The machinery in our gut
Taken together, the molecules that are produced by a person's gut bacteria make up what scientists called their "metabolome."
"You can think of the bacteria and other organisms that live in our intestines as machinery in a factory, and you think of the food we eat as the raw materials that are processed in these machines" that ultimately produce an end product, said Dr. James Lewis, a gastroenterologist and professor of medicine at the University of Pennsylvania, who was not involved in the study.
"The metabolome is one example of the end product," Lewis told Live Science.
Gut bacteria has been shown to influence health in many ways. However, it's more likely that the compounds produced by the gut bacteria are what impact our health, rather than the bacteria themselves, he said. These compounds can be beneficial (such as short-chain fatty acids) or harmful (such as trimethylamine oxide), Lewis said.
The "machines" that you turn on more often and the "raw materials" that you bring in may determine whether what's produced is harmful or beneficial, Lewis said.
Although previous research has focused on figuring out which types of bacteria are present in the gut, studying the products of these bacteria is the next logical step in the research, Lewis said.
"To get here, we had to first figure out who's [in the intestines]. Now, we can start thinking about what they're doing," he said.