Scientists have uncovered new evidence showing how fiber in our diet can help fight cancer at the genetic level, offering fresh motivation to increase consumption of foods like beans, nuts, and leafy vegetables. The research, published in Nature Metabolism, reveals for the first time how compounds produced during fiber digestion can directly influence which genes are turned on or off in our cells.
“We found a direct link between eating fiber and modulation of gene function that has anti-cancer effects, and we think this is likely a global mechanism because the short-chain fatty acids that result from fiber digestion can travel all over the body,” explains Michael Snyder, PhD, Stanford W. Ascherman, MD, FACS Professor in Genetics.
A Complex Chain of Events
The research team traced the effects of two compounds – propionate and butyrate – that are produced when gut bacteria digest fiber. These compounds were found to make specific changes to genes that control cell growth and programmed cell death, processes that are critical in preventing cancer development.
The findings come at a crucial time, as less than 10% of Americans consume the recommended amount of fiber. “It is generally the case that people’s diet is very fiber poor, and that means their microbiome is not being fed properly and cannot make as many short-chain fatty acids as it should,” Snyder notes. “This is not doing our health any favors.”
Cancer Prevention Implications
The research reveals these fiber-derived compounds can influence genes in both healthy cells and cancer cells, suggesting potential implications for both prevention and treatment. The team examined effects in human colon cancer cells, healthy human cells, and mouse intestines, finding consistent patterns of genetic changes that could help suppress tumor development.
“By identifying the gene targets of these important molecules we can understand how fiber exerts its beneficial effects and what goes wrong during cancer,” says Snyder. The findings could be particularly relevant given rising rates of colon cancer in younger adults, potentially opening new avenues for research into how dietary interventions might complement existing cancer treatments.
The research suggests increasing consumption of fiber-rich foods like beans, nuts, cruciferous vegetables, and avocados could have more profound health benefits than previously understood. These foods help nourish beneficial gut bacteria that produce the compounds shown to influence gene function throughout the body.