Passing gas between 14 and 23 times a day is completely normal. If you’re noticing it more than that, or it feels like a recent change, the cause is almost always something you’re eating, drinking, or doing without realizing it. Less commonly, it points to a digestive issue worth investigating.
Where the Gas Actually Comes From
Your body produces gas through two main routes. The first is swallowed air. Every time you eat, drink, or swallow saliva, a small amount of air travels into your stomach. Most of it comes back up as a burp, but some continues into the intestines and exits the other way.
The second source, and the bigger one for most people, is fermentation in your large intestine. Trillions of bacteria live there, and their job is to break down the carbohydrates your small intestine couldn’t absorb. When they do, they produce gas as a byproduct. The more undigested material that reaches your colon, the more gas those bacteria generate.
Habits That Make You Swallow Extra Air
You might be taking in far more air than you realize. Eating too fast, talking while you eat, chewing gum, sucking on hard candy, drinking through a straw, and smoking all increase the amount of air you swallow. Carbonated drinks add gas directly on top of that. If you’ve picked up any of these habits recently, or do several of them daily, the extra air alone can explain a noticeable uptick in flatulence. Slowing down at meals and cutting out gum or straws for a week is often enough to tell whether swallowed air is a major factor for you.
Foods That Feed Gas-Producing Bacteria
Certain carbohydrates are especially difficult for your small intestine to break down. When they pass through undigested, your colon bacteria feast on them and produce significantly more gas. These carbohydrates fall into a group sometimes called fermentable short-chain carbohydrates, and they show up in a surprisingly wide range of everyday foods:
- Beans, lentils, onions, garlic, and wheat products contain soluble plant fibers that are highly fermentable.
- Dairy products contain lactose, a sugar many adults can’t fully digest.
- Fruits contain fructose, which some people absorb poorly (more on this below).
- Sugar-free gum, mints, and diet foods often contain sugar alcohols like sorbitol and xylitol, which go straight to the colon for fermentation.
A high-fiber diet is genuinely good for your health, but if you’ve recently increased your fiber intake, your gut bacteria need a few weeks to adjust. Ramping up gradually gives them time to adapt without producing as much gas in the process.
Why Some Gas Smells Worse Than Others
Most intestinal gas is odorless, made up of hydrogen, carbon dioxide, and sometimes methane. The smell comes from tiny amounts of sulfur-containing compounds, particularly hydrogen sulfide. Your gut bacteria produce hydrogen sulfide when they digest proteins, both from animal and plant sources. Foods rich in sulfur compounds, like eggs, cruciferous vegetables (broccoli, cabbage, cauliflower), and red meat, tend to produce the most pungent gas. If smell is your main concern rather than volume, cutting back on these foods for a few days can make a clear difference.
Food Intolerances You Might Not Know About
Lactose intolerance is common and often develops gradually in adulthood. If you lack enough of the enzyme that breaks down lactose, the sugar passes intact into your colon, where bacteria ferment it into gas. You don’t have to be completely intolerant for this to matter. Even a partial deficiency can mean that a large glass of milk or a bowl of ice cream produces noticeably more gas than your body can handle quietly.
Fructose malabsorption works in a similar way. Your small intestine has a limited capacity to absorb fructose, and some people hit that limit more easily than others. When excess fructose builds up in the intestine, it draws in extra water and travels to the colon, where bacteria ferment it and produce hydrogen gas. High-fructose fruits (apples, pears, mangoes), honey, and products sweetened with high-fructose corn syrup are common triggers. If you notice more gas after fruit-heavy meals or sweetened drinks, fructose could be the issue.
Both of these intolerances can be tested for with a hydrogen breath test, but many people figure it out simply by removing the suspect food for two to three weeks and tracking the results.
Digestive Conditions That Increase Gas
When gas is persistent, excessive (consistently above 23 times a day), and doesn’t respond to dietary changes, a digestive condition may be involved.
Small intestinal bacterial overgrowth, or SIBO, occurs when bacteria that normally live in your colon colonize your small intestine instead. Because they encounter food earlier in the digestive process, they ferment carbohydrates that would normally be absorbed before reaching the colon. The result is more gas, more bloating, and often diarrhea or cramping on top of it. SIBO is diagnosed with a breath test and is treatable.
Irritable bowel syndrome (IBS) frequently involves excessive gas, along with alternating constipation and diarrhea, bloating, and abdominal discomfort. Many people with IBS find that their symptoms improve significantly on a diet that limits the highly fermentable carbohydrates described above. Celiac disease, where the immune system reacts to gluten, can also cause persistent gas because it damages the lining of the small intestine and reduces its ability to absorb nutrients properly.
Practical Steps to Reduce Flatulence
Start with the simplest changes first. Eat more slowly, chew with your mouth closed, and cut out gum and carbonated drinks for a week. If that doesn’t help, look at your diet. Keep a basic food diary for a week or two, noting what you eat and when you feel the most gassy. Patterns tend to emerge quickly, especially with dairy, beans, onions, garlic, and artificially sweetened products.
If you suspect a specific food group, try eliminating it for two to three weeks and then reintroducing it. This is more reliable than removing everything at once, because it tells you exactly which foods are responsible. Over-the-counter products that contain the enzyme for breaking down lactose can help if dairy is the trigger. Products designed to break down the complex sugars in beans can reduce gas from legumes specifically.
If your gas came on suddenly, is accompanied by abdominal pain, unexplained weight loss, persistent diarrhea or constipation, or represents a clear change from your normal pattern, those are signs worth bringing to a doctor. In most cases, though, excessive gas traces back to something identifiable in your diet or daily habits, and adjusting it brings relief within days.