Most dudes fart up to 25 times per day (most of which sneak out while you sleep). It’s understandable that fumes leaking out of your butthole wouldn’t smell pleasant. But sometimes you rip a fart that smells so bad you want to fumigate your house. 

This leads to a common question: Are your farts’ stank levels a matter of random luck, or do you have more control over the smell than you think?

The science behind flatulence is pretty simple: it comes from a combination of gut bacteria and swallowing air throughout the day. The gas in your gut is composed of oxygen, nitrogen, carbon dioxide, hydrogen, and methane (a byproduct of the digestive process, fueled by probiotics).

Most people produce up to 1.8 liters of gas every day (yes, even your IG crush). You might be surprised to know that less than 1% of intestinal gas actually smells bad. So, what makes some farts smell so much worse than others?

Read on to learn seven potential causes of smelly gas—and how to get your stank under control.

Why Do My Farts Smell So Bad?

It’s normal for farts to smell bad. But if you’re passing gas that smells worse than usual, the most likely culprit is your diet—specifically foods high in fiber or sulfur. Foul-smelling farts can also indicate digestive health conditions or food intolerances, but that’s less common. 

We’re going to assume you don’t have time to run experiments to figure out what’s causing your stinky farts, so we broke down six common causes for you.

1. You Have a High-Fiber Diet

High-fiber foods take longer to break down, so they smell worse as they mingle with the enzymes in your digestive system.

Remember the time you scarfed down that bean burrito for lunch then ripped farts smelly enough to clear the whole office? Yeah, that’s because beans are packed with dietary fiber and raffinose that cause gas. Together, they make a deadly combination that’s like rocket fuel for your farts.

Cruciferous vegetables (AKA leafy greens) are also fiber-rich foods. Those helpings of broccoli, Brussels sprouts, cauliflower, and kale are great additions to your diet. But be warned: you might have to wear a gas mask if you inhale those veggie farts after a few hours.

2. You Ate Sulfur-Rich Foods

Sulfur, the third most abundant mineral in your body, is essential for your body to function properly. It also makes your farts smell like rotten eggs. 

Foods high in sulfur include meat, fish, dairy, onions, and garlic. Eating a sulfur-rich diet is healthy in most cases, but it’s a fast path to Stinkville.

3. You Ate a Ton of Protein

If you’re a gym rat who rinses down slabs of meat with post-workout shakes, you already know about deadly protein farts. Normal amounts of protein (about one gram per pound of body weight per day), typically break down in your small intestine into amino acids.

However, excess protein scoots right down to your colon where gut microbes go to town on it. When that happens, your body produces hydrogen sulfide gas, causing your farts to reek like rotten eggs.

4. You Drank Alcohol

As if a hangover wasn’t bad enough, drinking alcohol can cause your farts to carry an odor more shameful than anything you did the night before. The excess yeast and carbohydrates found in beer can go undigested in your colon where they ferment into atomic beer farts.

And if you thought a fancy glass of wine could spare you from stinky gas, think again. Wine contains sulfur, which ends up smelling just as bad as beer farts once it finds its way out of your ass.

5. You’re Constipated

If it’s been a while since you’ve dropped a deuce, all that smelly bacteria is just fermenting in your digestive tract, causing bloating and accumulating stink power. The more time you give the bacteria to metabolize, the deadlier your gas can be when it finds its way out.

Have you ever walked into a bathroom that smells like Satan himself just farted, only to find a giant turd floating in the toilet bowl? The longer that toxic stew of feces sits there, the worse the smell gets—and the same applies to your colon.

6. Digestive Health Issues

Sometimes, smelly farts are your body’s way of telling you something’s off. Here are a few digestive health conditions that can make your gas smell worse than normal.

• Lactose intolerance: The inability to digest dairy products
• Celiac disease: An immune reaction to eating gluten
• Irritable bowel syndrome (IBS): A common condition that causes bloating, bad gas, and constipation
• Inflammatory bowel disease (IBD): A term for two conditions (Crohn's disease and ulcerative colitis) that cause chronic inflammation in the gastrointestinal tract

Is It Healthy For Farts to Smell Bad?

Yes, it’s normal for your farts to stink. In most cases, your deadly fumes are nothing to fear. In fact, they can indicate you’re eating lots of healthy foods like veggies, eggs, and beans. 

That said, if your extra-foul-smelling gas lasts more than a few days, hit up your healthcare provider. You should also get help if you notice weight loss, abdominal pain, or changes in your pooping patterns. These can be warning signs of colon cancer and warrant attention from a gastroenterologist.

How to Stop Your Farts from Smelling So Bad

Spoiler alert: you can’t make your farts smell “good.” But our best advice to make them more bearable is to identify your trigger foods and avoid them like the plague. Does Taco Bell give you ghastly gas? Skip the drive thru if you’ve got an important function coming up.

You should also aim for consistent, complete bowel movements. This lets you expel your excess gas in one sitting, plus you’ll clear out the bacteria-infested poop that’s causing the stench to begin with.

Lastly, avoid carbonated drinks and chewing gum. These pump air into your stomach, increasing the chances you’ll have to rip ass.

Remember: smelly farts are nothing to be ashamed of, so don’t be afraid to let ‘er rip. As Benjamin Franklin said so eloquently about 240 years ago, “Fart proudly.”

(PS—if you're interested in learning how to make yourself fart on command, we have you covered.)