Most people pass gas between 13 and 21 times a day, and the two main sources are swallowed air and bacterial fermentation in the large intestine. Reducing gas comes down to limiting both: eating in ways that minimize the air you take in, and adjusting your diet so fewer undigested carbohydrates reach your colon for bacteria to feed on.
Where Intestinal Gas Comes From
Five gases make up more than 99% of what your body expels: nitrogen, oxygen, carbon dioxide, hydrogen, and methane. The signature smell comes from tiny amounts of hydrogen sulfide and a few other trace compounds. Understanding the three sources of gas helps you target the right fix.
The first source is swallowed air. Every time you swallow food, liquid, or saliva, a few milliliters of air come along for the ride. Most of this collects in the stomach and comes out as burping, though some travels further down. The second source is chemical reactions in the upper gut, where digestive secretions interact and release carbon dioxide. The third, and by far the largest, is fermentation. When carbohydrates escape digestion in the small intestine, bacteria in the colon break them down and produce hydrogen, methane, and carbon dioxide as byproducts. This fermentation is the primary driver of flatulence.
Stop Swallowing Extra Air
A surprising amount of gas starts before food even hits your stomach. These everyday habits increase how much air you swallow:
- Eating too fast or talking while eating
- Chewing gum or sucking on hard candy
- Drinking through straws
- Carbonated beverages, which deliver carbon dioxide directly into your stomach
- Smoking
The fix is straightforward. Chew your food slowly, finish one bite before taking the next, and sip from a glass rather than a straw. Save conversation for after the meal rather than between bites. If you’re a habitual gum chewer, dropping that one habit alone can make a noticeable difference within days.
Foods That Produce the Most Gas
Certain carbohydrates are poorly absorbed in the small intestine, which means they arrive in the colon intact and become fuel for gas-producing bacteria. These are sometimes grouped under the term FODMAPs, and knowing the main categories helps you identify your personal triggers.
Beans and legumes are the classic offenders. Red kidney beans, split peas, baked beans, and falafels are especially high in a sugar called GOS that your small intestine can’t fully break down. Certain vegetables are rich in fructans or mannitol: garlic, onion, leek, artichoke, mushrooms, and celery top the list. Fruits high in excess fructose or sorbitol include apples, pears, cherries, mangoes, watermelon, peaches, plums, and dried fruit. Wheat-based grains like wholemeal bread, rye bread, wheat pasta, and wheat-based muesli contain fructans as well. And dairy foods high in lactose, such as milk, soft cheeses, and yogurt, cause gas in people who don’t produce enough of the enzyme that digests lactose.
You don’t need to eliminate all of these permanently. The practical approach is to cut back broadly for two to three weeks, then reintroduce foods one at a time. Most people find that only a handful of items are real problems for them, and the rest can go back on the plate.
Walk After You Eat
A short walk after meals helps your gut move gas through and out more efficiently. Your bowel moves on its own, but it moves better when you move. Walking stimulates the muscles of the intestinal wall, helps the stomach empty faster, and reduces the bloated feeling that comes from gas sitting in one place too long. Even 10 to 15 minutes of light walking after dinner can make a real difference. This is low effort and no cost, which makes it worth trying before anything else.
Over-the-Counter Options That Help
If diet and habit changes aren’t enough on their own, a few products can fill in the gaps.
Simethicone
Simethicone (sold as Gas-X and similar brands) works by breaking up gas bubbles in your stomach and intestines so they’re easier to pass. It doesn’t prevent gas from forming, but it relieves the pressure and bloating once gas is already there. The typical adult dose is 40 to 125 mg taken after meals and at bedtime, up to 500 mg per day.
Alpha-Galactosidase Enzyme
This is the enzyme sold as Beano and generic equivalents. It breaks down the complex carbohydrates in beans, broccoli, cabbage, cauliflower, Brussels sprouts, onions, and similar vegetables before they reach the colon, so bacteria have less to ferment. The key is timing: you take it right before your first bite or within 30 minutes of eating. It won’t help if you take it hours later.
Lactase Supplements
If dairy is one of your triggers, a lactase supplement taken with your first sip of milk or bite of cheese supplies the enzyme your body is short on. This is especially useful for people who don’t want to switch entirely to lactose-free products.
Peppermint Oil for Bloating and Discomfort
Enteric-coated peppermint oil capsules have solid clinical evidence behind them. In a randomized, placebo-controlled trial, 75% of participants taking peppermint oil capsules twice daily for four weeks saw their bloating and gas symptoms drop by more than half, compared with 38% in the placebo group. The benefits also persisted for at least a month after stopping. The enteric coating matters because it lets the capsule pass through the stomach and release in the intestine, where it relaxes the smooth muscle of the gut wall and helps trapped gas move along. Plain peppermint tea is milder but can still help with mild symptoms.
Probiotics Worth Trying
Not all probiotics are equal for gas. The strain with the most targeted evidence is Bifidobacterium infantis 35624, which has been studied specifically for reducing bloating and abdominal discomfort. In clinical trials, participants taking a moderate dose showed meaningful improvement in bloating scores compared to placebo. The key word is “strain-specific.” A generic probiotic blend may or may not contain the right organisms, so look for the specific strain on the label. Give any probiotic at least four weeks before deciding whether it’s working for you.
Other Habits That Add Up
Smaller meals put less undigested material into your colon at once, which means less fermentation per sitting. Cooking vegetables thoroughly also breaks down some of the fibers that bacteria feed on, making cooked broccoli easier on the gut than raw. If you’re increasing fiber in your diet for other health reasons, ramp up slowly over a few weeks rather than jumping to a high-fiber diet overnight. A sudden increase is one of the most common causes of a temporary spike in gas.
Stress and anxiety can also increase air swallowing without you realizing it. People under stress tend to take shallower breaths, swallow more frequently, and eat faster. Addressing the stress may indirectly reduce gas in ways that dietary changes alone won’t.
Signs That Gas May Signal Something Else
Ordinary gas, even when frequent, is rarely a sign of a serious problem. But certain symptoms alongside gas warrant attention: blood in your stool, unexplained weight loss, persistent nausea or vomiting, significant changes in bowel habits (new constipation or diarrhea), or prolonged abdominal pain. Chest pain with gas-like symptoms also needs prompt evaluation, since it can mimic or mask cardiac issues.