Influence of cocoa extract intake on oxidative, cardiometabolic and psycological status, including a metabolomic approach in middle-aged obese subjects

Abstract

Obesity is associated to a variety of metabolic disorders and psychological disturbances. The improvement of dietary habits and the promotion of physical activity are the principal strategies to combat obesity. Currently, antioxidants are thoroughly being investigated. Cocoa is one of the richest sources of antioxidants, principally flavanols, with healthy properties to prevent cardiovascular disease, endothelial dysfunctions and oxidative stress. In this context, the principal aim of this investigation was to assess if the daily consumption of 1.4 g of cocoa extract (645 mg of polyphenols with 415 mg of flavanols) within ready‐to‐eat meals and consumed under an energy restricted diet (‐15% E) during 4 weeks, could have beneficial effects on the nutritional and the cardiometabolic status, as well as on depression and anxiety symptoms of middle‐aged overweight/obese subjects. In this sense, the specific objectives were: 1) to analyse the effect of the dietary intervention on general nutrition and metabolism; 2) to assess the effects of cocoa extract consumption on anthropometrics and body composition, blood pressure, routine blood biochemical determinations and biomarkers related to oxidative status, endothelial function and inflammation; 3) to investigate the acute effects of cocoa consumption on blood pressure and blood biochemical markers (0, 60, 120 and 180 min), before and after 4 weeks of daily cocoa consumption; 4) to analyse the effect of cocoa intake within ready‐to‐eat meals on depressive and anxiety symptoms, as well as on the peripheral dopaminergic activity; 5) to evaluate plasma and urinary metabolomic profile in order to assess the presence of cocoa derived metabolites. For that purpose, a 4 week, double‐blind, randomised, placebo‐controlled parallel intervention with a simultaneous postprandial sub‐study was carried out. Fifty subjects were recruited, 25 in each group. The intervention consisted on the daily intake of ready‐to‐eat meals supplemented with 1.4 g of cocoa extract and integrated within a 15% energy restricted diet. At the endpoint, 24 subjects completed the study in the control group and 23 subjects in the cocoa group. This investigation showed that an energy restriction of 15% resulted in beneficial outcomes reducing anthropometric and body composition variables, cardiometabolic markers, inflammatory and oxidative markers, and contributed to the reduction of depressive symptoms. Concerning the inclusion of 1.4 g of cocoa extract, a significantly higher reduction of oxidised low‐density lipoprotein‐cholesterol levels was found in cocoa consumers. However, no difference was demonstrated in the oxidative DNA damage between both groups. Interestingly, the daily consumption of the cocoa extract during 4 weeks revealed a higher reduction of the postprandial systolic blood pressure response compared to the control group, suggesting an adaptive effect over time. On the other hand, the consumption of cocoa extract during 4 weeks did not induce a direct effect on Beck Depression Inventory. However, pHVA, which reflects dopaminergic activity in the brain, showed a greater increase in cocoa consumers compared to the control group. In cocoa group, pHVA was negatively associated with the reduction of depressive symptoms, suggesting the implication of cocoa on psychological behaviour. Finally, the higher presence of cocoa derived metabolites in plasma and urine on cocoa consumers suggested the adequate adherence of the volunteers, as well as the bioavailability of cocoa compounds within the meals.