We all know that we should probably be eating more fiber, but what exactly is dietary fiber and how do we metabolize it? Now, scientists are taking a closer look, showing exactly how fiber can benefit our bodies.
Trillions of bacteria live in our intestines. In fact, there are about ten times more bacterial cells in the average person's body that human ones. Known as "microbiota," these bacteria are central to our metabolism and well-being. That's why the researchers decided to take a bit of a closer look at these bacteria.
More specifically, the scientists found that one group of gut bacteria, called Bacteroidetes, digest complex sugars known as xyloglucans. These sugars make up about 25 percent of the dry weight of dietary fruit and vegetables, including lettuce, onion, eggplant and tomatoes. The scientists examined a particular gene sequence that allows Bacteroidetes to carry out this function. In fact, about 92 percent of the population harbors bacteria with a variant of the gene sequence.
"It's been appreciated for a long time that our symbiotic gut bacteria provide us with greatly expanded abilities to digest dietary fiber," said Eric Martens, one of the researchers, in a news release. "However, the precise details of how this happens remain largely unexplored."
Understanding exactly how these bacteria digest complex carbohydrates can help with studies on a wide range of nutritional issues. These include probiotics and prebiotics.
"In this study, we took an empirical approach to decipher how one model gut bacterium digests one type of fiber that is abundant in the foods we eat," said Martens in a news release. "We were subsequently able to fit our findings into a much larger picture because of the existing data that the Human Microbiome Project has already gathered. It is really an example of synergy between separate approaches that ultimately help us see the big picture."
The findings reveal a little bit more about exactly how we digest produce. This, in turn, could help with future nutritional studies that could help us learn more about what we should eat in the future.
The findings are published in the journal Nature.
