Fiber protects against deterioration of the inner colonic mucus layer, scientists find
03 Jan 2018 --- The importance of maintaining healthy gut bacteria has been well established as has the importance of consuming enough dietary fiber, which can influence your weight, blood glucose level and sensitivity to insulin. The latest research from Sahlgrenska Academy, published in the journal Cell Host & Microbe, shows that colonic health is also affected by the amount of fiber consumed.
The researchers found that mice put on a low-fiber diet developed defects in the inner colonic mucus layer after only three days characterized by increased bacterial penetrability, a potential risk for inflammatory bowel disease and other disorders.
“Our results demonstrate that the inner mucus layer separate gut bacteria from the body’s cells,” Gunnar C. Hansson, Professor of Medical and Physiological Chemistry and director of the study, says. “We clearly illustrated the rapid, process by which the mucus layer responds to dietary modifications and subsequent bacterial changes.”
In a second experiment, the mice fed a fiber-depleted diet received a transplant of gut bacteria from a normally fed animal and regained some of the lost protective effects. The researchers found that a dietary supplement of friendly bifidobacteria stimulated growth of the mucus layer but did not prevent bacteria in the gut microbiota from approaching the body’s cells. A supplement of inulin, a type of dietary fiber, addressed the latter problem but not the former.
“Low-fiber diets alter bacterial composition and influence what they produce,” Professor Hansson says. “The result can be greater penetrability that affects the body’s cells.”
“Average fiber consumption has declined drastically in developed countries over the past few decades,” says Fredrik Bäckhed, Professor of Molecular Medicine, who studies the role of gut bacteria in metabolic disorders.
Fiber supplements as a method of treatment need to be investigated further, the researchers report, adding that simply enriching food with refined fiber is not recommended before more has been learned about its complex interplay with food, bacteria and the body’s cells.
