March 19, 2014
Gut Bacteria Love Dark Chocolate, And Here’s Why
April Flowers for redOrbit.com - Your Universe Online
For centuries, the health benefits of ingesting dark chocolate have been lauded. Why, however, has remained a mystery, until now. A new study by Louisiana State University (LSU) researchers, whose findings were reported at this week's 247th National Meeting & Exposition of the American Chemical Society, reveals that certain bacteria in the stomach eat the chocolate and ferment it into 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," explained Maria Moore, an undergraduate student at LSU.
"The good microbes, such as Bifidobacterium and lactic acid bacteria, feast on chocolate," she said. "When you eat dark chocolate, they grow and ferment it, producing compounds that are anti-inflammatory." The other bacteria in the gut — including E. coli and Clostridia — are associated with inflammation and can cause gas, bloating, diarrhea and constipation.
"When these compounds are absorbed by the body, they lessen the inflammation of cardiovascular tissue, reducing the long-term risk of stroke," said John Finley, Ph.D., who led the work. This study is the first to investigate the effects of dark chocolate on the various species of bacteria in the stomach, according to Finley.
Three cocoa powders were tested by the team using a model digestive tract. This model was composed of a series of modified test tubes to simulate normal digestion. They then subjected the non-digestible materials to anaerobic fermentation using human fecal bacteria
Containing several polyphenolic, or antioxidant, compounds such as catechin and epicatechin, cocoa powder also has a small amount of dietary fiber. In the stomach, both compounds are poorly digested and absorbed, but when they reach the colon, the desirable microbes take over.
"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.
The combination of cocoa's fiber with prebiotics is likely to improve a person's overall health, said Finley, along with helping to convert polyphenolics in the stomach into anti-inflammatory compounds.
“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 added.
Foods such as raw garlic and whole wheat flour are undigestible by humans, but they contain prebiotics, or types of carbohydrates, that the good bacteria in your gut like to eat. Prebiotics can also be found in dietary supplements.
When chocolate is combined with solid fruits such as pomegranates and acai, even more health benefits can be obtained. Finley said that the next step could be for industry to do just that.