Adults who ate chocolate more than once a week or more than 3.5 times a month were significantly less likely to develop coronary artery disease than were those who ate less chocolate, according to data from a meta-analysis of more than 300,000 individuals.
Howard Shooter/Thinkstock
Consumption of chocolate has shown beneficial effects on blood pressure and endothelial function, wrote Chayakrit Krittanawong, MD, of Baylor College of Medicine, Houston, and colleagues in the European Journal of Preventive Cardiology. “However, the potential benefit of increased chocolate consumption reducing coronary artery disease (CAD) risk is not known,” they said.
The investigators reviewed data from 5 decades of research, including six studies with a total of 336,289 individuals who reported chocolate consumption. The study participants experienced 14,043 cases of CAD, 4,667 myocardial infarctions, 2,735 cerebrovascular accidents, and 332 cases of heart failure over an average follow-up period of 8.78 years.
Overall, higher chocolate consumption (defined as more than once a week or more than 3.5 times a month) was significantly associated with a decreased CAD risk (pooled risk ratio, 0.94; P < .001) compared to eating no chocolate or eating chocolate less than once a week.
The cardioprotective effects of chocolate may be linked to several nutrients, the researchers noted. Chocolate’s flavenols (epicatechin, catechin, and procyanidins) have demonstrated an ability to reduce myocardial infarct size in an animal study and to reduce platelet aggregation and improve endothelial function in humans with and without CAD. In addition, methylxanthines have demonstrated beneficial effects on cardiovascular function, polyphenols have been shown to facilitate nitric oxide synthesis, and stearic acid has been associated with reduced mean platelet volume, they wrote.
“The benefits of nutrients in chocolate appear promising and chocolate consumption at least once a week may be beneficial for CAD prevention,” the researchers suggested, although they cautioned that the effects of supplemental calories and the impact of fats, milk, and sugar in commercial chocolate must be taken into account.
The study findings were limited by several factors, including the potential dietary confounders such as total energy intake and the type of chocolate consumed (milk, dark, or white) and the relatively homogeneous study population, which included mainly individuals from Europe and the United States.
Additional long-term, double-blind, randomized trials are needed to identify the cardioprotective effects of chocolate, and “studies to determine the role of genetic potential and the beneficial effects of chocolate on CAD may be needed,” the researchers noted.
However, the current study results suggest that “consumption of chocolates at least once a week is associated with a reduction in the risk of CAD,” they concluded.
The study received no outside funding. The researchers had no financial conflicts to disclose.
SOURCE: Krittanawong C et al. Eur J Prev Cardiol. 2020 Jul 23. doi: 10.1177/2047487320936787.