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Detailed Answer:
Hi sir as you digest food, digestive gases are formed as a result of fermentation and digestion of food which can also collect. Either method can cause flatulence.

The pathophysiology of gas and flatulence is complicated.
The term gut microflora or microbiota means hundeds of species of bacteria which lives in our intestinal tractintestinal tract.These bacterias and yeast are responsible for proper digestion and fermentation of food. Hundereds of species of bacteria and yeast re found in colon of human intestine.In the same way thousands of these species florishes in our gut these bacteria play a vital role in digestuio and absorption of food.Even minor disturbances in gut microflora can lead to significant changes in gut function, including gas production.
There are various mechanism that can be related to increased flatulence
If this microbiota is disturbed food is improperly fermented causing production of large amount of gases in gut leading to severe flatulence.Hence most commmon cause in most of the cases is disturbed microbiota.In old patient mobility of intestines is severly compromised leading to accumulation of large amount of gases in intestines.As persitaltic moments are week gas accumulates in intestines.Severe constipation or incomplete evacuation can also hinder the passage of gases.
Small Intestinal Bacterial Overgrowth can be a reason of severe flatulence .
Small intestinal bacterial overgrowth (SIBO) refers to a condition in which abnormally large numbers of bacteria are present in the small intestine, and the types of bacteria in the small intestine resemble more the bacteria of the colon than the small intestines causing improper and disturbed food digestion.


Tests suggested-
Small bowel imaging and a gastric-emptying scan.


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Thanks!

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