Louisiana State University researchers have solved the mystery behind the much touted health benefits of dark chocolate. The researchers say that certain bacteria in the stomach act on the chocolate to produce anti-inflammatory compounds that are good for the heart.

"We found that there are two kinds of microbes in the gut: the 'good' ones and the 'bad' ones," Maria Moore, an undergraduate student and one of the study researchers, said in a press release. "The good microbes, such as Bifidobacterium and lactic acid bacteria, feast on chocolate. When you eat dark chocolate, they grow and ferment it, producing compounds that are anti-inflammatory."

John Finley, Ph.D., study lead, said that when the body absorbs the compounds it lessens the inflammation of cardiovascular tissue, which reduces the long-term risk of stroke.

On the other hand, the bad bacteria in the gut like Clostridia and some E. coli cause inflammation, gas, bloating, diarrhea and constipation.

Finley said that this was the first study to observe the effects of dark chocolate on various types of bacteria in the stomach.

For the study, the researchers used a model digestive tract to test three cocoa powders. The model comprised of a series of modified test tubes that simulated normal digestion. Finley said that the non-digestible materials were then subjected to anaerobic fermentation using human fecal bacteria.

He said that cocoa powder (ingredient in chocolate) comprises of several polyphenolic/antioxidant, compounds like catechin and epicatechin, and a small amount of dietary fiber. The compounds are poorly digested and absorbed until they reach the colon, where microbes help convert them into anti-inflammatory compounds.

"In our study we found that the fiber is fermented and the large polyphenolic polymers are metabolized to smaller molecules, which are more easily absorbed. These smaller polymers exhibit anti-inflammatory activity," Finley said.

Health benefits enhance when dark chocolates is combined with solid fruits like pomegranates and acai.

Combining fiber in cocoa with prebiotics improves a person's overall health and helps convert polyphenolics in the stomach into anti-inflammatory compounds. Prebiotics are carbohydrates found in foods like raw garlic and cooked whole wheat flour, and dietary supplements.

"When you ingest prebiotics, the beneficial gut microbial population increases and outcompetes any undesirable microbes in the gut, like those that cause stomach problems," Finley said.

The findings were presented at the 247th National Meeting & Exposition of the American Chemical Society (ACS).