A diet rich in natural fiber helps protect the mucus layer of the gut from pathogenic microorganisms, reports a recent study.

Generally, the gut microflora depends on the natural fiber for food. When a person consumes a diet with no or little natural fiber, the organisms in the digestive system starve for food and, as a result, feed on the mucus layer of the gut. When the mucus layer is eroded, it paves way for the invasion of pathogenic bacteria into the walls of the colon.

Mice Experiment With High-Fiber Diet

According to the study published in the journal Cell, the researchers studied the effects of natural fiber deprivation in the digestive system of mice. A group of mice were grown without native microbes in the gut and were later transplanted with 14 bacteria that are usually seen in the human digestive tract.

The investigators were aware of the genetic signature of each organism and hence were able to track the activity of every bacterium introduced in to the gut. The study findings not only help to ascertain the role of natural fiber in diet but also to find solution for other digestive tract disorders.

The researchers fed the mice with different types of food including diet rich in natural fiber, diet with little fiber and diet with no fiber. The mice were then infected with a type of bacteria that cause inflammation, irritation and diarrhea similar to Escherichia coli in humans.

Advantages Of High-Fiber Diet

When the mice were fed with fiber-rich diet, with 15 percent fiber in diet from minimally processed plants and grains, they had no signs of illness as a result of infection. It was found that the organisms in the gut started feeding on the mucus layer when the mice were given diet without fiber.

When the experimental mice were tested with prebiotic fiber, a purified soluble fiber present in processed foods, the researchers found an effect similar to that of a no-fiber diet. It was observed that four bacterial species that exploited the gut environment when the mice were fed with low- or no-fiber diet were those that are capable of breaking down the glycoproteins that form the mucus layer.

High-Fiber Diet For Humans

"While this work was in mice, the take-home message from this work for humans amplifies everything that doctors and nutritionists have been telling us for decades: Eat a lot of fiber from diverse natural sources," said Eric Martens, the lead author of the study at the University of Michigan Medical School in a press release.