Bacteria behind dark chocolate’s health benefits - researchers

A study team from Louisiana State University said that indigestible cocoa polyphenols promoted growth of anti-inflammatory compounds in the stomach, which were good for the heart.

Maria Moore, an undergraduate student and one of the study’s researchers, said: “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.”​

The researchers presented their findings at the 247th National Meeting & Exposition of the American Chemical Society (ACS), at the Dallas Convention Center last week. The published article is due in the coming months.

Cocoa powder analysis​

Some portions of cocoa powder in chocolate are digested and absorbed in the stomach and small intestine but others are not. It was previously unclear whether the portion that was not digested by humans was beneficial to health.

To test the possible positive effects, the research team analyzed three cocoa powders in a model digestive tract. Non-digestible compounds in the cocoa powder such as catechin, epicatechin and fiber were subjected to anaerobic fermentation using human fecal bacteria.

Anti-inflammatory activity​

Study lead author John Finley explained the findings: “When these compounds are absorbed by the body, they lessen the inflammation of cardiovascular tissue, reducing the long-term risk of stroke,”​

“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.”​

He told ConfectioneryNews that the finding provided support for benefits of what was previously considered non-digestible.

We asked him why the research was conducted on cocoa powder and not cocoa butter or even dark chocolate itself.

“Fat would have made the research more difficult because of the mess it creates. Both fat and sugar are actually irrelevant because they are digested and absorbed before the material gets to the colon which is where the microbes live,”​ he said.

Enhancing the effects​

The study author added that including more fiber in dark chocolate products or adding solid fruits like pomegranates and acai could enhance the positive effects. Prebiotics were identified as another possible addition.

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

The study was supported by the Louisiana State College of Agriculture and a Louisiana AgCenter Undergraduate Research Grant. The research team is seeking funds to continue its work.