How does Chocolate protect the Heart?


A number of studies have shown cardiovascular benefits of eating flavanol rich cocoa. In this post I will discuss the possible underlying mechanisms of these cardioprotective properties of chocolate as published in a recent review article: Flavanol-rich cocoa, a cardioprotective nutriceutical.

  • Cocoa flavanols as antioxidants. Antioxidants are substances that may protect cells from the damage caused by unstable molecules known as free radicals.Oxidation of low-density lipoprotein (LDL) has been implicated in atherogenesis. Or LDL, a form fat in your blood that plays an important role in harming especially your larger blood vessels can lead to hypertension, lack of oxygen supply to the heart with as complication a hart attack. Antioxidants such as flavanols in chocolate that prevent LDL from oxidizing may reduce atherosclerosis. Although the precise mechanism of flavanol’s antioxidant action has not been agreed upon, research findings do suggest that the consumption of cocoa flavanols in the diet can significantly improve the
    oxidative defense system.
  • Modulation of vascular function. Impaired arterial endothelial function or impaired function of the inner layer of blood vessels has been shown to be a significant early event in atherogenesis and has been associated with an increased cardiovascular risk. Other diseases such as stress, ischemia (short oxygen supply), atherosclerosis, diabetes mellitus, and hypertension, can disrupt endothelial function. As a result, a dysfunctional endothelium may lose its protective effects on the vascular system. The acute consumption of dark chocolate by healthy volunteers have shown the acute dilatation of muscular arteries and an increased arterial elasticity
  • Inhibition of platelets. Platelet aggregation or the forming of small blood cloths is the critical event occurring during the initiation of coronary thrombosis which can lead to cardial infarction. Several studies have provided strong support for the antiaggregatory effects of cocoa flavanols.
  • Antihypertensive effects. The results of 2 separate studies in healthy subjects and later in hypertensives have shown possible benefits of cocoa in blood pressure lowering.This also can be considered as cardioprotective since hypertension leads to an overload of the heart.
  • Anti-infammatory effect. Cocoa flavanols have also been shown to have potential anti-inflammatory activities that are relevant to cardiovascular health. With inflammation, substances are formed which can produce adverse cardiovascular effects.

Now, Dr Shock will never let a change to promote chocolate consumption slip although lack of positive effects are also published on this blog in: Short-term Chocolate Effects on Health.

Moreover, it should also be noted that the evidence for any cardiovascular benefits of cocoa flavanols has been gathered predominantly from short-term and uncontrolled
studies. Therefore, additional research in well-designed, long-term human clinical studies using cocoa would be most helpful in assessing whether flavanol-rich cocoa
could be a potential candidate for the treatment, or possible prevention of cardiovascular disease. The beneficial effects of chocolate also need to be balanced against its high caloric and high fat contents.

ResearchBlogging.org
Mehrinfar, R., Frishman, W.H. (2008). Flavanol-Rich Cocoa. Cardiology in Review, 16(3), 109-115. DOI: 10.1097/CRD.0b013e31815d95e2