Flatulence 101: The Fundamentals Behind Why Human Farts

August 10, 2022
Flatulence 101: The Fundamentals Behind Why Human Farts

We are all familiar with flatulence, or as most would commonly call it, farting. When it happens, most will take it either way: funny, embarrassing, or offensive. It can happen with a thunderous arrival or a long and comedic tune. It sometimes even goes unnoticed – silent and deadly.

But how does flatulence occur?

Flatulence is a normal bodily process that occurs when bacteria found in the large intestine break down things in our diet that our body does not break down. In the process, gas is produced as a by-product. If our body does not release the gas, we will naturally explode.

The human body releases gas in two ways: flatulence and burping. Flatulence happens in the lower gastrointestinal tract, while burping occurs in the upper gastrointestinal tract when we swallow air.

Why does flatulence stink?

Most of the time, flatulence does not smell bad because it contains odourless gases, including oxygen, hydrogen, nitrogen, carbon dioxide, and methane. However, the times that it stinks, the gas released may have a small amount of hydrogen sulphide, which contributes to the rotten egg smell. Other factors of stinky farts might be the by-products produced when the gut bacteria in the colon break down meat and if faeces are present in the rectum when you fart.

What drinks and foods contribute to flatulence?

Often when patients visit doctors for excessive flatulence, the first thing many doctors will check is their diet history. Some foods are highly associated with contributing to flatulence, such as:

  • Sugars, such as table sugar (glucose), milk sugar (lactose), and fruit sugar (fructose)
  • Beans, such as kidney beans, pinto beans, and black beans
  • Beverages, such as milk and apple juice
  • Dairy products, such as ice cream and cheese, as well as recipes that consist of added lactose
  • Vegetables, such as broccoli, brussels sprouts, onions, asparagus, cabbage, cucumbers, and carrots
  • Whole grains, such as whole wheat and bran

Foods associated with contributing to stinky flatulence include beans, coffee, eggs, prunes, asparagus, cabbage, dairy products, and onions.

When should flatulence warrant a doctor’s visit?

When it becomes excessive to the point you feel uncomfortable. As long as you have noticed specific changes in the intensity and frequency of flatulence, and especially when you start to experience abdominal pain, it is highly recommended then to visit your family doctor or a gastroenterologist.

What kind of medical conditions result in excessive gas?

Medical conditions that result in excessive flatulence happen through several mechanisms. Celiac disease and lactose intolerance result in bloating and flatulence because the body has difficulty breaking down certain carb elements. Other conditions, such as dumping syndrome, abdominal hernia, and abdominal adhesions, result in the stomach functioning abnormally, with excessive gas being one of the critical symptoms. Additionally, certain medications, such as antacids and ibuprofen, may lead to an increase in the production of gas.

Fun Flatulence Facts

  • A human may fart up to 21 times a day
  • Farts are flammable because they contain methane and hydrogen


Flatulence is a normal process that can be maintained with the proper lifestyle and diet habits. Nevertheless, if you struggle with excessive flatulence, it might be best to make a doctor’s appointment or visit any of our gastroenterologists at GUTCARE. If your flatulence is found to be related to a specific health condition, then treating it as soon as possible will make you comfortable and healthy. Besides the usual gut conditions, we also offer haemorrhoid treatment. Visit https://www.gutcare.com.sg/ to make an appointment today!