Cosmeceutical Critique: Cocoa and ChocolateDr. Leslie Baumann
Volume 36, Issue 3, Page 20 (March 2005)
One need look no further than the billions of dollars reaped yearly by the candy industry to know that chocolate is one of the world's best-loved foods.
The plethora of positive health reports about chocolate in recent years is also music to the ears of chocolate lovers and makers. A spate of studies within the last decade suggest that the cocoa plant and its derivatives, by virtue of polyphenolic constituents, confer significant antioxidant benefits, particularly in terms of curbing cardiovascular inflammation. Indeed, cocoa and chocolate are rich sources of flavonoids (Curr. Opin. Lipidol. 2002;13:41-9). Of course, such studies (Lancet 1996;348:834; BMJ 1998;317:1683-4; Phytochem. Rev. 2002;1:231-40) were eagerly picked up by and funneled through the mass media to the public for general consumption, as it were, potentially contributing to mistaken beliefs.
The word cocoa is an adaptation of the word cacao, used by Spanish colonists in the mid-1500s and derived from kakaw in the Olmec and Mayan languages. Chocolate comes from the Nahuatl (Aztec language) word cacahuatl, which is derived from the Olmec/Mayan expression for the derivative of the cocoa plant. During this period, the Spanish brought cocoa to Europe, and, as it spread throughout the continent, the medicinal use of the cocoa plant and its derivatives joined the Western canon (J. Nutr. 2000;130 [suppl. 8s]:s2057-72).
Since that time, more than 100 medicinal uses for cocoa/chocolate have been described for several conditions, including anemia, bowel dysfunction, mental fatigue, poor breast milk production, tuberculosis, fever, gout, kidney stones, reduced longevity, and poor libido/low virility (J. Nutr. 2000;130[suppl. 8s]:s2057-72). Also since the mid-1500s, cocoa and its derivatives have been considered delicacies in many regions (J. Am. Coll. Nutr. 2001;20:s436-39).
Preparations of the cocoa plant's beans, bark, oil, leaves, and flowers are used to treat cutaneous conditions such as burns, cuts, and skin irritations (J. Nutr. 2000; 130:s2057-72). Despite a long history of medical and dietary use, however, cocoa and chocolate only recently have been recognized by the medical establishment for significant potential health benefits (J. Am. Coll. Nutr. 2001;20[suppl. 5]:s436-9).
Much of the recent evidence touting the beneficial health effects of cocoa and chocolate is, understandably, derived from in vivo as well as in vitro evaluations of their ingestion. From a dermatologic perspective, there is more documentation on chocolate as an allergen than as a potential treatment component. However, extensive research into the possible health benefits of this much cultivated plant is warranted as it has been found to share several of the same antioxidant components as red wine, green tea, and grape seed extract.
In fact, researchers used high-performance liquid chromatography mass spectrometry (HPLC/MS) techniques that confirmed the presence of a complex series of procyanidins in raw cocoa and certain chocolates (J. Agric. Food Chem. 1999;47:490-6).
In other research, the monomeric flavonols (-)-epicatechin and (+)-catechin, among the potent components of green tea, along with oligomeric procyanidins formed from these monomeric units, have been identified as components of cocoa and many of its derivatives (Am. J. Clin. Nutr. 2002;76:798-804).
Interestingly, researchers analyzing the antioxidant capacities of the phenolic phytochemicals in cocoa (which include theaflavin, epigallocatechin gallate, resveratrol, and procyanidin) found that cocoa contained significantly higher levels of total phenolics and flavonoids per serving than—in descending order of antioxidant strength—red wine, green tea, and black tea, as measured using radical-scavenging assays. The investigators concluded that the higher antioxidant potency of cocoa confers more health benefits than tea and red wine (J. Agric. Food Chem. 2003;51:7292-5).
Fighting Free Radicals
The antioxidant activities of cocoa flavonoids have been further supported by a functional genomic analysis of the effects of epicatechin and polyphenolic cocoa extract in the human colon adenocarcinoma cell line Caco-2, which demonstrated changes in gene expression and messenger RNA levels consistent with antioxidant exposure (J. Nutr. 2004;134:2509-16). The signs of antioxidant potential in cocoa and chocolate are present throughout much modern research of the plant and its derivatives. Cocoa's main flavonoids have been associated with beneficial effects, including antioxidant protection and modulation of vascular homeostasis (J. Am. Diet. Assoc. 2003;103:215-23).
Cocoa and chocolate are associated with a reduced risk of degenerative conditions, such as cardiovascular disease, and mortality (Dev. Immunol. 2002;9:135-41; Am. J. Clin. Nutr. 2002;76:798-804). Such conclusions are typically ascribed to the phytochemical constituents of the plant and its products. Chocolate is rich in polyphenols—particularly procyanidins, which are said to confer cardioprotective activity (J. Nutr. 2000;130[suppl. 8s]:s2115-9). Indeed, the most significant overarching conclusion from recent studies seems to be that human cellular responses to oxidative stress have been positively affected by the polyphenols in cocoa extract (J. Nutr. 2004;134:2509-16).
One of the studies that excited the lay public showed that plasma levels of epicatechin increased significantly, promoting free-radical scavenging, in a dose-response manner 2 hours after the consumption of chocolate (J. Nutr. 2000;130[suppl 8s]:s2115-9).
One study considering the postingestion ex vivo effects of cocoa procyanidins showed suppression of unstimulated and stimulated platelet activation in whole blood, which the investigators believe may partially account for the cardioprotective effects ascribed to dietary polyphenols (J. Nutr. 2000;130[suppl. 8s]:s2120-6). Dietary flavonols and their related oligomers, the procyanidins, by stimulating the secretion of tumor necrosis factor-a, also are believed to impart antimicrobial and antitumorigenesis effects (Dev. Immunol. 2002;9:135-41).
Noting the relatively high lipid content of chocolate and the fact that one-third of the lipid in cocoa butter is composed of stearic acid, a fat that exerts a neutral cholesterolemic response, some researchers have concluded that cocoa and chocolate contribute to the trace mineral absorption essential for optimum functioning of all biologic systems and vascular tone.
Some health professionals have consequently acknowledged the role that components of cocoa products, particularly chocolate, can play in nutrition and health and have responded by recommending the consumption of various phytochemical-rich foods, including moderate amounts of dark chocolate (J. Am. Diet. Assoc. 2003; 103:215-23).
Others are less specific, noting that the cardiovascular, vascular endothelial, and anti-inflammatory benefits of flavonols can be obtained nutritionally in significant amounts from appropriately produced cocoa and chocolate foods, which are believed to confer their benefits when consumed as part of a healthful balanced diet (Nutr. Today 2002;37:103-9).
While the flavonols and procyanidins isolated from cocoa exhibit strong antioxidant properties in vitro, some chocolate products contain essentially no flavonoids, and others are quite high in flavonoid content (Curr. Opin. Lipidol. 2002;13:41-9). So when considering the recent and popular conclusions that chocolate can be a component of a healthy diet, it is important to note that not all chocolate products are created equal.
Investigators have approximated the flavonoid-rich chocolate needed to exert acute and chronic effects are 38 g and 125 g, respectively (Curr. Opin. Lipidol. 2002;13:41-9).
Though cocoa and chocolate are usually considered innocuous if not beneficial (and, of course, tempting), chocolate, at least, has been known to act as a rosacea trigger in some people and is otherwise implicated in some allergic reactions.
In a study of factors aggravating atopic dermatitis, 195 Japanese adult patients with atopic dermatitis evaluated in the hospital setting were challenged with suspected foods.
Chocolate was found to be among the average of 1.7 challenge-positive foods confirmed in 86 of the patients (J. Dermatol. 2003;30:91-7).
However, potential skin benefits have been reported. In a recent study, investigators found that the pentameric and octameric procyanidin fractions of cocoa inhibited the proliferation of human dermal microvascular endothelial cells, and thus, angiogenesis, in vitro.
The authors speculated that if such effects are applicable in vivo, a beneficial effect from cocoa procyanidins may be seen in certain neoplasias (Exp. Biol. Med. 2004;229:765-71).
Benefits Are Skin Deep
Cocoa butter is used frequently in topical OTC products but will be the focus of an upcoming article. Cocoa and chocolate could very well be included in an increasing array of untested, unregulated products, but chocolate has made its biggest dermatologic splash by its use as one of the featured attractions in trendy spas.
In chocolate facials, body wraps, and similar treatments, chocolate has been touted for its smoothing, firming, and even contouring effects. I've been too busy working on my new book to have a chocolate facial but certainly have consumed my share of Godiva chocolates!
As is often the case regarding cosmeceutical ingredients discussed in this column, more research is necessary to ascertain the actual benefits that cocoa and cocoa-containing products confer to the skin.
The wealth of studies in recent years on the antioxidant potency of cocoa and chocolate is compelling.
The potential far-reaching systemic benefits of the cocoa plant cannot necessarily be extrapolated to the skin, so randomized placebo-controlled clinical trials with cocoa-containing topical products are desirable.
That said, there very well could be at least a placebo effect occurring as result of the use of chocolate in spa facial treatments.
DR. BAUMANN is director of cosmetic dermatology at the University of Miami. To respond to this column or to suggest topics for future columns, write to Dr. Baumann at our editorial offices via e-mail at firstname.lastname@example.org.
© 2005 Elsevier Inc. All rights reserved.