low flavanol cocoa group. Evaluation of the skin surface showed a significant decrease of skin roughness and scaling in the high flavanol cocoa group compared with those at wk 12. Dietary flavanols from cocoa contribute to endogenous photoprotection, improve dermal blood circulation, and affect cosmetically relevant skin surface and hydration variables.

Diet patterns are widely recognized as contributors to hypertension. Widely studied potential contributors include intake of sodium, potassium, magnesium, calcium, soluble fiber, ω-3 fatty acids, alcohol, protein, and calories. We add to that list the effect of dietary flavanols present in certain cocoas, which have sufficient activity on vascular nitric oxide to influence blood pressure control. Kuna Indians who live on islands near Panama have little age-related rise in blood pressure or hypertension. On migration to Panama City, blood pressure rises with age, and the frequency of essential hypertension matches urban levels elsewhere. We have identified a specific food that probably makes an important contribution to cardiovascular status. Island-dwelling Kuna drink more than 5 cups of flavanol-rich cocoa per day and incorporate that cocoa into many recipes. Mainland Kuna ingest little cocoa, and what they take is commercially available and flavanol-poor. The flavanol-rich cocoa activates nitric oxide synthase in vitro and in intact humans in the doses that the Kuna employ. Vasodilator responses to flavonoid-rich cocoa are prevented or reversed by the arginine analog, N-nitro-L-arginine methyl ester. Island-dwelling Kuna have a 3-fold larger urinary nitrate:nitrite than do Mainland dwellers. As endothelial dysfunction is central to current thinking on cardiovascular pathophysiology, a food that enhances endothelial function could have broad implications. The list of candidate conditions that might be influenced is impressive, ranging from atherosclerosis and diabetes mellitus to hypertension and preeclampsia, to vascular dementias and end-stage renal disease. The next decade will be interesting.

A new chromatographic approach for separating cocoa procyanidins according to their degree of polymerization (dp) was developed. The technique utilizes diol stationary phase columns operating in normal phase mode with a binary gradient of acidified acetonitrile and methanol-water. Performance of the diol stationary phase was evaluated on an analytical scale utilizing classical chromatographic conditions for the normal phase separation of procyanidins according to dp. The new separation approach was developed on an analytical scale but further extended to the preparative scale. These newly developed analytical and preparative HPLC procedures were successfully applied to the separation and isolation of cacao procyanidins from unfermented cocoa beans. The dp associated with each mol. wt. fraction was determined by MS.