Blokes fart on average 14 times per day, expelling 400-2400ml gas/day, and 60% of these are smelly. On the other hand, women fart 50% less and they are less putrid.

So much brave research has occurred into flatus there is now a supposed science of flatology. There has, however, been no such exquisite studies into burping and belching.

The gas that is burped or farted is made up of 5 main chemicals: nitrogen, carbon dioxide, hydrogen oxygen & methane. It mostly comes from swallowed air, and breakdown of food in the gut. We swallow around 300 times per day and each time we suck in 3ml of air. Foods and beverages also contain considerable gas. Digestion of the food in the bowel by acid, enzymes and bacteria all generates more gas. This in turn depends on what food you eat and what bugs that live normally in your bowel. The common foods that tend to cause more gas than others are shown in Table 1.

Methane is one of the main causes of smelly farts. Bugs producing methane are only found in 30% of the population. So if you have smelly ones – it may not be your fault – you can blame it on your bowel germs.

Abnormal burping & farting

First, it is important to say that what appears normal burping and farting to one bloke may be socially unacceptable to another or their friends & family.

Some people even believe they can entertain others with their breaking of wind. There is an infamous Frenchman, Monsieur Joseph Pujol (under the stage name of Le Petomane) who entertained full houses at the Moulin Rouge in the nineteenth century by 'playing' various tunes and requests via the passage of apparently unlimited quantities of flatus. He had trained his anus to suck in air!

So how much is too much farting?

Normally men produce less than 100ml flatus per hour. However, since we don’t tend to measure volume, counting the frequency of gas passage is a more helpful indicator. Passing gas more than 25 times per day is usually considered abnormal.

Dr Bob now answers some frequent questions about abnormal burping and farting:

Dr Bob: The most likely cause is excessive air swallowing, or aerophagia as it is technically called. One of the valves of the upper gullet relaxes and this sucks air into the gullet. Most of the air only passes part of the way down the gullet and then is noisily expelled.

Mr Belcher: But why me?

Dr Bob: Well you may have some risk factors which may make you more prone to aerophagia. These factors include anxiety, nervous habits, heartburn, dyspepsia (upset stomach), drinking too much carbonated drinks or sodium bicarbonate compounds.

Mr Belcher: So what can I do about it?

Dr Bob: A good overhaul of your lifestyle would be a good start. Cutting down your cola intake to 1 glass per day, losing some weight and doing a stress management program would certainly help. If that does not work you could try Degas (simethicone) available from your chemist.

Dr Bob: Firstly it is important to note that it is rarely caused by serious gastro-intestinal disease. The most likely cause is simply excessive fermentation of high fibre foods. Nevertheless there are a number of more serious causes which need to be excluded: lactose (milk sugar) intolerance, malabsorption of fat, disorders of bowel movement, a germ called giardia, and irritable bowel syndrome.

Do you have stools which are bulky & difficult to flush down the toilet, nausea, frequent abdominal pain, or frequent change in your bowel habit?

Mr Tailwind: No.

Dr Bob: Then you probably just make too much gas- nothing serious. The treatment for this mostly revolves around diet modification. Reduce the amount of fibre or change the type of fibre in your diet, especially avoiding beans or any foods which you feel produce gas. Some protein foods, including meat & eggs make farts smell, as do onions, garlic, some herbs and some concentrates such as shrimp paste.

Try and stick to the same foods each week as your bowel bacteria get used to them and ferment less. Also avoid aspartame (the artificial sweetener), and chewing gum (as this reduces the amount of air sucked in). If all that fails you could try charcoal tablets or fennel & raspberry leaf teas.

Mr Tailwind: Is it harmful to hold in wind?

Dr Bob: No. Fart holders tend to be anxious people who are embarrassed about releasing gas. It can become a habit. This can lead to bloating, and sometimes abdominal pain.

Mr Tailwind: That reassuring but I was worried about lactose intolerance because I'm Greek.

Dr Bob: Lactose intolerance is the commonest disease where food is incompletely digested and so passes through to the large bowel where it is fermented. This causes excessive amounts of wind and frequently diarrhea. In this condition there are inadequate amounts of a digestive enzyme lactase, which breaks down milk sugar. This decline in the amount of lactase especially occurs after the age of 5 years. Lactose intolerance is found in 50-90% of some ethnic groups e.g. Greeks, Jews, Africans, Black or Latin Americans & Asians.

Mr Tailwind: Is there any treatment?

Dr Bob: Sure is. You could just avoid dairy products, especially cows milk, as they contain most of the lactose. Soy milk is a healthy alternative. There are tablets which can be added to cows milk to help with the digestion of lactose (e.g. Lact Aid). Lactose reduced dairy products are also available from many health food stores. Natural yogurt with lactobacillus also appears well tolerated.

Bon Appetite!

References: Man Maintenance (1996) Jill Margo Penguin, Sydney

Wind Breaks (1993) Terry Bolin & Rosemary Stanton

If you would like to ask Nick a question about your wind or anything else medical you can do so by visiting his Special Adviser's area by clicking on Special Advisers in the menu bar below.