Passing gas 14 to 23 times a day is completely normal for a healthy adult. If you feel like you’re passing gas constantly, you may actually be within that range and just noticing it more, or something in your diet or daily habits could be pushing you above it. Either way, the cause almost always comes down to what you eat, how you eat, or how your gut bacteria process what you give them.
How Gas Forms in Your Gut
Gas in your digestive tract comes from two sources: air you swallow and gases your gut bacteria produce. When you eat carbohydrates that your small intestine can’t fully break down, those undigested sugars travel to your large intestine, where trillions of bacteria ferment them. That fermentation produces hydrogen, carbon dioxide, and sometimes methane. These three gases, along with nitrogen and oxygen from swallowed air, make up over 99% of flatulence. None of them actually smell.
The odor comes from tiny amounts of sulfur-containing gases, particularly hydrogen sulfide, along with compounds called skatoles and indoles. So if your gas is frequent but odorless, your gut bacteria are doing their normal work. If it smells, sulfur-rich foods like eggs, cruciferous vegetables, or meat are likely contributors.
Foods That Produce the Most Gas
Certain short-chain carbohydrates are poorly absorbed in the gut and are the biggest gas producers. Researchers at Monash University group these under the term FODMAPs, and they work in a predictable way: they move slowly through the small intestine, drawing in extra water, then arrive in the large intestine where bacteria ferment them rapidly. The result is a combination of gas and intestinal stretching that causes bloating, cramping, and flatulence.
The main categories and their common food sources:
- Fructans and GOS: wheat, rye, onions, garlic, and legumes like beans, chickpeas, and lentils
- Lactose: milk, soft cheeses, yogurt, and ice cream
- Fructose: honey, apples, pears, and foods made with high-fructose corn syrup
- Sugar alcohols (sorbitol and mannitol): stone fruits, mushrooms, cauliflower, and sugar-free gums or candies
Fiber is another major factor. High-fiber foods are genuinely good for your health, but adding too much too quickly overwhelms your gut bacteria, leading to a temporary spike in gas production. If you recently started eating more whole grains, vegetables, or a fiber supplement, that’s likely your answer. Increasing fiber gradually over a few weeks gives your gut bacteria time to adjust, and the excess gas typically settles down.
Habits That Make You Swallow Air
Not all gas starts in the large intestine. A significant portion comes from air you swallow throughout the day, a process called aerophagia. Most of this air gets burped back up, but whatever passes into your intestines eventually comes out the other end. Common habits that increase air swallowing include eating too fast, talking while you eat, chewing gum, sucking on hard candy, drinking through a straw, smoking, and drinking carbonated beverages. If your gas doesn’t smell much, swallowed air may be a bigger contributor than bacterial fermentation.
This is one of the easiest causes to fix. Slowing down at meals, putting your fork down between bites, and cutting back on carbonated drinks can make a noticeable difference within days.
Lactose Intolerance and Other Sensitivities
If your gas consistently gets worse after dairy, you may not produce enough of the enzyme that breaks down lactose. Lactose intolerance is extremely common, affecting a majority of adults worldwide, and symptoms typically appear within a few hours of eating or drinking dairy products. The undigested lactose passes into the large intestine and gets fermented, producing a reliable burst of gas, bloating, and sometimes diarrhea.
A simple way to test this is to cut dairy for a week and see if your symptoms improve. If they do, you can experiment with how much lactose you tolerate. Hard cheeses and butter contain very little lactose and rarely cause problems. Lactase enzyme supplements taken before a meal can also help if you don’t want to avoid dairy entirely.
A similar pattern applies to fructose. Some people absorb fructose poorly, and eating high-fructose foods like apples, honey, or products sweetened with high-fructose corn syrup triggers the same fermentation process. If gas tends to follow fruit or sweetened foods rather than dairy, fructose malabsorption is worth considering.
What Actually Helps Reduce Gas
Over-the-counter remedies are a mixed bag, and it’s worth knowing which ones have real evidence behind them. An enzyme supplement containing alpha-galactosidase (the active ingredient in products like Beano) has been shown to reduce bloating and gas when taken before eating fermentable carbohydrates like beans, bran, or certain fruits. It works by breaking down those hard-to-digest sugars before they reach the bacteria in your large intestine.
Simethicone, the ingredient in many popular gas relief products, is a different story. Despite being widely recommended, studies have not shown a benefit for ordinary flatulence. It works by breaking up gas bubbles in the stomach, which may help with belching or a feeling of upper abdominal fullness, but it doesn’t reduce the gas produced by bacterial fermentation in the lower gut.
Activated charcoal taken by mouth has shown inconsistent results, and recent trials haven’t supported its use. Interestingly, charcoal-lined undergarments are a different matter. In testing, charcoal briefs absorbed nearly 100% of sulfur gases, and charcoal pads worn inside regular underwear captured 55 to 77%. These won’t reduce how often you pass gas, but they can eliminate the odor.
For sulfur-smelling gas specifically, bismuth subsalicylate (the active ingredient in Pepto-Bismol) can bind over 95% of sulfide gases in the gut when taken at standard doses. This targets odor rather than frequency.
Identifying Your Personal Triggers
Because so many foods can cause gas, the fastest way to figure out your specific triggers is a short elimination approach. Pick the most likely category based on your diet. If you eat a lot of beans, onions, or garlic, try reducing those for a week. If dairy is a daily staple, cut it out temporarily. If you recently increased your fiber intake, scale it back and add it more gradually.
Keeping a simple food diary for a week or two can reveal patterns you wouldn’t notice otherwise. Write down what you eat and when you notice gas or bloating. Most people find that two or three specific foods are responsible for most of their symptoms, and reducing those foods brings things back to a comfortable baseline without requiring a restrictive diet.
Signs Something Else Is Going On
Excessive gas on its own is rarely a sign of anything serious. But if your gas is accompanied by persistent abdominal pain, unexplained weight loss, chronic diarrhea or constipation, or a sudden change in your symptoms after years of normalcy, those combinations can point to conditions like irritable bowel syndrome, celiac disease, or other digestive disorders that benefit from proper evaluation. A sudden shift in your pattern, not just “more gas than I’d like,” is the key signal worth paying attention to.