Calling all Choco-holics! All Hope is Not Lost!

A systematic review of and meta-analysis of 18 randomized controlled trials (RCTs) indicates that compounds in cocoa can actually benefit your cardiovascular system.

The compounds are known as flavanols, which are a sub-class of flavanoids, which are the botanical elements which give foods like cranberries and blueberries their superpowers. The flavanoids in cocoa are also what make it bitter. But what interested researchers from Brown University was the evidence that consumption of flavanol-rich cocoa products was associated with improvements in specific circulating biomarkers of cardiometabolic health. They gathered up 1,139 volunteers, some placebos with negligible cocoa flavanol content, and got to work.

“Our meta-analysis of RCTs characterizes how cocoa flavanols affect cardiometabolic biomarkers, providing guidance in designing large, definitive prevention trials against diabetes and cardiovascular disease in future work,” said corresponding author Dr. Simin Liu, professor and director of the Center for Global Cardiometabolic Health at Brown University who worked with epidemiology graduate student and lead author Xiaochen Lin. “We found that cocoa flavanol intake may reduce dyslipidemia (elevated triglycerides), insulin resistance and systemic inflammation, which are all major subclinical risk factors for cardiometabolic diseases.”

The improvements were not major – cocoa is no health-enhancing superfood, to be sure. But the data showed clear potential beneficial effects of flavanol-rich cocoa on cardiometabolic health. The sweet spot was for those who consumed between 300 and 600 milligrams of flavanols per day. These subjects enjoyed significant declines in blood glucose and insulin, and HOMA-IR, another indicator of insulin resistance. Additionally, they saw an increase in “good” cholesterol. Those consuming even higher doses saw a drop in their triglyceride levels, but lost the boost in “good” cholesterol; those with lower doses only benefited from the cholesterol boost. The results were the same whether the cocoa was consumed in liquid or solid form.

“The treatment groups of the trials included in our meta-analysis are primarily dark chocolate — a few were using cocoa powder-based beverages,” Lin said. “Therefore, the findings from the current study apparently shouldn’t be generalized to different sorts of chocolate candies or white chocolates, of which the content of sugar/food additives could be substantially higher than that of the dark chocolate.”

The authors concluded that there was an “urgent need for large, long-term RCTs that improve our understanding of how the short-term benefits of cocoa flavanol intake on cardiometabolic biomarkers may be translated into clinical outcomes.”