Mars Inc. packs 350 milligrams of cocoa flavanols into its 30-calorie a day CocoVia daily supplements.

WSJ: Heart-Healthy Chocolate: Dark and Bitter Treat

According to the bottle's label, every two pills contain at least 450 milligrams of pure plant flavanols.

WSJ: Heart-Healthy Chocolate: Dark and Bitter Treat

Most of the brands don't have lab tests on the amount of flavanols, so there's no way to make a comparison.

WSJ: Heart-Healthy Chocolate: Dark and Bitter Treat

Most chocolate isn't labeled with milligrams of flavanols and there's no industry or scientific standard yet for measuring flavanols in chocolate.

WSJ: Heart-Healthy Chocolate: Dark and Bitter Treat

Also, Hershey's research has shown that baking a chocolate cake with baking soda, which is an alkaline, destroyed flavanols but nutrients were retained when using baking powder.

WSJ: Heart-Healthy Chocolate: Dark and Bitter Treat

Hershey's Extra Dark contains 420 milligrams of flavanols in a 1.4-ounce serving and Hershey's cocoa contains 210 milligrams of flavanols per tablespoon, says Debra Miller, director of nutrition at Hershey Co.

WSJ: Heart-Healthy Chocolate: Dark and Bitter Treat

To drink your flavanols, Choffy is specially milled 100% cocoa and roasted to taste good when brewed like coffee ideally in a French press, says Jason Sherwood, co-founder of Choffy LLC, Vancouver, Wash.

WSJ: Heart-Healthy Chocolate: Dark and Bitter Treat

Two medical websites, Medical News Today and WebMD, not only took the story seriously, but also bought into the explanation that the effect is caused by flavanols, which are found not just in cocoa, but also in red wine and green tea.

FORBES: Chocolate Makes Us Smarter. Or Does It?