Less than 10% of Americans consume adequate dietary fiber, a key component for maintaining gut health and preventing diseases, including colorectal cancer. On average, adults in the United States consume approximately 17 grams of fiber daily, which is significantly below the recommended intake. Men consume less than 50% of the necessary amount, while women reach just under 70% of their required intake. This dietary shortfall has prompted further research into the vital role of fiber in health maintenance.
Fiber is crucial for a healthy diet, aiding in the prevention of constipation and promoting overall gut well-being. A balanced diet rich in fiber includes fruits, nuts, seeds, vegetables, and whole grains. Fruits such as avocados, apples, pears, and raspberries are excellent sources of fiber. Similarly, nuts and seeds contribute significantly to fiber intake. Vegetables like legumes, potatoes, sweet potatoes, broccoli, and squashes are particularly rich in fiber, as are whole grain foods such as freekeh, bulgur wheat, and brown rice.
Beyond aiding digestion and weight management, recent studies highlight fiber’s potential in reducing cancer risk. Research indicates that two byproducts of fiber digestion—short-chain fatty acids (SCFAs) such as propionate and butyrate—may alter gene expression to reduce cancer risk. When gut bacteria break down dietary fiber, these SCFAs are produced and can act on genes to inhibit cancer growth.
“Regardless of the findings from this study, we should be aiming for the [UK] recommendations of 30 grams of fiber per day every day. Unfortunately, few people actually meet these recommendations. The findings of the study add to the already known evidence base that fiber is crucial for health both in terms of human health and the gut microbiome which directly affects our colonic [gut] health.” — Eamon Laird
The human gut microbiome comprises millions of bacteria and microorganisms that facilitate food digestion. Adequate fiber intake increases SCFA production in the gut, which may help prevent colorectal cancer by supporting healthy gene regulation. This connection underscores the integral link between diet and health.
“Eating enough fiber increases SCFA production in the gut, which may help prevent colorectal cancer by supporting healthy gene regulation. It’s a clear reminder of how closely diet and health are linked. [It] opens exciting doors for using diet and gut health to influence gene activity and prevent disease.” — Şebnem Ünlüişler
The study focuses on how SCFAs like propionate and butyrate influence gene activity. They can modify histones—the proteins that package DNA—making the DNA more accessible and allowing SCFAs to activate or deactivate certain genes based on cell type and conditions.
“The research focuses on short-chain fatty acids (SCFAs) like propionate and butyrate, which are produced when gut bacteria break down dietary fiber. These SCFAs can influence the activity of both cancer-promoting (proto-oncogenes) and cancer-suppressing (tumor-suppressor) genes by modifying histones, the proteins that help package DNA. By making the DNA more accessible, SCFAs can turn certain genes on or off, depending on the cell type and conditions.” — Şebnem Ünlüişler
However, while promising, these findings arise from a controlled study environment. Real-world applications require further exploration to understand how typical diets and lifestyles might affect these results.
“This is a well-run and comprehensive cell study with good methodologies but limited in scope — there are further questions to ask with many cell line variations and also real-life scenarios — the typical diet and lifestyle will have major effects, and it is unknown if these compounds still display these potential effects in the field, so to speak.”
Leave a Reply