Brief Answer:
Overall indigestion with disturbed microbiota.
Detailed Answer:
Hello,
Thanks for choosing HealthcareMagic or your query Dear.
I am a Gastroenterologist and would be answering your query.
Have gone through your query and i appreciate your concerns.

Answer to your question is-

Gas collects in our gut in two main ways-

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 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.


Suggestion-
Proper food habits are very essential to control excessive flatulence.
Avoid-
Dairy products, which contain sugar lactose that causes gas.
Vegetables, including onions, radishes, cabbage, celery, carrots, brussel sprouts, broccoli, cauliflower and legumes.
Fruit sugar, which is especially high in prunes, raisins, bananas, apples, apricots and fruit juices from prunes, grapes and apples
Fiber.
Fatty foods and carbonated drinks.

Eating more fermented foods. These are rich in both good bacteria and enzymes you can try raw natto kefir or cultured veggies. This is probably one of the most important first steps.
Taking a high-quality probiotic.
Exercising, to help keep food moving through your system.
Using spices that may help to prevent flatulence. These include turmeric, coriander, peppermint, fennel, sage, chamomile and ginger.
Finally, when you reintroduce a food that was previously a gas-causing food, be sure you do so slowly. This will give your body a chance to adapt to the adjustment.

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


Hope i answered your query with relevent details.I have included pathophysiological details also so that you can understand things better as you have asked the same question twice before, therefore i have tried to include all details you could be looking for.

In case you need any other professional advice feel free to ask.
Thank you.

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