Cocoa, derived from the seeds of Theobroma cacao (Malvaceae), is a common food ingredient with worldwide popularity. Although frequently associated with foods such as chocolate which can contain high levels of fat and sugar, increasing evidence from laboratory, epidemiological, and human intervention studies indicate that cocoa may have beneficial effects in a number of chronic disease conditions including cardiovascular disease and other inflammation and oxidative stress-driven pathologies.
The present special issue on Cocoa and Human Health includes two review articles which critically summarize available data on the cardioprotective and anti- inflammatory activities of cocoa and cocoa-derived phytochemicals, as well as, 5 original studies on topics which range from insulin signaling in cell culture models to metabolomics studies in subjects at high risk for cardiovascular disease. It is meant to serve as a snap-shot, which highlights on-going research on cocoa and human health and points out areas for additional research.
“…cocoa may have beneficial effects in a number of chronic disease conditions…”
In the first review, Arranz et al., provides a needed focus and evaluation of currently-available randomized clinical trials (RCTs) on the cardioprotective effects of cocoa. The authors point out that although smaller, shorter term studies have indicated a beneficial effect of cocoa on a number of important cardiovascular biomarkers, longer-term, larger-scale RCTs are needed. The review by Gu and Lambert concludes that while there is strong evidence for the role of cocoa and cocoa polyphenols as anti-inflammatory agents in metabolic syndrome, the underlying mechanisms remain unclear and the amount of available epidemiological and human intervention data is low.
The studies by Andres-Lacueva et al., Ramos et al., and Noe et al., provide new data on potential underlying mechanisms of action and mechanistic biomarkers for cardioprotective and insulin modulatory effects of cocoa and cocoa polyphenols. The application of metabolomics to the study of the health effects of cocoa represents a significant advance in the field that should aid in the extraction of increasingly rich data sets from both RCTs and laboratory studies. The identification of potential molecular targets such as Akt/AMPK pathway and HNF-3β pathway in human cells lines provide mechanistic leads that can be further studied in vivo.
The last two papers in the supplement by Cady et al., and Panneerselvam et al., provide novel mechanistic data derived from laboratory animal model studies of chronic pain and cardiovascular disease, respectively. These studies are exciting both for the novel mechanisms proposed as well as for the use of relevant animal models.
In summary, cocoa's popularity as food ingredient means that overall human exposure can be quite high. The growing body of data regarding the potential health beneficial effects cocoa indicate that this exposure, in the context of an overall healthy diet and adequate physical activity, may be a net benefit. Significant work remains, however, in better identifying the active principles in cocoa, firmly establishing efficacy in human populations, and developing improved understanding of the underlying mechanisms of action.
Joshua D. Lambert
The Pennsylvania State University
University Park, PA