Thousands of years ago, the Mayans and Aztecs used the cocoa bean as a form of currency; they believed it had magical properties and was perhaps even divine. Our love affair with chocolate continues, but at least one aspect of chocolate's mystery has recently been revealed.

There is a good bit of evidence showing that eating chocolate is related to a variety of health benefits. People who eat chocolate regularly tend to have a lower risk of stroke and heart attack; they also tend to have lower blood pressure.

Certain bacteria in the digestive tract like chocolate as much as we do.

Even though these benefits are well-documented, the exact reason for them has been unknown. A paper presented recently at the American Chemical Society in Dallas may have solved the mystery.

It appears certain bacteria in the digestive tract like chocolate as much as we do. They eat the chocolate and then ferment it into an anti-inflammatory product that is good for the heart.

Researchers from Louisiana State University (LSU) examined the effects of dark chocolate on the bacteria found in the gut. Three different cocoa powders were tested in a lab study designed to mimic the way chocolate is digested.

“Some components [of cocoa] are not digested but are changed by the microbiome in the gut. The products of these fermentations [are responsible for] some of the benefits attributed to cocoa,” John Finley, lead researcher and Professor of Food Science at LSU, explained in an email.

Cocoa powder contains antioxidant compounds including catechin and epicatechin, as well as a small amount of dietary fiber. Initially, the antioxidants in cocoa are not digested and well absorbed, but when they reach the colon the bacteria there take over and ferment the fiber, breaking it down and creating smaller molecules that are more easily absorbed by the body. These smaller molecules provide the beneficial anti-inflammatory activity so many studies have noted.

The combination of the fiber in cocoa with prebiotics may be what helps create these beneficial anti-inflammatory compounds. Unlike probiotics, prebiotics are not bacteria, but indigestible dietary fiber compounds that provide food for the good bacteria in our digestive system.

Eating a wide variety of fruits, vegetables, whole grains, and legumes provides plenty of soluble fiber to feed the good bacteria and can help the body overcome the effects of undesirable bacteria, such as Clostridia and some E. coli, that cause digestive problems.

The health benefits of dark chocolate may be increased when it is eaten in combination with solid fruits like pomegranates and acai, Finley believes, but this theory has yet to be tested.

Dr. Finley says the message to consumers is, “In moderation chocolate is good for you, and cocoa powder provides a multitude of potential benefits.” When buying chocolate, keep in mind, “Darker is better.”