woman suffering with a bloated stomach - what is the cause?

What causes a bloated stomach?

Are your jeans feeling tighter around your middle? You may be wondering if your added girth is excess fat or is it a bloated stomach?

“I’m so bloated,” is a phrase we’ve all said after a big meal sparks that familiar feeling of fullness. But what happens when this feeling lasts longer than the time it takes to digest a heavy meal? Or even when you’ve been meticulous about your commitment to eating clean. Over-indulgence is simply one of many causes of a bloated stomach. So, what else is your gut telling you when it starts to bulge?

The first step towards finding a way to help with your bloating is to understand what could be causing it to happen. Here we explore, what causes a bloated stomach?

What is bloating?

Bloating is the sensation when your stomach fills with gas. When your tummy feels blown out and the waist bands of clothing suddenly get tighter.  For some people bloating actually makes the tummy look more rounded and bigger.1,2

Symptoms of bloating

  • Tummy feels stretched, full and uncomfortable
  • Flatulence
  • Burping
  • Clothes feel tighter
  • Tummy looks bigger
  • Stomach gurgling and rumbling

What causes a bloated stomach?

It can happen to anyone. We all carry a certain amount of gas in our digestive system. For example, when we chew, gulp and talk, we ingest some small amounts of air. This can cause gas to travel into our gut. If a disproportionate amount of gas is produced in the abdomen for some reason, your body may struggle to excrete this excess air. And if your digestive system is sensitive to these changes, bloating is one of the side effects.

For some people, bloating is only a sensation. For others, it’s accompanied by a physical expansion of the stomach area. So, if bloating is causing you to seek solace in the comfort of looser clothing, you’re probably experiencing abdominal distension. This is where the abdominal muscles relax to relieve the discomfort caused by the gathering gas in the abdomen. This muscle distention allows your stomach to expand.

5 common causes of a bloated stomach3

  • Swallowing too much air
  • Food (certain types of food are more likely to cause bloating)
  • Menstrual cycle
  • Food intolerances or allergies (e.g. lactose and gluten)
  • Digestive conditions

What happens to air inside your gut

When you chew food, gulp down a drink or talk, you swallow air. Certain activities can also increase your intake of air, such as chewing gum, drinking fizzy drinks, and smoking. Stress can also make you swallow air more frequently or in a higher amount.4

Once air travels down into your oesophagus, where does it go next? The result is often burping and flatulence (less politely known as farting).

Diet and bloating

The festive period is a common time to experience bloating, for the obvious gluttonous reasons. However, what you eat, as well as how much, can be equally to blame for your bloated belly. For example, gas is also produced in your gut when bacteria acts on partially digested food.

Foods that can cause a bloated belly

  • Starchy foods (including potatoes, noodles and corn)
  • Cruciferous vegetables (commonly broccoli and Brussels sprouts)
  • High fibre foods that absorb water in the gut (for example, beans, fruit and peas)
  • Some artificial sweeteners (polyols)
  • Garlic, onions and leeks

Menstrual cycle

Oestrogen has a big role in deciding how women retain water. Oestrogen levels fluctuate during a woman’s monthly cycle, with the body typically retaining more water when oestrogen levels are higher in the week or so leading up to the start of a period. As a result, a common symptom of premenstrual syndrome (PMS) is bloating.

Food intolerances and allergies

If your body has difficulty digesting certain food types (such as gluten and lactose) it can lead to bloating.

Digestive conditions

When there’s an imbalance in the gut, it can lead to more gas being produced, which can cause abdominal bloating. This can be due to anything from an acute stomach bug or bout of constipation, to more long-term digestive conditions such as coeliac disease and irritable bowel syndrome.

Summary: What is your bloated belly telling you?

A bloated stomach is due to some kind of imbalance in your gut. This can be due to anything from what you ate for your last meal, to hormones. Or even disproportionate air intake due to over-zealous gum chewing or consuming fizzy drinks. The secret to beating the bloat is recognising any patterns in fluctuations in the swelling around your waist. So, the old adage ‘listen to your gut’, is literal logic when it comes to working out what’s triggering your stomach bloating. And if bloating is new or persistent, it’s always worth seeking opinion from your GP.

Last updated: 15 June 2020

ConditionsDigestive Health