Good news, chocolate lovers: The sweet treats you indulge on may be good not only for your soul, but for your heart. A recent meta-analysis published in the European Journal of Preventive Cardiology concluded that “the consumption of chocolates at least once a week is associated with a reduction in the risk of CAD [coronary artery disease].”
Authors Chayakrit Krittanawong et al. based their findings on the analysis of six prior studies composed of 336,289 individuals with a median follow-up time of 8.78 years. Of those nearly 337,000 subjects, 21,777 developed some form of heart disease; the breakdown was as follows:
- 14,043 cases of CAD;
- 4,667 myocardial infarctions;
- 2,735 cerebrovascular accidents;
- 332 cases of heart failure
Based on their findings, the authors concluded, “Compared with the consumption of no or less than one time per week, higher chocolate consumption (>1 time per week or >3.5 times per month) was associated with a decreased risk of CAD.”
The reasons behind chocolate’s apparent impact on CAD are varied. One factor may be the flavanols (e.g. epicatechin, catechin) present in chocolate. The meta-analysis authors noted these flavanols “have been shown to reduce myocardial infarct size in one animal study, to reduce platelet aggregation and improve endothelial function in several randomized controlled trials of healthy individuals or people with CAD.”1
Additionally, methylxanthines found in chocolate have shown beneficial effects on cardiovascular function.2 Polyphenols found within chocolate have also “been shown to facilitate nitric oxide synthesis”3, while steric acid can reduce mean platelet volume.4
The authors, while concluding that chocolate consumption at least once per week may have beneficial effects on cardiovascular health, did note that consumers should remain aware of some unfavorable effects of chocolate as well, namely that some chocolate can be high in fat and especially sugar. The authors also noted that the vast majority of subjects within the studies cited were within the U.S. and Europe, thus limiting the scope of the results; just 1,216 subjects, all from Australia, came from outside the U.S. and Sweden.
Due to these caveats, the authors suggest, “Further long-term, double-blind, randomized controlled trials are needed to determine the underlying physiological mechanisms of the cardioprotective effects of chocolate and the association with CAD risk. Future studies to determine the role of genetic potential and the beneficial effects of chocolate on CAD may be needed.”
- Rull G, Mohd-Zain ZN, Shiel J, et al. “Effects of high flavanol dark chocolate on cardiovascular function and platelet aggregation.” Vasc Pharmacol 2015; 71: 70–78.
- Sansone R, Ottaviani JI, Rodriguez-Mateos A, et al. “Methylxanthines enhance the effects of cocoa flavanols on cardiovascular function: randomized, double-masked controlled studies.” Am J Clin Nutr 2017; 105: 352–360.
- Schini-Kerth VB, Auger C, Kim JH, et al. “Nutritional improvement of the endothelial control of vascular tone by polyphenols: role of NO and EDHF.” Pflugers Arch: Eur J Physiol 2010; 459: 853–862.
- Kelly FD, Sinclair AJ, Mann NJ, et al. “A stearic acid-rich diet improves thrombogenic and atherogenic risk factor profiles in healthy males.” Eur J Clin Nutr 2001; 55: 88–96