Whether you’re trying to control your stench or make money off of it, keep reading! In this article, we answer the question, “Why do my farts smell so bad?” plus tips for reducing or changing their fragrance.

The Science Behind Why Farts Smell So Bad

Let’s start with the scientific side of things. As bacteria in your digestive system break down the foods you eat, hydrogen sulfide is produced. When this gas mixes with other natural gasses in the body, it produces a smell close to the unpleasant odor of rotten eggs – also described as sulfur.

These gasses build up inside the digestive tract and, eventually, are released as farts. Most people fart between 13 and 21 times per day. While some farts may be odorless or have a mild smell, others are much stronger and more offensive (or attractive, depending on who you ask). Farts smell differently for many different reasons.

For example, if too many bacteria break down too quickly, undigested food can remain in your large intestine, creating more fragrant farts. Excessively smelly farts may also be a sign of an underlying health condition, which we’ll cover below.

The 7 Most Common Reasons Why Farts Smell So Bad

No two bodies function the same, but here are some of the most common causes of offensively odorous gas.

Food Intolerance

According to one study, as many as 20% of adults have some type of food intolerance. Some of the most common intolerances include dairy, gluten (more on this below), caffeine, amines, fructose, and sulfites. A food intolerance describes digestive issues that occur after eating certain foods. These food sensitivities can result in a long list of symptoms, including:

• Diarrhea
• Nausea
• Bloating
• Abdominal pain
• Acid reflux
• Increased flatulence

Non-gastro-related symptoms and side effects may include a skin rash, headaches, fatigue, or a runny nose.

When it comes to the smell of your farts, food sensitivities can cause your body to react in unpleasant ways, like producing extra smelly gas. For example, people who are lactose intolerant or sensitive to dairy struggle to break down sugar in products like milk, cheese, and ice cream. This trapped sugar is then fermented by gut bacteria, causing a build-up of foul-smelling gas.

Bacteria Build-Up

Speaking of bacteria build-up, this is another common cause for offensive odors and doesn’t always result from food sensitivity. The large intestine is filled with good and bad bacteria, known as the gut microbiome. Healthy bacteria work to break down the foods and carbs you eat, extracting beneficial nutrients and sending them into your bloodstream. The waste is then sent to your colon. When this digestive process is interrupted, it can cause an overgrowth of bad bacteria, known as dysbiosis. This build-up of bacteria can cause digestive issues, discomfort, and super-smelly tots.

During the natural digestive process, your gut bacteria also produce hydrogen sulfide and other compounds that also contain sulfur. As mentioned above, the smell of sulfur is often described as rotten eggs. The number and type of bacteria present in your gut will impact not just how often you pass gas but how offensive your farts are. Some people are also cursed (or blessed, depending on how you view it) with a certain flora that consistently produces smellier farts.

Constipation

Consistency when it comes to bowel movements varies significantly from person to person. The recommended number of bowel movements can range from as many as three per day to as few as three per week! Constipation is characterized by less than three bowel movements per week or difficulty trying to go. Other symptoms of constipation include:

• Hard stool
• Stool that looks like rocks or pebbles
• Unusually large or small stools
• Straining or experiencing pain when trying to go
• A “blocked” feeling even after you’ve had a bowel movement

Inconsistent bowel movements can also trigger more gas – in both volume and stench. When you’re constipated, it takes longer for stool to pass through your colon and out of your body, giving feces (and its fragrance) more time to build up in your intestines. According to one doctor, if the stool hangs around for too long, “bacteria can really go to town and cause lots of gas.”

Eating Too Many High-Fiber Foods

Getting enough fiber in your diet is important for several reasons. For starters, it helps keep you regular. Studies show that people who consume between 25 and 30 grams of fiber per day have more frequent and more regular bowel movements. Fibre also helps balance your microbiome, lowers blood pressure, keeps you feeling fuller for longer, and helps balance cholesterol levels.

Unfortunately, some side effects of a high-fiber diet aren’t as pleasant or positive. Eating too much fiber can increase gas and gas symptoms like bloating, cramping, and, yes, stinky farts too. Fiber is found in countless foods, but the most popular include fruits, whole grains, and most vegetables. It should come as no surprise that strong-smelling vegetables like broccoli, cabbage, and bok choy produce some of the stinkiest gas.

As beneficial as these foods are, they’re also difficult to digest and break down. If you’re consuming too much fiber in an effort to promote healthy bowels, you could be overdoing it. To avoid a spike in gas and discomfort, try increasing your fiber intake slowly over time.

Certain Medications

Since you have control over your diet, you can regulate the smell of your farts to some degree. Unfortunately, if you have a medical condition that requires certain medication, you may not have a choice but to take that prescribed amount. And those medications may be the underlying cause of your foul-smelling flatulence.

Certain medicines can not only impact how your farts smell but also how many you produce. These include both prescription and non-prescription. Here are just a few of the most common.

• Antacids
• Iron pills
• Multivitamins
• Opioid pain medicine
• Diarrhea medication
• Fiber supplements
• Bulking agents
• Antibiotics
• Statins

If you’re wondering, “Why do my farts smell so bad?” and you’re currently taking any of these medications, they could be the culprit. Speak to a doctor before stopping their use or considering an alternative drug.

Consuming FODMAP Foods

New research has uncovered a link between FODMAP foods and farts. FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. In simple terms, these are short-chain carbohydrates and sugars that the small intestine struggles to absorb. This difficulty can trigger gastrointestinal discomfort, including bloating, cramping, diarrhea, constipation, and increased flatulence. FODMAPs also include starches and fibers, as well as the following food items:

• Fructose (fruits like grapes, peaches, and bananas), high-fructose corn syrup, and honey
• Fructans (garlic, wheat, and onions)
• Galatians (legumes and beans)
• Lactose (dairy products like cheese, yogurt, and milk)
• Polyols (pitting fruits including cherries, avocados, and apples)

Once consumed, the carbs from these foods collect water to help them move smoothly through your digestive system. Your microbiome quickly breaks down these carbs, creating an increase in gas in the process. People with IBS (irritable bowel syndrome) are more likely to experience the unpleasant side effects of eating too many FODMAPs, including diarrhea, bloating, and smelly farts.

Diseases or Infections

Fragrant farts may not just be unpleasant for you and those around you. They could also be your body’s way of signaling that something is wrong. Foul-smelling farts could be a sign or symptom of certain undiagnosed conditions, including:

Bowel Obstruction

Obstructions that block your digestive tract may include tumors caused by different cancers like ovarian and colon.

GI Disorders (Functional Gastrointestinal Disorders)

GI disorders include health conditions that link your brain and body (gut). The most common GI disorder that could cause foul-smelling farts is IBS (irritable bowel syndrome).

GERD (Gastroesophageal Reflux Disease)

Often referred to as heartburn, GERD occurs when the contents of your stomach travel up toward your esophagus. Not only is this condition extremely uncomfortable, but it can cause more unpleasant symptoms like bad breath, thinning tooth enamel, and especially odorous gas.

Gastroparesis

This rare condition stops or slows food from properly moving through the digestive tract. Trapped food means more trapped gas and bacteria, resulting in more fragrant flatulence.

SIBO (Small Intestine Bacterial Overgrowth)

SIBO changes and often increases the amount of bacteria present in the gut, which can cause excess gas and offensive-smelling toots.

Intestinal Psuedo-Obstruction

This is a rare condition that causes a bowel obstruction without a physical blockage present. Most times, this blockage is caused by muscle or nerve damage.

It’s important to note that most of these infections are also accompanied by other symptoms, so avoid self-diagnosing and check with a medical professional for further evaluation. Additional symptoms may include abdominal pain, constant pressure even after emptying your bowels, nausea, vomiting, and fatigue.

Celiac Disease

Although celiac disease could be classified as both a food intolerance and an underlying health condition, it deserves its own spot on this list. One reason is that over 2 million people in the United States alone suffer from this disease, which is another way of describing gluten sensitivity.

Gluten, a protein found in grains like wheat, rye, and barley, is often associated with painful and foul-smelling gas. Most people with celiac disease only experience these side effects after consuming gluten. Once you diagnose it, you can avoid these foods and adopt a gluten-free diet. For those unsure of whether or not they have celiac disease, signs include fatigue, headaches, and even mood swings. The fastest way to diagnose this condition is a routine blood test performed by your doctor.

Some of the most commonly consumed foods containing gluten are:

• Whole grains
• Baked goods (breads, cakes, biscuits, pies, and pastries
• Pasta and noodles
• Energy bars
• Potato chips
• Candy
• Lunch meat
• French fries
• Granola bars
• Salad dressings
• Sauces
• Seasonings

If your diet contains any of these foods and you’ve noticed the smell of your farts getting worse, celiac disease might be the cause.

Tips for Improving the Smell of Your Farts

While some people are turned off by the overwhelming smell of backdoor odor, other people actually enjoy it. People who like to smell farts, incorporate farts into their sex practices, or be treated as a fart slave, are defined as fart fetishists.

This growing fascination with farts is another reason why selling farts in a jar is also becoming increasingly popular. If you want to improve the smell of your toots so you can bottle and sell them, check out these tips!

• Eat smaller meals more often (this encourages healthy digestion and reduces gas production)
• Hydrate (drinking water helps the digestive tract run smoothly and more efficiently)
• Incorporate probiotic foods into your diet to help restore the balance of healthy bacteria in your microbiome
• Avoid carbonated beverages that produce excess gas, like soda, beer, and sparkling wine
• Avoid foods associated with super-smelly farts, including broccoli, brussel sprouts, cauliflower, kale, eggs, meat, fish, poultry, onions, garlic, and scallions
• Try over-the-counter gas medicines to help breakdown complex carbs and reduce the frequency and intensity of your farts

FAQs About Smelly Farts

The more you know about how and why your body produces especially foul-smelling farts, the better you can control them. Whether you want to produce more for selling farts in a jar or fewer to avoid embarrassment, here are some frequently asked questions on the topic.

How often should I be farting?

The average healthy adult farts between 12 and 25 times per day. Most farts are produced while you sleep since the amount of gas in your intestinal tract increases as the day goes on. If you want to capture farts in a jar, you may need to put in some long hours to capture those precious nighttime toots. Swallowing air may also increase the frequency of your farts. 

Should I see a doctor for my smelly farts?

Most fragrant farts are harmless. Although they may cause monetary discomfort or embarrassment, they’re hardly cause for concern. However, if you’re concerned that your toots are especially offensive or your smelly farts are accompanied by other, more unsettling symptoms, it may be time to see a doctor. Additional symptoms include vomiting, severe abdominal pain, unexplained weight loss, bloody stool, and fever.

Why do some farts smell worse than others?

Did you know that only 1% of the gas you expel as a fart actually smells? It’s not the gas itself that has an odor. It’s the intestinal bacteria containing sulfur that creates the unpleasant fragrance we’ve come to know and love. The intensity of the smell is usually associated with the foods you eat, how efficiently your digestive tract breaks it down, and the health of your microbiome.

Now that you know more about why your farts smell so bad, you can take the next steps to either capitalize on your fragrant flatulence or eliminate it. Whichever you choose, just don’t hold in your farts! Click here to learn why.