Fact Checked

What Causes a Gassy Stomach?

Patti Kate
Patti Kate

Most people get a gassy stomach due to something they ate or drank. One of the most common causes is carbonated beverages, although many other foods can lead to excess stomach gas production too. Certain illnesses, and even some medications, can cause or contribute to the problem as well. While it can be embarrassing and uncomfortable, stomach gas is usually harmless. It can sometimes be a symptom of an illness or disease, however, so severe or long-term cases should be reported to a medical professional.

A healthy digestive system is packed with billions of bacteria of several different species, some of which produce waste gases by metabolizing undigested food. Also in the digestive system are bacteria which absorb and metabolize these gases, and produce other types of waste. The balance of bacteria present in the digestive system has quite a profound influence on the amount of gas the body expels, and an upset in this balance often leads to excess. Both diet and digestive health play a role in determining the balance of bacteria in the gut.

Eating and Drinking

Beans are one of the most common causes of intestinal gas.
Beans are one of the most common causes of intestinal gas.

One common cause of stomach gas is swallowing more air or gas than normal. For example, drinking any type of carbonated beverage will result in this problem, simply because those drinks contain dissolved carbon dioxide. Gum and hard candy can increase the risk as well, because people tend to swallow more often when chewing or sucking on them. Excess air-swallowing can also occur when eating a large meal, eating quickly, or when food isn't chewed thoroughly.

A diagram showing ulcerative colitis and other colon problems that could cause gas and bloating.
A diagram showing ulcerative colitis and other colon problems that could cause gas and bloating.

Many people experience bloating and flatulence after eating dairy foods. People who are lactose-intolerant cannot easily digest milk sugar, which means that large quantities of lactose pass from the stomach into the colon. The bacteria there metabolize it and produce gas. For similar reasons, a diet that is high in fructose can cause the same issue for some people, and starchy foods, such as potatoes and corn, may cause a gassy stomach.

Lactose, fatty foods and carbonated beverages can create excessive gas in the stomach.
Lactose, fatty foods and carbonated beverages can create excessive gas in the stomach.

Fatty foods can also cause this problem, since it takes the body longer to digest them. This means that the bacteria have more time to work and produce more waste. In addition to being healthier for other reasons, eating fewer foods that are high in fat can allow the stomach to empty more quickly, relieving that gassy feeling.

Increasing dietary fiber intake is a good way to improve digestive health, but it can lead to an increased production of digestive gas. Some of the worst offenders here are beans, broccoli, Brussels sprouts, cauliflower, and cabbage. This excess occurs because dietary fiber is not digested in the stomach, instead passing into the colon, where much of it is metabolized by gas-producing bacteria. A gradual increase in dietary fiber will help alleviate this problem, because it gives both the digestive system and its bacterial population time to adjust to the added fiber.

Illnesses and Medical Conditions

Cutting down on vegetables such as broccoli and cabbage can reduce bloating, gas and belching.
Cutting down on vegetables such as broccoli and cabbage can reduce bloating, gas and belching.

Gastrointestinal diseases often cause a gassy stomach in addition to symptoms such as bloating, cramping, pain, and diarrhea. Such illnesses include irritable bowel syndrome, ulcerative colitis, and Crohn’s disease, as well as infectious diseases such as gastroenteritis. In the case of gastroenteritis, the symptoms typically disappear once the illness has run its course.

Some foods, such as cauliflower, can cause gas.
Some foods, such as cauliflower, can cause gas.

When a chronic condition such as irritable bowel syndrome is the cause, the symptoms are ongoing, and can persist even when treated with medication or dietary modification. This is because chronic gastrointestinal diseases interfere with digestion, and food is more likely to pass through the stomach and into the colon. Treating such conditions is difficult, and a person with one of these chronic illnesses might have to try several medications and dietary changes to come up with a combination that helps control the symptoms.

Medication-Related Causes

Gastrointestinal diseases can cause a gassy stomach and stomach pain.
Gastrointestinal diseases can cause a gassy stomach and stomach pain.

Certain types of medication can cause a gassy stomach either because they interfere with digestion or because they alter the balance of bacteria populations present in the gastrointestinal tract. For example, taking antibiotics can cause digestive issues because these medications are specifically designed to kill bacteria. Broad-spectrum antibiotics are typically the culprits here because they can be metabolized by a wide range of species. Other types of medication, including some drugs used to treat Type 2 diabetes, can lead to increased gas production too, because they block carbohydrate digestion in the stomach.

Carbonated beverages may cause a gassy stomach.
Carbonated beverages may cause a gassy stomach.

When antibiotics are to blame, the symptoms will typically resolve over time, once the course of medication has been completed. Taking probiotic supplements or eating live-culture yogurt for a few days can help improve the situation, as these will help replenish the body’s populations of gas-absorbing bacteria. Probiotics, as well as over-the-counter gas-reducing formulations, can also be useful when medications have to be taken long term.

Diagnosing Stomach Gas Causes

Persistent gas and bloating may signal irritable bowel syndrome (IBS) or another underlying health concern.
Persistent gas and bloating may signal irritable bowel syndrome (IBS) or another underlying health concern.

In most cases, the causes of excess gas can be pinned down to an innocuous reason, such as a change in diet or eating habits. Some causes are more serious, however, so it’s a good idea for anyone who has symptoms that last longer than a week or two or are accompanied by other digestion problems to talk to a medical professional. Common signs of a more serious problem include symptoms like severe stomach pain, bloody stool, a fever, vomiting, and chest pain.

If the health care provider suspects a more serious medical condition might be causing the symptoms, she might order blood tests or an imaging test, such as an ultrasound of the stomach. In some cases, a computerized tomography (CT) or magnetic resonance imaging (MRI) might help diagnose the cause.

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Discussion Comments


Help! At first I thought staying away from dairy products was going to fix my gassy stomach problem. I cut them out, but after months, I was still having issues. Then, I though it was all caused by fast food and other foods full of fat. So I cut them out too.

I ate nothing but vegetables, fruits, beans and proteins -- until I learned that beans are not good either. So I cut them out, too.

A few weeks after, I had to stop eating some of my favorite vegetables such as lettuce, broccoli, cauliflower, etc. because I read they were bad too.

For the last month, I've been eating literally nothing but tomato and carrot salad with canned tuna, and I'm still full of gas!

I'm seriously tired of this. I eat at least four serving of fruit and two or three servings of vegetables a day. I never eat carbohydrates, never. I'm eating the healthiest diet I ever have, and I still get tortured with horrible pains and gas. Help, please -- seriously.


I'm so worried. I'm producing a lot of gas and it happens at night. I'm newly married and thus my hubby is also getting concerned. Please help.


@JimmyT - I had a similar situation happen to me, and it still does happen fairly regularly. I think I have traced mine to eating salads. I work in a hospital with a cafeteria, and they always have a salad bar. A lot of times, when none of the other stations have anything good, I will get a salad from there. Whenever I'm finished, I will need to belch a few times to even things out.

I've noticed it with some other foods, but mainly salads. I know cucumbers are a common food that causes gas, but even without those, I still notice it. Maybe it's something about the lettuce. In your case, can you trace it to any individual food?

The only other thing I can think of is that maybe you are eating faster there than you might otherwise eat at home or something. I know eating faster gives food less time to settle at first, and will cause belching when it does finally settle.


The problem I have noticed lately is that after I eat a big meal, I always burp a lot. Does anyone have any idea what might cause this?

I didn't notice it happening until about a year ago. We have a cafeteria in the building where I work, and it started happening after I started going there for lunch. At first, I thought it was simply because I was drinking a soft drink with my meal. I stopped that, though, and the burping continued.

I don't really know what else it could be. It's not like I eat the same thing every day, but it seems to be linked to the cafeteria, because it doesn't happen at other places. I should also mention that it stops after about 10 minutes, so it's not like it is negatively affecting my life or anything.

@TreeMan - I find that I have the same problem with milk sometimes. Your theory makes sense even though I don't really know anything about biology.

I love that they have come out with the yogurts with probiotics now. I know yogurt has usually always had some level of probiotics, but now a lot of brands are specifically adding more bacteria and using that as a selling point. I notice that it does help my stomach feel better after I have a big meal.

Like the article mentions, greasy foods are a big problem for me. I avoid eating fast food as much as possible. Whenever I do go out, though, I usually have a yogurt afterward, and that helps me feel a little better if I have a bloated stomach.


@myharley - I know what you mean about milk. It seems like that is a common problem people are mentioning. At least in my case, I don't have any problem with other dairy products, so I know I am not lactose intolerant.

I am guessing that in my case the problem comes from drinking too much milk in a short time period. I usually drink a glass of milk with my dinner every night, and that is fine, because it mixes with my food or whatever. Sometimes at night, though, I'll get thirsty for some milk and will drink a whole glass all at once. That's when I start to get gas and bloating.

I'm guessing I might be experiencing some of the same symptoms as someone who is lactose intolerant, though. There are only so many of the enzymes that break down milk, and if I drink a whole glass, maybe it can't process it that fast. That's my theory, at least.


I've heard that some supplements, herbs and spices can cause excess gas too. Although foods and using antibiotics too much seem to be the main causes for me.

I don't know if anyone else experiences this, but fish and some other sea foods give me gas. I have no idea why. Fish doesn't immediately occur to me as a gas causing food. But I've paid attention to this and whenever I have fish- whatever kind it is- I always have bad gas and bloating afterward.

The other reason why I've had bad bouts of gas before is because of long antibiotic use. I get sinus infections often and I'm put on antibiotics to clear them up. After I use antibiotics, I go through a period where I have too much gas all the time.

My doctor said that this happens because antibiotics kill many bacteria in the stomach- both good and bad. It goes back to normal after a month or so, but I do have a gassy stomach for a while until the balance in bacteria is restored.


I used to be able to eat anything and not have any problems. My sister was just the opposite, and always seemed to have a sensitive stomach.

Now that I am older, I have noticed I can't eat everything I used to without having some side effects.

If I eat too fast or have a big heavy meal, I notice that I have excess gas. It took awhile before I realized what was causing this. There are so many times I gulp down my food so fast and am not even thinking about what I am eating.

I have learned to concentrate on eating slower and really enjoying the taste of my food. One tip my sister gave me for a gassy stomach is to take a little bit of organic apple cider vinegar with some water and honey.

Some people can't handle the taste of this, but with the honey, it isn't too bad. If I drink this in a big glass of water before a meal, it really helps keep my indigestion and gassy stomach under control.


@SarahSon - I understand what it feels like to have a gassy bloated stomach and feel miserable.

For me, dairy products were my biggest problem. This was frustrating for me because I love cheese, milk, ice cream and yogurt.

I noticed that whenever I had these, I would get sharp pains in my stomach and feel like I had indigestion.

Come to find out, I was lactose intolerant and that is what was causing all my problems. When I eliminated those foods from my diet, my symptoms went away.

There are some alternative products that are available for people who are lactose intolerant, but they just don't taste the same.

I did start taking a probiotic supplement to help with the digestion process of the foods I eat. You often wonder if something like this really works. When I ran out and didn't take any for about 2 weeks, I noticed I had a gassy stomach after eating a heavy meal.

This is motivation for me to stay away from the dairy products, and take some probiotics every day.


It can be really embarrassing if you have a gassy stomach when you are around other people. I have found the two foods that cause gas for me are beans and vegetables.

I have learned to pass on these foods if I am in public. Not only do I feel miserable afterward, but don't like to put myself in embarrassing situations like this.

I really found this out when I was trying to add more fiber to my diet. Both beans and vegetables can be a good source of fiber, but I was adding it too quickly.

If you start out slowly and give your body more of a chance to adjust, it isn't quite as bad. I like the full feeling I have after eating high fiber foods, but try to avoid the gassy stomach as often as possible.


I have always loved drinking pop, and to me, there is nothing better than a cold Pepsi. I never would have guessed this was the reason for my gassy stomach pain.

I thought it was because of certain types of food I was eating, but every time I drank a Pepsi, I noticed I would get a gassy stomach.

I put up with this for awhile before I decided to have it checked out. My doctor told me that carbonated beverages often were a factor in feeling gassy or bloated.

Giving up drinking pop was really hard for me, but I got tired of feeling bad every time I had one. I give in every now and then, but know that drinking a lot of pop isn't good for me whether it gives me gas or not.

I dated a guy who had Crohn's disease, and it made his life absolutely miserable. He seemed to have a bloated stomach all the time, and he frequently had diarrhea with little warning.

He had trouble keeping a job because he had to call in sick so often. We couldn't go out to eat at many places, because the food would irritate his stomach, and he would have to rush to the bathroom.

He told me that the gas pains were the worst thing about the disease. Having trapped gas can be so painful, and the gas can make the moments before diarrhea feel even worse because of all the cramping it can cause. I really felt bad for him, because the few times that I have dealt with an extremely gassy stomach have been horrible, so I can't imagine having it all the time.


I discovered a good pill for the prevention of gas accidentally. I had been having problems with yeast infections, and my doctor recommended that I start taking daily acidophilus supplements.

The supplements have the same live cultures that you find in yogurt. I absolutely hate the taste of yogurt, so the pills are ideal for me. The cultures are supposed to help prevent yeast infections, but I read on the label that they also promote digestive health.

Since I have been taking the supplements, I haven't had my usual problems with bloating and discomfort. Even if I get to a point where I no longer need the supplements for yeast infections, I will continue taking them for their digestive benefits.


@OeKc05 – Though cutting out fast food can definitely help your stomach, some people have problems even after they switch to a healthy diet. I switched to eating lots of healthy foods, but I still seemed to have gas pains and general stomach discomfort.

I discovered that portion size was the problem. I started eating about half to two-thirds of what I normally consumed, and the gas started to go away.

I had been packing too much food into my stomach without realizing it. Now that I've figured this out, I can eat whatever type of food I want, as long as I only eat a little of it.

This has also made me lose weight. Though my eyes usually disagree with my stomach on how much I should have on my plate, my brain wins out in the end, and my stomach is grateful afterward.


I have discovered that eating fast food causes a gassy stomach ache for me. The greasier and fattier the meal, the worse the gas and bloating will be.

I used to eat stuff like this as a teenager with no problem. However, my body seems to have changed over the years, and I can no longer tolerate loads of fries and burgers.

I eat so much healthier now, and I don't have problems with gas. I probably get three servings of fruit a day, along with two of vegetables. I eat lean meat and whole grain breads and cereals.

Since my diet has changed so drastically, I can really tell a difference if I do have a greasy fast food meal occasionally. I can count on a gassy stomach to follow the meal, and I will be miserable for hours afterward, so I try to avoid this.


@feruze-- There are a lot of things that might be going on. I suggest you see your doctor to figure out the cause.

I have lactose intolerance so I know how you feel. Anything with milk causes flatulence, excessive gas in my stomach and bowels. I usually get diarrhea too. It's really embarrassing if I'm around other people. I believe gluten intolerance has similar effects. If someone who is allergic to gluten has it, they also have things like gas, bloating and diarrhea.

So it's best to find out if you have an allergy first. It might just be one type of food that's setting you off and you don't realize it. And if you are intolerant of lactose, you can take your probiotics in supplement or powder form. That's what I do.


I think I must have a really sensitive stomach because so many foods cause bloating and gas for me. All beans and lentils are on top of the list. Some vegetables like cabbage and cauliflower cause me gas and bloating, so does yogurt. I also discovered the other day that lamb meat gives me gas too.

All of these foods are pretty healthy foods and I try to avoid junk foods as much as possible. But I can't seem to have a regular meal like everyone else without being uncomfortably bloated afterward. I do use over-the-counter medications for this, but they don't seem to help that much.

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    • Beans are one of the most common causes of intestinal gas.
      Beans are one of the most common causes of intestinal gas.
    • A diagram showing ulcerative colitis and other colon problems that could cause gas and bloating.
      By: Alila
      A diagram showing ulcerative colitis and other colon problems that could cause gas and bloating.
    • Lactose, fatty foods and carbonated beverages can create excessive gas in the stomach.
      By: Balint Radu
      Lactose, fatty foods and carbonated beverages can create excessive gas in the stomach.
    • Cutting down on vegetables such as broccoli and cabbage can reduce bloating, gas and belching.
      By: monticellllo
      Cutting down on vegetables such as broccoli and cabbage can reduce bloating, gas and belching.
    • Some foods, such as cauliflower, can cause gas.
      By: ExQuisine
      Some foods, such as cauliflower, can cause gas.
    • Gastrointestinal diseases can cause a gassy stomach and stomach pain.
      By: Ljupco Smokovski
      Gastrointestinal diseases can cause a gassy stomach and stomach pain.
    • Carbonated beverages may cause a gassy stomach.
      By: Brent Hofacker
      Carbonated beverages may cause a gassy stomach.
    • Persistent gas and bloating may signal irritable bowel syndrome (IBS) or another underlying health concern.
      By: Alliance
      Persistent gas and bloating may signal irritable bowel syndrome (IBS) or another underlying health concern.