What causes human gas?

Answer 1

For Flatulence, Probably Primarily, the Action Of Bacterial Formic Dehydrogenase (H2 and CO2) in the Large Intestine.

Answer 2

Gas in the digestive tract (that is, the esophagus, stomach, small intestine, and large intestine) comes from two sources:

1) Swallowed Air
Air swallowing (aerophagia) is a common cause of gas in the stomach. Everyone swallows small amounts of air when eating and drinking. However, eating or drinking rapidly, chewing gum, smoking, or wearing loose dentures can cause some people to take in more air. Burping, or belching, is the way most swallowed air—which contains nitrogen, oxygen, and carbon dioxide—leaves the stomach. The remaining gas moves into the small intestine, where it is partially absorbed. A small amount travels into the large intestine for release through the rectum. (The stomach also releases carbon dioxide when stomach acid and bicarbonate mix, but most of this gas is absorbed into the bloodstream and does not enter the large intestine.)

2) Breakdown of Undigested Foods
The body does not digest and absorb some carbohydrates (the sugar, starches, and fiber found in many foods) in the small intestine because of a shortage or absence of certain enzymes. This undigested food then passes from the small intestine into the large intestine, where normal, harmless bacteria break down the food, producing hydrogen, carbon dioxide, and, in about one-third of all people, methane. Eventually these gases exit through the rectum.
People who make methane do not necessarily pass more gas or have unique symptoms. A person who produces methane will have stools that consistently float in water. Research has not shown why some people produce methane and others do not.
Foods that produce gas in one person may not cause gas in another. Some common bacteria in the large intestine can destroy the hydrogen that other bacteria produce. The balance of the two types of bacteria may explain why some people have more gas than others.

Answer 3

Foods providing nutrients are digested by enzymes and acids in the stomach and small intestine where the nutrients are released then absorbed through the intestinal wall for transport via the blood throughout the body. A food resistant to this process is undigested, as insoluble and soluble fibers.

In the lower intestine they are fermented by gas-producing bacteria which make carbon dioxide, methane, and/or hydrogen -- leading to the flatulence commonly associated with eating beans. Eg.Raffinose is broken down by the intestinal bacteria with the help of the enzyme alpha-galactosidase.
Flatulence (expelled from humans through a processes commonly known as 'farting' or 'emitting gas') is the presence of a mixture of gases known as flatus in the digestive tract of mammals.
Nitrogen is the primary gas released. Methane and hydrogen, lesser components, are flammable, and so flatus is susceptible to catching fire. Not all humans produce flatus that contains methane
The gas released during a flatus event frequently has a foul odor which mainly results from low molecular weight fatty acids such as butyric acid (rancid butter smell) and reduced sulfur compounds such as hydrogen sulfide (rotten egg smell) and carbonyl sulfide that are the result of protein breakdown.

Answer 4

Bacteria decompose food particles creating intestinal gasses such as methane and nitrogen. This is however not true for burping, that is just trapped CO2 (sodas) or air.

Answer 5

Mostly swallowed during eating, some by bacterial action. The former is the greatest amount.

Answer 6

I don't know the answer, but I've always heard that anything that eats farts. I'm sure it has something to do with the digestion process.