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Farting, Gas and Flatulence
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Farting, Gas and Flatulence

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Farting, Gas and Flatulence
Dietary fibre, flatulence, farting and gas.

Why do Faeces smell?

Why do we fart?

What is Flatulence?

Do older people produce more gas than younger people?

Does swallowing too much air cause flatulence?

Is the gas produced in the Colon harmful?

What is Bloating?

What causes Bloating?

What is intestinal gas? What are the symptoms of intestinal gas—Flatulence, Belching, Abdominal bloating and distention, stomach pain

Farting and Gas

What causes gas?—intestinal Bacteria, types of gas, types of bacteria

What foods cause production of excess gas or farting?

Is it better to avoid these foods or can we eradicate the gas producing bacteria?

Is it normal to produce excess gas in the upper intestines?

Some facts about flatulence

Intestinal gas is often termed Flatus.

We produce between half and one and a half litre of flatus every 24 hours.

There are no reported differences between the total volume of gas emissions by men and women, although men appear to emit more often than women.

How much gas and how often an individual will produce flatus depend on the fibre content of the diet and the population of the microflora of the colon.

Large volumes of gas production follow meal times.

Less gas is produced during sleeping hours.

The more fibre you consume, the more gas is produced.

Vegetables such as onions, legumes including dried beans and peas, Cauliflower, Brussels sprouts, cabbage and broccoli contain polysaccharides called Fructooligosaccharide and Inulin (soluble fibre) which is selectively fermented by the gut microflora, resulting in copious amounts of gas.

Milk contains the sugar called Lactose. Some individuals lack the enzyme Lactase for digestion of this milk sugar and so it ends up as food for the Bacteria in the intestines. Fermentation of Lactose leads to the production of a lot of gas which may cause abdominal distension and pain.

Confectionery labelled as reduced sugar or low calorie and often directed towards diabetics contains alternative sweeteners such as Sorbitol, Mannitol and Xylitol. These sugars may be fermented by the commensal bacteria in the intestines and can be problematic to those individuals who may be intolerant to these alternatives.

Foods high in fibre and resistant starch lead to flatus. Even though these foods are essential for good health and prevention of disorders related to the lack of fibre in the diet, some people are unwilling to consume these due to the embarrassment and distress of flatus.

Flatus should be regarded as a positive signal that all is well within the colon. It indicates that fermentation is taking place within the colon, leading to the formation of the perfectly formed stool and beneficial short chain fatty acids which may contribute to an enhanced immune system.

Types of gas produced
Odourless gases are Carbon dioxide, Oxygen, Nitrogen, Hydrogen and Methane.

Foul smelling gases produced on occasion are Skatole, Indole and Hydrogen sulphide.

The characteristic smelly odour is due to production of trace gases such as skatole, indole, and sulphur-containing compounds such as hydrogen sulphide and Methanethiol.

About one third of the total gas content of flatus is Nitrogen and originates from swallowed air. Most of the Nitrogen swallowed with air is reabsorbed in the Stomach and small intestine.

Oxygen in flatus is also from swallowed air and most is reabsorbed in the Stomach and duodenum. Not much oxygen is present in the small intestine and colon and results in anaerobic conditions, which favour the growth of anaerobic bacteria.

Carbon dioxide gas is produced during the process of digestion when Hydrochloric acid present in gastric juice reacts with food content such as fatty acids and bicarbonate, which is secreted in the duodenum and small intestine to neutralize acid in content arriving here from the Stomach.

Hydrogen gas is a product of bacterial fermentation in the colon and is produced in the presence of soluble fibre, resistant starch and sugars such as Lactose and Sorbitol that may have escaped complete digestion. Some Hydrogen gas is reabsorbed from the colon and expired from the lungs.

Methane is produced by bacteria present in the left colon from Hydrogen and Carbon dioxide that is produced by other species of bacteria.
Not all individuals harbour these Methane producing Bacteria and those that do suffer less flatulence since the volume of Hydrogen and Carbon dioxide has been reduced in the process.

Hydrogen Sulphide
is produced by fermentation of foods containing sulphate by Bacteria known as Sulphur reducing Bacteria. This gas is the major contributor to the foul smell of flatus.  Not all individuals harbour theses Sulphur reducing bacteria and it appears that one is either a Methane producer or Hydrogen sulphide gas producer.

The digestive process involves breakdown of food into its constituents so that absorption can take place. This process is facilitated by digestive enzymes. This process itself can lead to the production of certain gases. However, the bulk of the gas produced by the human digestive system can be attributed to:
1. Air swallowed during the Eating process and while talking.
2.Gases produced by the resident Bacteria and sometimes Yeast in the intestines and occasionally in the stomach by a process of fermentation of ingredients in ingested food that arrives into the Cecum in the undigested waste from the small intestine.
These are mainly sugars and polysaccharides but often proteins.

Swallowed air is usually expelled in the form of a burp at the end of the digestive process in the stomach.

Fermentation of food substances by yeast and bacteria can occur in the upper small intestine occasionally due to this segment of the digestive system being infected by pathogenic or disease causing bacteria and yeasts that are not normally present in high concentrations. The production of gas in these circumstances causes a feeling of BLOATING and may cause repeated BELCHING.
Fermentation of polysaccharides in the Cecum and Colon is normal due to the presence of resident bacteria in this segment of the digestive system. The type of gas produced depends on the presence of
1. Particular types of food sources for the bacteria to feed upon or ferment
2. The type of bacteria present and their ability to ferment particular food ingredients present

the presence of Bacteria known as “Sulphur Reducing Bacteria” in the colon can lead to the production of certain TOXIC gases. These gases can lead to tissue death and inflammation if allowed to accumulate and linger.
These bacteria can feed on food ingredients that contain sulphur to produce the gas Hydrogen Sulphide and Methane.
Hydrogen Sulphide is a particularly toxic and smelly gas. Sulphur containing foods are usually proteins and eating animal protein often leads to the production of large quantities of this gas.
Hydrogen Sulphide is also produced when one consumes certain plant foods that contain Sulphur. Cruciferous plants such as Cabbage, Broccoli, Cauliflower and Brussels sprouts, Garlic and Leeks may cause the production of hydrogen sulphide by the action of these sulphur reducing bacteria in susceptible individuals.

Epsom salts, which is Magnesium Sulphate, is often used as an osmotic laxative and people who harbour sulphur reducing bacteria in the colon will note that when they fart they produce a gas that has the characteristic smell of rotten eggs. This is Hydrogen Sulphide and is produced by the action of these bacteria on the Sulphate portion of the Epsom salt.

The Sulphur reducing Bacteria are also able to ferment other non food material that may be present in the colon. Fermentation of Pancreatic enzymes left over from the process of digestion in the small intestine, mucus and sloughed epithelial cells in the faecal mass will lead to the production of Hydrogen Sulphide gas.
The amount of Hydrogen sulphide gas produced depends on:

1.The amount of sulphur containing material available for fermentation.

2.The population of Sulphur reducing bacterial species present in the colon.

3.The intestinal transit time, which is determined by intestinal motility, which in turn depends on how healthy the smooth muscles of the intestine are.

4. The ph or acidity of the colon contents.


The reducing bacteria that make Methane do not grow in an acid environment.

Likewise, those that make the smelly hydrogen sulphide in the colon do not grow in an acid environment.

If your flatus has none or little smell, your colon may be at the right acidity to prevent the Hydrogen Sulphide producing bacteria from growing.

The ph can be manipulated towards acid by consuming foods that contain resistant starch, Fructo-oligosaccharides and Inulin.
These substances are converted by the resident “friendly Bacteria” in the colon into Lactic acid and other SHORT CHAIN FATTY acids that make the colonic contents acidic and discourage multiplication of the Sulphur reducing bacteria.

Another option to reduce production of the toxic and foul smelling Hydrogen Sulphide gas in the large intestine is to limit consumption of Sulphur containing protein foods.


How to heal and prevent Bowel disorders

Diet is not about what you should NOT eat, it’s about what you should include in the diet that matters.
As long as your diet includes the correct balance of plant foods containing soluble fibre, insoluble fibre and resistant starch your colon will produce the perfectly formed stool. The important next step is to evacuate this stool without straining so that the body does not suffer from the pressures created each time the bowel is emptied.

In order to heal and prevent bowel disorders you need to make lifestyle changes that last the rest of your life time.

1. Include more fluids and plant food containing soluble fibre, insoluble fibre and resistant starch in the diet so that the perfectly formed stool will be made in the colon and beneficial bacteria will flourish and eliminate disease causing bacteria and fungi.

2. Evacuate the perfectly formed stool by adopting the squat posture to eliminate the need to strain during bowel movements.

It is not possible or safe to squat on the modern raised toilet seat installed in all western homes and it is impossible to squat for any length of time if you have not done this from childhood onwards. This makes the use of any raised platforms impossible to adapt to.

The SquattLooStool is designed to allow you to adopt the squat posture while seated comfortably on your raised toilet seat.
The single best and easiest lifestyle change you will ever make, leading to a healthier body.