Why do I feel bloated and gassy after eating?

February 20, 2021

Stuck with a stomach that feels like a balloon and tooting louder than a brass band? You’re not alone.

Feeling bloated and gassy after eating is common, especially after a big meal. 

It’s not pleasant (and can also feel very embarrassing!) but is it something to be concerned about? 

We find out what causes bloating and gas after eating, whether it’s a sign of an unhealthy gut, and the steps you can take to reduce it.

The story behind bloating and gas

  • Bloating happens when air or gas gets trapped in your gut
  • It can be caused by taking in air when you eat and drink, or from gas produced by your gut microbes (microbiome)
  • Gas and bloating after eating can be triggered by certain foods, as well as some health conditions
  • Simple changes to how and what you eat can help cut down on bloating and gas

What causes bloating and gas after eating?

Bloating is a term that’s often used to describe a feeling of uncomfortable fullness, having a tight, swollen belly, and feeling gassy after eating. Bloating happens when large amounts of air or gas get trapped in your gut.

So, what causes bloating? 

Eating is a common cause of bloating because our bodies produce gas as they digest food.

We can also end up swallowing air when we eat, which gets trapped in our digestive system. The fizzy gas in carbonated drinks and beer can also make you feel bloated, although it often comes out through burping rather than from the other end of your digestive system.

The gas lower down the gut mainly comes from the trillions of microbes that make up your gut microbiome. As our gut microbes break down components in our food, they release lots of different molecules, called metabolites, as well as gases that we usually get rid of by farting. 

Several factors affect how much gas brews up in the gut. The most obvious is what you’ve eaten, as well as the types and numbers of different microbes living in the gut. Another is the length of time food takes to travel through your gut, known as transit time.

This gut gas is mostly made up of nitrogen, hydrogen, methane, and carbon dioxide, which don’t smell. The classic fart stink comes from the tiny amounts of strong-smelling hydrogen sulfide and other sulfur-containing compounds that are also in there.

Interestingly, not all this gas comes out of your body in this way. It can also be absorbed from the gut into the blood and eventually reaches the lungs where it’s breathed out.

Is it normal to feel bloated and gassy after eating?

Gas from our gut bugs is normal and a sign that we are giving them the foods they need to thrive. We are all different and have unique gut microbes and diets, so some people will produce more gas than others.

Episodes of gassiness and bloating are often due to specific foods or particularly large meals triggering lots of microbial activity and, in turn, lots of gas.

Some people can be more sensitive to the feeling of gas pushing against the walls of the gut (visceral hypersensitivity), causing pain and discomfort, even if their microbes aren’t producing an unusually large amount of gas. 

Excess gas and bloating can sometimes be caused by food intolerances, including lactose intolerance and celiac disease, or certain conditions such as irritable bowel syndrome (IBS) or small intestine bacterial overgrowth (SIBO). 

Rarely, bloating and gut pain can be a symptom of something more serious, including some types of cancer. 

If you experience persistent bloating or pains that cannot be explained by a change in your diet or circumstances (e.g. increased stress), you should speak to your physician.

What foods cause bloating and gas?

When you eat, your microbes get a meal too, consuming fiber from plant-based foods as well as sugars and protein. If you’ve drunk alcohol, your gut microbes will also get a taste, which can be as impactful to them as it is to us.

Some foods that are high in certain types of carbohydrates known as FODMAPs have a reputation for being ‘farty’. This includes beans, lentils, and cruciferous vegetables like broccoli, cabbage, or cauliflower. Onions and bell peppers can also cause gassiness, as well as some fruits. 

However, these are healthy plant-based foods, which help to feed the ‘good’ gut microbes that are associated with better health, so it’s better to keep them in your diet if you can.

Sugar-free foods containing polyols, such as erythritol, sorbitol, or xylitol, can have a dramatic effect on your gut microbes, causing gas, bloating, and even diarrhea.

Food allergies and intolerances can also cause bloating and gas. One of the most common is lactose intolerance, which is a reaction to the sugars found in milk and dairy products. 

How can I reduce bloating and gas after eating?

Gut gas is normal and healthy, especially after eating lots of fibrous plant-based foods or a large meal. And many of us suffer from trapped wind or feeling bloated from time to time.

If feeling bloated and gassy after eating is bothering you, there are some things that you can try.

As a reminder, if you experience persistent bloating or pains that cannot be explained by a change in your diet or circumstances (e.g. increased stress), you should speak to your physician. You should also speak with a health professional if you’re concerned that you might have a food allergy/intolerance or be sensitive to FODMAP foods.

How to improve your gut health

Finding the foods that work best for your unique body and your community of gut bacteria starts with understanding which bugs are living in your gut right now, and which foods will help them thrive. 

Our gut microbiome test is the most advanced available on the market, using a deep level of sequencing to identify the microbes in your gut. We’ll tell you which bugs you’re hosting, together with an in-depth understanding of how your body responds to foods so you can take back control of your health and weight for good.

Want to learn more about your unique microbiome and discover your responses to food? Join the ZOE Program today and start your journey towards a healthier gut. 

Please note:

Our services currently support general wellness and cannot diagnose or treat metabolic, inflammatory, or other diseases.

The current version of our advice is not explicitly designed for people living with irritable bowel syndrome (IBS), though we are working on this. It is known that some people with IBS struggle to adapt to a diet with much higher levels of fiber and more plant diversity. 

Our scientists believe that an unhealthy gut microbiome plays a key role in this, and we learn more with every additional person with IBS who does the ZOE tests. As a result, we are actively researching how to adjust our advice specifically for people living with IBS and other gut conditions in the future. 

While we provide advice to improve gut health and reduce dietary inflammation which is suitable for most people – some parts of our advice might not be suitable for a sensitive gut, so please check in with your physician before trying ZOE.

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