Yes, it’s a pretty taboo subject and not one you’re probably going to discuss with friends, but actually your farts can tell you a lot about your gut health AKA flatulence fortune tellers. Here, we attempt to explain what your fart really says about you.
Content Outline
- The Truth About Gas
- Why Do You Fart?
- Which Type of Farter Are You?
- Top Gas-Producing Foods
- Summary: Are Smelly Farts a Bad Thing?
The Truth About Gas
Passing gas may be embarrassing, but it’s just a normal fact of life. We all do it, don’t let anyone tell you otherwise. Most people fart between 10 and 20 times a day, but up to 25 times, whether they realise (or admit) it or not. But have you ever wondered why you fart? What is the point in flatulence, and what can it tell you about your gut?
Farting isn’t just a thing we do, it’s a powerful indicator of your gut health. From the smell to the frequency, the gases your body produces can give you insightful clues about the behaviour of your gut bacteria and whether your digestive system is thriving, just surviving, or struggling.
Here, we explore what your farts can really tell you about your gut health. So, if you’ve got over the initial horror of this article, let’s bake break break wind.
Why Do You Fart?
Passing wind, blowing off, farting, whatever you call it is a natural byproduct of digestion, particularly related to the work of your gut bacteria. When food reaches the colon, your gut microbes break down leftover carbohydrates, especially prebiotic and fermentable fibres, producing gas. Some of the gases are reabsorbed, some are exhaled, and the rest escapes via your anus.
The fermentation process that occurs in your gut produces gases like:
- hydrogen
- methane
- carbon dioxide
- hydrogen sulphide1
Excess gases leave the body as flatulence, with gas itself referred to as flatus. The type and amount of gas you pass depends on several factors, including the composition of your gut microbiome, diet, and how well your digestive system is working.
How Much Farting is Too Much?
According to research, the average healthy man passes wind 14 times per day but up to 25 times a day is considered normal2. Farting every day is normal, but you may notice you do it more when you eat certain foods and it’s a sign that your digestive system is working properly.
However, if you’re very gassy and are farting more than 25 times a day, it may be a sign of an unhealthy gut. Frequent flatulence may be a sign of a food intolerance, such as lactose intolerance, or other digestive issues.
Which Type of Farter Are You?
While passing gas is normal, sudden changes in your fart patterns, like smell, intensity, or frequency, can indicate shifts within your gut. For example, a sudden increase in gas production could be related to a recent diet change or smelly atmospheric contributions could suggest a high level of protein fermentation. Let’s explore some of the common fart types in more detail.
Sudden Increase in Gas
If you’ve recently upped your fiber intake or maybe added a prebiotic supplement, like the PureHMO® Prebiotic Powder, then an increase in gas is expected. It’s a sign that your gut bacteria are being nourished and are thriving. This usually settles down after a few weeks, but if it’s persistent it may suggest food intolerances, like lactose, gluten, or fructose, or poor absorption.
Excessively Smelly
Odorous farts are caused by sulfur-containing compounds produced by gut bacteria during the digestive process. The major gases in flatulence come from two main sources, swallowed air and bacterial fermentation. They are:
|
Exogenous (swallowed air) |
Endogenous (bacterial fermentation) |
|
oxygen nitrogen carbon dioxide |
hydrogen methane sulfur-containing gases3 |
Gases produced by your colonic bacteria make up 74% of farts4, but less than 1% of gas is odorous – your sense of smell is so good that it can detect even the smallest amounts. Smelly ones are largely a result of sulfur-containing compounds being released by your gut microbes during digestion. Unusually foul-smelling farts can indicate dysbiosis or an imbalanced gut microbiome.
Silent But Often?
Silent but frequent farting can be a sign of conditions such as slow transit colon which can lead to increased gas retention5. Because waste moves too slowly through the colon, it can lead to gas build-up and more frequent and uncomfortable flatulence as your gut microbes break down undigested food.
Small intestinal bacterial overgrowth (SIBO) can increase gas production and flatulence because bacteria in the small intestine ferment undigested food, releasing gases like hydrogen and methane. The type of gas produced in SIBO will determine whether your farts are smelly, but SIBO sufferers are classically windy.
Floating Farter
Floating farts indicate the presence of methane-producers in your gut. Methane is present in 30% to 50% of the healthy adult population6, but it is also linked to constipation-related diseases such as IBS-C and chronic constipation. Methane production is linked to a high abundance of bacteria, such as Methanobrevibacter smithii7, and is known to slow down gut transit time, contributing to bloating and sluggish stools.
Top Gas-Producing Foods
There’s a link between what you eat, how much gas your gut creates, and how it smells. That’s because each food impacts your body and your intestinal ecosystem differently.
Some of the top gas producers include:
These foods are likely to cause more gas because they are rich in fermentable fibers or sugars that are difficult to digest. That’s not a bad thing. In most cases, the gas is a sign that your microbes are being fed.
The smelliest gas your gut microbes make is hydrogen sulfide, but this can only be produced if you eat foods containing sulfur. It’s mainly found in high amounts in animal proteins like red meat and eggs rather than plant proteins.
Proteins are more likely to cause foul odors because they contribute to putrefaction, a process where excess proteins are fermented in the large intestine. Consuming too much protein can cause stinky farts, but is also associated with negative health consequences, like ulcerative colitis and colorectal cancer8.
Fibrous foods like lentils and beans can also make you rather gassy, but that’s because your body relies on the gut microbial community to break them down for us. Thankfully, though, most fiber-rich foods produce non-smelly hydrogen and carbon dioxide.
How to Manage Gas Without Compromising Your Gut Health
If you are experiencing a lot of gas, you don’t (and shouldn’t) eliminate all fiber or prebiotics from your diet. Instead:
- Introduce prebiotics and increased fiber to your diet slowly and in smaller amounts
- Cook your vegetables to make them easier to ferment for your gut bacteria
- Chew your food thoroughly, eat with your mouth closed, and slowly
- Stay active to support your digestive system and encourage food to travel through the GI tract
- Consider a low FODMAP diet if wind is excessive and painful
- Try a prebiotic like PureHMO® IBS Support to create a positive atmosphere for your good gut bacteria
Summary: Are Smelly Farts a Bad Thing?
Not always, but it’s important to know what’s normal for you. Although farting may not be the most pleasant topic, it can tell you a lot about the state of your gut. Whether yours are smelly, silent, or suddenly out of control, your farts are a reflection of the digestive processes occurring inside your body. So next time you pass gas, stop and think about what your body might actually be trying to tell you. Curious about what’s happening inside your gut? Explore our range of science-backed, microbiome-friendly supplements – powered by human milk oligosaccharides (HMOs), designed to support a thriving gut.
Written by: Leanne Edermaniger, M.Sc. Leanne is a professional science writer who specializes in human health and enjoys writing about all things related to the gut microbiome.
