Short-term increase in fiber alters gut microbiome
Written by Timothy Huzar on April 3, 2021 — Fact checked by Catherine Carver, MPH
Share on PinterestAn increase in fiber can change the microbiome within 2 weeks. Catherine Falls Commercial/Getty Images
- Researchers have previously identified a link between fiber intake and positive health outcomes.
- Fiber promotes a healthy gut microbiome once bacteria metabolize it.
- A recent study found that a 2-week increase in fiber intake significantly altered the gut microbiome.
Researchers have found that a 2-week increase in fiber intake can significantly alter a person’s gut microbiome, including increasing species of bacteria that break down fiber.
However, the quantity of short-chain fatty acids (SCFAs) did not increase. SCFAs are the result of bacteria breaking down fiber, and they have diverse roles within the body.
For instance, SCFAs are used as a source of energy for the cells of the colon and are involved in cell signaling. Some SCFAs also have anti-inflammatory properties and might influence insulin sensitivity and body weight.
The research, which appears in the journal mSystems, lays the groundwork for future studies to explore in more detail the relationship between fiber intake, gut bacteria, and SCFAs.
Benefits of fiber
Fiber plays an important role in human health. For example, a recent review of various meta-analyses found that people who eat the most fiber significantly reduce their chances of dying due to a cardiovascular event.
However, only 1 in 20 people in the United States consume the recommended amount of fiber.
According to Dr. Katrine Whiteson, associate professor of molecular biology and biochemistry, co-director of the University of California, Irvine (UCI) Microbiome Initiative, and co-author of the present study:
“The lack of fiber intake in the industrialized world is starving our gut microbes, with important health consequences that may be associated with increases in colorectal cancer, autoimmune diseases, and even decreased vaccine efficacy and response to cancer immunotherapy.”
The small intestine cannot digest fiber. Instead, according to the authors of the present study, it passes into the colon, where microbes are able to break the fiber down.
This process results in the production of SCFAs. Experts believe they are important for a range of factors affecting a person’s health.
The authors of the present study wanted to study the relationship between a short-term increase in dietary fiber, the makeup of the gut microbiome, and the presence of SCFAs.