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Dark Chocolate: A Tasty Treatment for Cardiovascular Disease

By: Sarah Sharp

October 5, 20090




In a world addicted to both food and the latest health shortcut, dark chocolate may finally be the answer to satisfying these two, seemingly contradictory obsessions.  Chocolate companies such as Hershey’s, Dove, Ghirardelli and Lindt have come to embrace the circulating rumors concerning the positive effects associated with their products.  But the question remains: does dark chocolate really possess the health boosting characteristics it claims when dealing with matters of the heart?



What is Dark Chocolate?


Looking at a shelf in a convenience or grocery store, you will most likely find three general types of chocolate: white chocolate, milk chocolate and dark chocolate. The U.S. Food and Drug Administration provides precise requirements for the classification of both white and milk chocolate; however, no specific restrictions are defined when the title of dark chocolate is placed on the label. For these reasons, you must be careful when calling the chocolate that you are eating “dark.” European parliament, as stated by Rusconi and Conti (2009), classifies dark chocolate as that which has a cocoa content of at least 35% or more, and it is by this definition that we will be using the term dark chocolate.  This cocoa percentage is comparable to the FDA classification of “sweet chocolate.” Unfortunately, sweet chocolate may contain milk, which, as will be discussed later, may actually neutralize any positive effects.


What is Cardiovascular Disease?


Cardiovascular disease is more commonly referred to as heart disease. However, it is important to note that the term “heart disease” covers a multiple of heart related maladies and not just cardiovascular disease. Cardiovascular disease, as defined by the Mayo Clinic, “refers to conditions that involve narrowed or blocked blood vessels that can lead to a heart attack, chest pain (angina) or stroke.” Two of the main risk factors associated with cardiovascular disease are high blood pressure and high blood cholesterol. More detailed information about cardiovascular disease, such as its symptoms, causes and risk factors, can be found through the Mayo Clinic.


What are the rumors?


Type “dark chocolate” into the search engine Google and the first response is an article from the well-respected medical information site WebMD titled: “A Dark Chocolate a Day Keeps the Doctor Away.” This article highlights the results of a study conducted in order to see the effects of dark chocolate consumed on the build up of cholesterol in blood vessels. The flavanoid(antioxidant), epicatechin, contained within dark chocolate was shown to increase the amount of blood flow in arteries – a positive consequence for the heart.  The article goes on to explain to the reader the advanced techniques that have been developed to retain the unique flavanoids found in dark chocolate that produce these positive effects on heart health.


Direct your browser to and you are immediately drawn in by its sleek look and enticing pictures.  Entering into its health section, there are detailed explanations about the consequences, both positive and negative, of chocolate upon the body.  It highlights the antioxidant power of dark chocolate and boosts its effects high above widely accepted antioxidant sources: green tea, blueberries and red wine. These antioxidants work to protect your cells from free radicals, molecules that can adversely affect the structure and activity of healthy, working cells. lists explicitly the Health Benefits of Chocolate. This article explains that studies show that moderate intake of dark chocolate has been proven to lower blood pressure and LDL-cholesterol, both of which determine the overall health of the heart. It also points out that in order to gain any health benefits from chocolate, you must skip over the milk and white chocolate varieties and consume the antioxidant-rich dark chocolate. Also, although it may seem to be a complimentary drink to accompany dark chocolate, milk must be avoided because of the possibility that it may actually neutralize any positive effect gained by the antioxidants. 


Who is feeding these outrageous rumors?


With such positive results and widespread agreement, any logical person should want to find out who is behind these claims. Are these rumors simply a passing fad spread to increase spending on chocolate or is something based in fact?



Upon further investigation into AllChocolate, mentioned previously, a red flag is encountered.  Scroll down to the bottom of the page and click on the Site Sponsors link and you are shown six sponsors, all of which are well respected producers of chocolate, including Hershey’s.  Within the last 5 years, Hershey’s has been at the forefront of research investigating the benefits of antioxidants in chocolate. They have recently come out with a new label (above) for their antioxidant rich chocolate products. In this world where health concerns are shaping the consumption trends of customers, there are obvious reasons for Hershey’s and other chocolate producers to spread “healthy chocolate” rumors.


Dove is making similar claims. Cocoapro, the unique blend of chocolate that is found in Dove’s Dark chocolate, provided superior results compared with other brands of dark chocolate when measuring the positive consequences for hearth health.  Dove Dark chocolate, in particular the individually wrapped Promises, provide not only substantial antioxidants but are also a step above the rest in taste, texture and experience. This article’s direct focus on Dove brings to the surface a question that repeats itself over and over when this information is seen in such a context: are these almost “too good to be true” reports of healthy chocolate simply a highly influential marketing ploy staged by chocolate companies or is what we are reading about actually true?


As they often say, “Behind every rumor there is a little bit of truth.”


Or, in this case, a lot of truth.


Throughout the articles and chocolate reviews documented above there was a shocking commonality: documented research.  It is astonishingly easy to find research studies focused on the antioxidant power of dark chocolate and its effect on cardiovascular health.  Specific investigations into the nature and composition of dark chocolate have allowed researchers to give chocolate companies the go-ahead in advertising the positive benefits of antioxidants in dark chocolate.


Research into the manufacturing of chocolate reveals important steps that must be taken in order to preserve the antioxidant benefits associated with dark chocolate.  A review of the techniques that have been implemented in order to increase the palpability of pure cocoa by McShea et. al. (2008) cautions that, due to the lax naming conventions applied to chocolate and dark chocolate, the consumer must be aware that what they are ingesting may or may not contain the beneficial antioxidants they desire.  Still, the research confirms that, when consuming chocolate rich in antioxidants, there are considerable and significant benefits for the vascular system.


Direct investigation into the effect of dark chocolate on cardiovascular disease has been conducted and the results have yielded significant evidence in support of antioxidant benefits. In a study by Erdman et. al. (2008), a double-blind, cross-over study was conducted on 49 volunteers. It investigated the impact of daily consumption of dark chocolate rich in flavanols (antioxidants) upon cholesterol and blood pressure – two highly notable risk factors for cardiovascular disease. The results were highly significant and influential. A 5.3% decrease in LDL-cholesterol (the kind considered “bad”) was measured as well as an 8.2% decrease in systolic blood pressure which lasted over 8 weeks (Erdman et. al. 2008).  This research presents recognizable scientific evidence that the consumption of flavanol-rich chocolate daily can have healthy heart benefits.


Further investigation into the effect of antioxidants within the body was conducted through experimental methods by comparing concentrations in the bloodstream after the consumption of different types of chocolate (Serafini et. al. 2003). A detailed crossover study was conducted on 12 volunteers who consumed the same amount of antioxidants through three different conditions: dark chocolate, dark chocolate while drinking milk and milk chocolate.  A measurement of epicatechin (an antioxidant) was taken one hour following consumption.  Antioxidant levels within the bloodstream were increased significantly only for the dark chocolate, suggesting that the milk ingested either orally through drinking or as a part of the chocolate inhibits absorption of antioxidants into the bloodstream.  This study brings to light the importance of composition both in the manufacturing stages and ingestion of dark chocolate when recognizing the health benefits associated with cardiovascular disease.



Fortunately for chocolate lovers around the world, there may finally be a desert that we can ingest without a guilty conscious. The benefits associated with antioxidant-rich dark chocolate have been investigated and confirmed to be advantageous for promoting a healthy heart.  However, we must remember that this does not mean that we can spend all day, every day eating dark chocolate to guarantee a healthy heart; only in moderation does dark chocolate produce positive results in reducing the risk factors of cardiovascular disease.
















Erdman Jr., J. W., Carson, L., Kwik-Uribe, C., Evans, E. M., & Allen, R. R. (2008). Effects of

cocoa flavanols on risk factors for cardiovascular disease. Asia Pacific Journal of Clinical Nutrition, 17(S1), 284-287.


McShea, A., Pamiro-Puig, E., Munro, S. B., Casadesus, G., Castell,  M., & Smith, M. A. (2008).

Clinical benefit and preservation of flavonols in dark chocolate manufacturing. Nutrition Reviews, 66(11), 630–641.



Rusconi, M. & Conti, A. Theobroma cacao L., the food of the gods: a scientific approach beyond

myths and claims. Pharmacological Research.


Serafini, M., Bugianesi, R., Maiani, G., Valtuena, S., De Santis, S., & Crozier, A. (2003). Plasma

antioxidants from chocolate. Nature, 424, 1013.









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