The intestinal microflora also makes important contributions to our vitamin K, biotin and folate status. New research shows that the microbiome protects the person against chronic diseases such as obesity, diabetes, cancer and cardiovascular diseases.
What we eat has a big impact on the composition and behavior of our gut microflora. The type of bacteria living there and the number of each variety plays a significant role in our health. Apart from our dietary intake, the gut microbiota is impacted by a variety of genetic and environmental factors, including stress and medications. The interaction between all these factors is complex.
Our gut microbiota thrive on fiber-rich foods such as fruits and vegetables, whole grains, nuts and legumes. The fiber encourages the growth and proliferation of healthy microbes. Fiber is degraded by the microflora into short-chain fatty acids, which nourish the cells of the intestinal lining. Animal foods are devoid of fiber so that those consuming a largely meat-based diet will have anaerobic bacteria as the predominant type in their gut. These bacteria are associated with an increased risk of colon cancer. Processed foods often contain added inulin, a fiber from chicory root, as a prebiotic food component to facilitate the growth of a healthy microflora.
Gut microbiome play a role in the development of obesity and diabetes. The type and diversity of micro-organisms living in the gut of persons with obesity and diabetes is different from that of healthy individuals. In studies with mice, scientists have been able to reverse these health conditions by transplanting microflora from the gut of the healthy mice into the gut of mice with obesity or diabetes.
Scientists are looking at ways to alter our microbiome by dietary changes. Patients with type 2 diabetes who were given oligofructose (a sugar that stimulates the growth of certain healthy bacteria) for two years showed improved glucose control and experienced an increased weight loss compared to the control group.
Trimethylamine-N-oxide (TMAO) is a metabolite synthesized by certain gut bacteria from compounds in meat, fish, milk and eggs. TMAO is associated with speeding up the rate of atherosclerosis. By eating less animal products, TMAO levels could be decreased, thereby decreasing the risk of cardiovascular disease.
Scientists are looking into the possibility of screening one’s microbiome to identify people at high risk of cancer and then to make dietary changes that would nurture bacteria that would reduce the risk of cancer.
People often take probiotics (supplements) to restore their colonic microflora after taking antibiotics. The evidence suggests that the probiotics may actually delay the restoration of a person’s microbiome.