Brief Answer:
Details follows

Detailed Answer:
Hi,

Swallowing air while you eat or drink can cause air to collect in the digestive tract.

Second, 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. Understanding gut microflora, gas production, intestinal transit, intestinal propulsion of gas, and sensory function within the GI tract are essential for understanding symptom generation.

The term gut microflora or microbiota means hundreds of species of bacteria which live in our intestinal tract.These bacterias and yeast are responsible for proper digestion and fermentation of food. In the same way, thousands of these species flourish in our gut and play a vital role in digestion and absorption of food. Even minor disturbances in gut microflora can lead to significant changes in gut function, including gas production.

There are various mechanisms that can be related to increased flatulence

If this microbiota is disturbed food is improperly fermented causing the production of a lot of gases in the gut leading to severe flatulence. Hence most common cause in most of the cases is disturbed microbiota. In elderly, the mobility of intestines tends to compromise leading to accumulation of a lot of gases in intestines. As peristaltic moments are weak 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.

Hope I answered your query.
In case you need any other professional advice feel free to ask.
Thank you.

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