The gut, including the gastrointestinal tract and digestive system, is the primary location for microbiota in individuals. Usually, there is a symbiotic relationship between gut microbiota, or gut flora, and humans. In healthy individuals, the composition of the microbiota in the gut has crucial roles in the digestion of foods, metabolism, and even in regulating moods of the individual. For individuals with unhealthy diets, whose natural gut microbiota has been impaired or disrupted by pathogenic microbiota, an imbalance can occur resulting in disease including diabetes conditions, mood disorders, and autoimmune disease.
Some gut microorganisms have a beneficial effect in the gut of a person because they can ferment dietary fiber which can then more easily be absorbed. Bacteria of the intestine produce vitamin B and vitamin K, and also have critical roles in metabolism. In this way, the gut microbiota acts like an endocrine organ which is a critical part of the biological system called gut microbiota-brain-fat-axis. Disruption of this axis has been associated with type 2 diabetes, eating disorders, and intestinal inflammation.
To help support natural healthy gut flora, individuals can consume prebiotics and probiotics. Prebiotics promote growth and activity of beneficial microorganisms, whereas probiotics are actual living microorganisms that can potentially restore or improve gut flora. For example, live probiotic cultures are present in fermented dairy products and probiotic fortified foods including pickled vegetables, soy sauce, and yogurt. Probiotics are also available as supplement pills for those who are not consuming sufficient amounts in their diet.
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