Our gut flora consists of trillions of bacteria living in our digestive tract. Its function is so important that it could be considered an organ. Recent studies analyzed the gut flora of people across multiple countries and continents and identified two enterotypes. Enterotypes correlate with our diet and can change as our diet changes. Diets rich in animal protein and saturated fat are associated with the Bacteriodes enterotype, while diets rich in healthy carbohydrates are associated with the Prevotella enterotype.
When our gut bacteria process the food we ingest, by-products are created. Examples of potentially harmful by-products created in our gut from a diet rich in animal products include: hydrogen sulfide, which can be produced in the colon through putrefaction of meat and may be associated with inflammatory bowel disease; secondary bile acid, which may increase the risk for certain cancers, and Trimethylamine (TMA), a fishy smelling compound that is a by-product of choline, found in eggs, milk, liver, red meat, poultry, and fish, and may increase the risk of heart disease and stroke.
Conversely, a whole-food, plant-based, high-fiber diet can have beneficial effects on our gut bacteria. Such a diet feeds bacteria that produce butyrate. Butyrate can be absorbed by our colon lining and block inflammation. Lignans from plants are converted to human lignans by our gut flora. High concentrations of lignans are associated with lower breast cancer risks. Sulforaphane, a powerful phytonutrient can also be produced by gut flora.
Image Credit: TLFurrer / Thinkstock. This image has been modified.
Topic summary contributed by Linda
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