Healthy Digestive System: Misconceptions about Bloating and Gas

BLOATING is one of the most common and bothersome experiences. In tThis article, I by Datin Dr Sharmila Sachithanandan, a Consultant Gastroenterologist at Subang Jaya Medical Centre (SJMC) will discuss talk about the various causes of bloating, how to tell if your bloating is abnormal and how to maintain a healthy digestive system. It will also touch on food intolerances and a frequent question doctors get, which is whether probiotics will help.

Bloating is a sensation of your stomach feeling tight and full of air. Your clothes or belt suddenly feel tight after a meal or you may feel the inability to pass wind in either direction. Belching, or flatus, becomes uncomfortable and even painful for some people.

Our local term of “angin” is commonly used to describe a whole plethora of symptoms but usually it is that feeling of “trapped air”. Essentially, your gastrointestinal tract is filled with gas.

Bloating affects 10% to 30% of the general population and in some cases, will have an impact limiting their daily activities. Bloating usually suggests the presence of excessive gas, but occasionally, it can be due to fluid (ascites), which is more worrying.

Is it bloating the same as indigestion?

Bloating, like heartburn, constipation, and diarrhoea, is a common feature of indigestion. Indigestion means improper digestion of food. This could be due to several reasons ranging from infection to acid reflux and motility disorders, causing food to not be broken down and absorbed properly. Some common reasons are discussed below:


One of the most common causes of bloating is constipation. Constipation is the difficulty in passing stool. Typically, you pass stools less than three times a week, the stools take the form of hard, dry pebbles, you struggle to push it out and feel pain or feel an incomplete evacuation.

Stool stored in your rectum and colon is old food that is being broken down and it releases gas, which builds up and goes back into your upper gut, causing the bloated feeling. This backward flow of gas can also exacerbate acid reflux, giving rise to heartburn.

The longer stool stays in the colon, the more water is reabsorbed and the more difficult the stool becomes to evacuate. It is a good habit to look at your stool before flushing it down. The presence of blood is not normal.


Gastroparesis is slow gastric emptying or gastric paralysis. Certain medical conditions such as diabetes, hypothyroidism and Parkinson’s disease cause the gut to move slower than normal.


Aero (air) phagia (eat) is a condition where there is excessive swallowing or gulping of air. This is occasionally seen in children and adults and is associated with an underlying psychological disorder such as anxiety or depression.

Food intolerance

Food intolerance is the inability to digest certain foods (as opposed to food allergies where the immune system reacts to the food). Intolerance to food items such as lactose, gluten and sugar alcohols (zero calorie alternatives to sugar) can cause bloating and abdominal discomfort.

Fermentable oligo-di-mono-saccharides and polyols, or Fodmaps, are a group of short-chain carbohydrates found naturally in many foods. Examples of Fodmaps are fructose, bread, honey, soft cheese, beer and apples. Fodmaps may be poorly digested by some people. Fermentation of the undigested carbohydrates releases gas and causes bloating and discomfort. This is very commonly seen in association with people with irritable bowel syndrome (IBS).


IBS is a functional gastrointestinal (GI) disorder characterised by abdominal pain and altered bowel habit in the absence of a specific and unique organic pathology, although microscopic inflammation has been documented in some patients. It is a benign disorder that does not lead to cancer. Symptoms, however, can be severe enough to interfere with normal daily activities and affect quality of life.

Bloating is a very common symptom reported by patients with IBS. Up to 30% feel the pain is intrusive. Bloating may result from bacterial fermentation of undigested food, retarded gas transit, increased sensitivity of gut to normal luminal gas volumes or dysfunctional gut muscle wall.

Bloating associated with IBS is seen more in women than men and may be related to the menstrual cycle, as well as commonly seen in constipation-related IBS. Stress, anxiety, depression and fibromyalgia are all interlinked with IBS.

When is it bloating abnormal and how to differentiate?

It is normal to feel bloated occasionally. If this occurs frequently, causes discomfort, interferes with daily activities and sleep, then it is a problem. Passing too much flatus and burping or belching continuously to the point it is embarrassing should tell you it is time to see a doctor.

If at any point you are losing weight without trying, experience a change in your normal stool pattern, notice there is blood, lose your appetite and cannot sleep because of pain or discomfort – please see your doctor immediately.

Misconceptions about bloating

Bloating or abdominal distension is a very subjective symptom depending on an individual’s threshold for discomfort.

Bloating means different things to different people, so the doctor must take detailed history of the patient and perform a clinical examination. Often, minor dietary modifications and monitoring the consistency of stool will suffice.

However, not all bloating is due to food and stool. You may need to see a doctor if symptoms are frequent, persistent or interfering with your daily activities or sleep. Any of the worrying symptoms described earlier should prompt your visit to the doctor. Remember, not all bloating is due to air. It could be fluid (ascites), which is very worrying.

Another frequently asked question is, “Can probiotics help?” The gut is filled with trillions of bacteria. This microbiome is responsible for maintaining our gut health. Everyone’s microbiome is different. What we know is that the more diverse the bacteria, the better protection we get.

The role of probiotics in managing bloating

Some bacteria help to fight disease while some promote diseases. It may also be the reason some people are overweight. The route we were born (vaginal or caesarean delivery), the environment we grew up in, frequent use of antibiotics and stress all affect our microbiome.

When this microbiome is thrown out of balance, food is not digested properly and this can lead to bloating. Manipulating the gut flora is complex. Taking probiotics after certain situations such as acute gastroenteritis, antibiotic therapy and certain chronic illnesses such as IBS can help. However, there is no firm evidence that taking them on a regular basis is beneficial. In some severely immunocompromised patients, probiotics may be dangerous.

Advice for a healthy digestive system

The gut embryo originates from the endoderm, so what is inside matters on the outside, and vice versa. The skin and gut share the same origin and hence they are both windows to each other’s health. Some diseases of the gut manifest as skin problems such as eczema, psoriasis and allergies.

The gut has been called the second brain because it has so may nerve connections. In the last 20 years, a plethora of research has shown that the GI tract is more than a long food pipe. Gut health has been linked to sleep quality, mental health, skin conditions, obesity, diabetes, autoimmune conditions and even cancer. We should do our best to maintain a healthy gut by watching what goes in and what comes out.

Try to reduce the stressors, maintain regular and sufficient sleeping hours, chew your food properly and do not rush through your meals, drink water, and watch your diet. Simple elimination of certain foods can help. Avoid highly processed food, animal fats and refined sugar, and make sure you pass stool well.

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