Understanding Bloating: Causes and Solutions

What is Bloating?

Bloating means your belly feels swollen, full, or uncomfortable. Sometimes, your stomach actually looks bigger (this is called distension). But in many cases, you just feel it, even if it doesn’t show.

Bloating is actually quite common; in a US survey, more than 31% of people reported functional bloating (1, 2, 3). Interestingly, the majority of people with IBS also experience bloating (4, 5, 6, 780324-9/fulltext)).

Types of Bloating

It helps to know which type you might have, so you can address it better:

• Gas-bloating: Feeling like there’s trapped air or lots of burps/farts.

• Distension-bloating: Your tummy actually expands and looks larger.

• Constipation-related bloating: When stool builds up in the colon, it can slow gut movement and stretch the intestinal walls, leading to gas retention and bloating.

• Food intolerance bloating: After eating certain foods, you feel uneasy or too heavy.

  
  

• IBS-related bloating: People with Irritable Bowel Syndrome often feel bloated even with normal gas levels because of irregular gut motility and gut-brain signalling.

• SIBO-related bloating: Small Intestinal Bacterial Overgrowth causes bacteria to ferment food too early, creating excess gas, discomfort, and a tight upper belly soon after meals.

• Visceral hypersensitivity bloating: In some people, nerves in the gut are extra sensitive. Even small amounts of gas feel painful or “balloon-like,” common in functional gut disorders.

• Functional bloating: When no specific cause is found, yet bloating persists due to stress, altered gut-brain axis, or eating habits.

• Dysbiosis in the Gut: Research shows that when certain gut bacteria ferment food too quickly, it increases gas and bloating. People who produce less methane (a gas that can slow digestion) sometimes feel more bloated after eating foods high in fibre or sorbitol.

  
  

In people with IBS, studies have found that the ratio of two key bacterial groups, Firmicutes and Bacteroidetes, often shifts. This imbalance can affect gut movement and sensitivity, making the belly feel swollen or tight even without visible gas buildup.

In short, a disturbed gut microbiome can make your digestive system overreact, leading to bloating, discomfort, or visible distention after meals.

(References: *Collins et al., Ringel-Kulka et al., Gut Microbiota and IBS studies

Rome III Criteria for Functional Bloating

According to the Rome III Criteria, functional bloating is diagnosed when:

• There is a recurrent feeling of bloating or visible abdominal distention for at least 3 days per month.

• The onset of symptoms began at least 6 months before diagnosis.

• Symptoms have been present for at least 3 months.

• The individual does not meet the criteria for other functional gastrointestinal disorders such as IBS or functional dyspepsia.

  
  

(Reference: *Rome Foundation, Rome III Diagnostic Criteria for Functional Gastrointestinal Disorders

What is the Main Cause of Bloating?

Here are the big reasons (some simple, some more complex):

• Swallowed air (aerophagia): Eating too fast, chewing gum, drinking from a straw, and talking while eating can lead to swallowing air, which can cause burps and belly pressure (8).

  
  

• Gas from digestion: Some foods are hard to digest. They go to the large intestine, where bacteria break them down and release gas. Foods with certain carbs (FODMAPs) are the main culprits (9, 10, 11, 12).

  
  

• Slowed gut movement/constipation: When food or stool stays longer, things ferment, gas builds up, and your belly may distend.

  
  

• Food intolerances or malabsorption: For example, if you’re lactose intolerant, dairy may cause bloating, gas, and discomfort.

  
  

• Changes in fibre or diet too quickly: If you suddenly add a lot of fibre (especially fermentable fibre), your gut bacteria produce more gas while adjusting. One study found a 41% increase in bloating when switching to a high-fibre diet in certain conditions.

  
  

• Water retention and other non-gas causes: Sometimes it’s not about gas but fluid retention or even gut stretching in functional disorders.

  
  

How Can You Identify Your Kind of Bloating?

Here’s a checklist:

• Keep a food diary for 1–2 weeks: Write what you eat, when you feel bloated, and how long it lasts.

• Note patterns: Do you always bloat after dairy? Beans? Carbonated drinks?

• Check your stool: Are you constipated or passing stool regularly?

• Check other symptoms: If you have weight loss, blood in stool, fever, or night sweats, that’s a red flag. Consult your doctor immediately.

• Is the swelling visible (distension) or just a feeling? That can hint at functional gut causes vs simple gas.

  
  

How to Reduce Bloating?

Nutrition is not the only answer, but it’s one of the most powerful and easiest to start with. Here’s how to tweak your diet to reduce bloating:

1. Slow Down Eating & Avoid Swallowing Excess Air

• Eat meals slowly and chew well.

• Avoid drinking large fizzy drinks, using a straw, chewing gum, or talking while eating (all increase swallowed air).

• After major meals, try a 10–15 minute walk. One study found this helped reduce bloating. Harvard Health

  
  

2. Gradually Adjust Fiber Intake

• Fibre is good; it helps digestion and prevents constipation. But adding too much too fast can cause gas and bloating.

• When increasing fibre, also increase fluid (water) so things move.

• Prefer whole grains, fruits, and vegetables, but ramp up slowly over a week or two. Many of my clients come to me after suddenly increasing fibre intake, only for it to backfire.

  
  

3. Choose Foods That Help Ease Bloating

Here’s a short list of foods & drinks that research and diets say can help:

• Water-rich veggies (cucumber, celery) help flush excess fluid and assist digestion.

• Yoghurt with probiotics: beneficial bacteria can improve gut health and reduce bloating, especially in IBS.

• Bananas and berries: less likely to cause fermentation problems compared to high-fructose fruits like apples or pears.

• Avoid or limit: fizzy/sugary drinks, large servings of beans/legumes if sensitive, raw onions/garlic if you notice they trigger you.

  
  

4. Drink Enough Water & Limit Salt

• Staying hydrated helps stool move and prevents constipation and gas build-up.

• Too much sodium (salt) can cause fluid retention and make the belly feel puffy. Some studies link salty diets with more bloating. Bloomberg School of Public Health

  
  

5. Move Your Body

• Physical activity helps digestion, moves gas and stool along, and reduces bloating. A simple walk after meals can help. Harvard Health

• Stress also plays a role (gut-brain axis) — so relaxing, breathing, and stretching help too.

  
  

Top Questions Parents & Teens Ask (and Their Answers)

Q: Why do I feel bloated every night, even if I eat ‘clean’?

A: Even clean foods can contain high-FODMAP items (beans, lentils, some veggies), or you may be eating large portions, chewing fast, or have low gut motility.

Q: Does a high-protein or vegan diet cause bloating?

A: Possibly. One trial found that when people switched to a high-fibre diet with a lot of plant proteins (beans, legumes), they had about 40% more bloating compared to a carb-rich version. So if you switch diet type, give your gut time to adjust. Slowly increase new foods.

Q: If I feel bloated, is it serious?

A: Usually, bloating is harmless. But see a doctor if you have blood in stool, unexplained weight loss, persistent pain, vomiting, or night sweats. These could hint at more serious issues.

Q: Can I use over-the-counter pills?

A: Some remedies (e.g., simethicone, lactase tablets for dairy intolerance) exist, but they are not magic. The foundation is diet + movement + identifying triggers.

Summary

Bloating is more common than you think. But you can take steps to reduce it. Nutrition isn’t about “eat less”; it’s about eating smarter for your gut. If symptoms persist, get help from a professional (qualified nutritionist or doctor).