If you’ve ever sprawled on the couch post-meal and felt the urge to burp or fart more than usual, you might wonder if lying down after eating causes gas production to skyrocket. While there are a lot of medical mysteries out there, this thankfully isn’t one of them. You definitely might feel gassier if you lie down after eating, but interestingly enough, it’s not because being in this position directly increases how much gas you make.
Instead, there are a few other very real reasons why you feel all gassed up when you lie down after eating. As with many of the body’s less delightful (but still entirely normal) functions, the processes involved are pretty fascinating.
Let’s talk about how and why you burp.
Having gas is one of those shared experiences that unites human beings. “All living people produce gas,” Christine Lee, M.D., a gastroenterologist at the Cleveland Clinic, tells SELF. In general, most people create an almost impressive one to three pints of gas per day, according to the Cleveland Clinic.
You produce a lot of this gas when you naturally swallow air as you breathe, Dr. Lee explains. That air often exits your body the same way it entered: through your mouth. According to the Cleveland Clinic, burping is the more common way to expel gas from the body. In fact, it can be normal to burp up to 20 times a day, according to the Mayo Clinic. You might be more likely to burp a lot if you drink a lot of carbonated beverages, too.
However, as you and your butt both know, gas can also make a journey from your mouth to your anus.
Here’s how the food you eat sometimes leads to farts.
Some of the air you swallow will stick around in your stomach before you eventually let it out as a fart, the Cleveland Clinic explains. (Or produce flatus, if you’re into medical terms.) But the normal digestive processes in the colon (large intestine) play an even bigger role in farting than swallowed air does.
Your stomach and small intestine digest much of the food you consume, according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). When your body has difficulty digesting carbohydrates including sugar, starches, and fiber—as well as any nutrients you may not tolerate well, like lactose—that food passes undigested into your colon.
Normal, healthy bacteria in the colon work to break down that food, and this naturally creates gases including hydrogen and carbon dioxide, according to the Cleveland Clinic. Some of this gas remains in the GI tract, where it can cause symptoms like uncomfortable abdominal bloating and pain. Some jostles through your GI tract due to peristalsis (the muscle contractions in your digestive tract after you consume food), then exits the body as flatulence. If the bacteria in your colon created enough sulfur while producing those gases, that unmistakable fragrance may blow your cover even if your fart was totally silent.
Some different medical bodies have different takes on normal farting frequency, but usually not by much. For instance, according to the Cleveland Clinic, it’s perfectly normal to fart anywhere from 14 to 23 times a day. The Merck Manual puts this number at 13 to 21 times a day. Either way, that’s a lot of farting.
What you eat may influence your farting frequency. According to the NIDDK, certain foods including beans and cruciferous vegetables like broccoli and Brussels sprouts tend to produce more gas than others during digestion. That catchy song about beans being musical is surprisingly scientifically accurate for some people.
So, why does lying down after eating seem to make you so gassy?
No matter your physical position, it’s normal to feel gassier after a meal because you swallow more air when you eat and drink, especially if you’re talking. Since swallowed air most often comes back up through your mouth, if you do expel this gas, it will frequently manifest as a burp. (Eating won’t produce an uptick in flatulence right away since it typically takes between six and eight hours for food to make it to the colon where bacteria can work its magic.)
Beyond that, the phenomenon of feeling gassier when lying down post-meal may be based in part on perception, Dr. Lee explains. Going about your busy life can distract you from how your body feels, she says. If you’re lying down and not as active, you can become more aware of your body—and your gas.
Then there’s the actual physics of being horizontal. It may be easier for gas to accumulate into larger, more noticeable pockets when you’re lying down, Dr. Lee says. When you’re upright or moving around, the gravitational pull from your vertical orientation and your constant jostling keep little gas bubbles scattered throughout the GI tract, Dr. Lee says. Those influences aren’t as potent when you’re still and lying down, so those bubbles can become consolidated into larger masses, Dr. Lee explains, making your gas feel more noticeable.
While lying down can make you super in tune with your gas, it can also make it harder to expel that air. Lying down puts pressure on the anal opening in a way that can make it a little tougher to naturally pass gas, Dr. Lee explains. “It is also harder to burp lying down as gravity hinders gas traveling up from the stomach to the esophagus,” she says.
Due to this mix of factors, lying down after eating might make you feel like a sentient gas bubble who has to try a little harder than usual to burp or fart.
When is gassiness after a meal a reason to worry?
Although most cases of post-meal gas are completely normal, Dr. Lee recommends checking in with a doctor if this is something new for you, if it’s accompanied by other symptoms (like serious stomach pain, constipation, or diarrhea), or if it just really bothers you.
“If you’ve been OK for years and then started having excessive gas six months ago… something may be going on,” Dr. Lee says.
A few conditions that can cause excessive gas (often in addition to other digestive symptoms such as stomach discomfort or diarrhea) include small intestinal bacterial overgrowth (SIBO), celiac disease, IBS, and lactose intolerance. Seeing a medical expert can help you pinpoint the specific cause of your excessive gas if necessary.
What if you’re pretty sure your post-meal gas is just your body doing its thing, but you still want to try to tame your symptoms? Gastroenterologists happen to have a few clutch strategies for getting rid of gas discomfort right this way.