It’s fairly common to hear someone say they’re feeling “bloated”. You might even have said it yourself. But what does feeling bloated actually mean?
In general terms, bloating refers to your stomach feeling overly full. You feel as if you have a distended belly, along with uncomfortable symptoms such as burping, gas, swelling and flatulence. You could also have constipation or diarrhoea.
Medically speaking, bloating is a result of an increase in the volume of gas. Dr Chris Kong San Choon, head and senior consultant of gastroenterology and hepatology service at Sengkang General Hospital explains: “Each individual has 100-200cc of gas in the intestinal tract. The volume of gas could be increased by swallowing air (aerophagia), drinking carbonated beverages, or neutralisation of acid or alkali in the gastrointestinal tract.”
In short, there are many reasons you could feel gassy or bloated. Some of them might even surprise you.
Diet and lifestyle causes
What you put into your body is, of course, an extremely important factor in determining how gassy you feel. Jaclyn Reutens, dietitian at Aptima Nutrition & Sports Consultants, lists a few foods that make us feel gassy and explains why:
- Beans contain raffinose, a complex carb that produces methane gas, hydrogen and carbon dioxide when digested by the gut bacteria. This combination can cause gassiness.
- Dairy products contain lactose. Lactose-intolerant individuals do not produce enough lactase so they have difficulty digesting lactose, causing bloating.
- Cruciferous vegetables like broccoli and cauliflower contain FODMAPS such as raffinose that can cause bloating.
- Artificial sweeteners such as xylitol and sorbitol used in sugar-free products contain sugar alcohols, which can lead to bloating and gassiness.
- Onions contain high amounts of fructans which is a known cause of bloating and some individuals are intolerant to other compounds in onions. Onions are a known cause of bloating and digestive discomforts.
- Carbonated drinks contain high amounts of carbon dioxide and you end up swallowing a lot of gas when you drink them. If you are unable to expel the gas, you end up bloated and it can even lead to cramps.
Yes, fibre is good for us but you might be surprised to know that it can cause bloating.
“Having too much fibre in your diet can lead to an overproduction of gas from the gut bacteria trying to break it all down and producing gas as a by-product,” says Jaclyn.
Therefore, don’t overdo your fruits, vegetables and whole grains intake. Eat just enough as “too much of a good thing can end up being bad for you”.
The Health Promotion Board recommends that women get about 20 grams of fibre per day. Some examples of fibre content: 1g in a bowl of cooked white rice, 4g in two teaspoons of baked beans, 3g in one small orange, 2g in a medium slice of papaya, 3g in a small cup of carrots and 6g in a small cup of spinach.
The feeling of getting together with friends or family for a chat over your favourite food is amazing, but it might also be making you more gassy (and nobody wants that). Talk as much as you like if you’re a chatterbox, just don’t do it while eating. While talking a lot per se doesn’t make a difference, eating or drinking and talking at the same time isn’t advised.
Dr Kong reveals: “To talk, a person has to breathe in, and depending on the amount of emotion during talking, there might be a lot of breaths. Thus, as the food or drink is swallowed, air also enters the stomach and then into the intestine, resulting in bloating. This is similar to people who smoke and talk at the same time.”
The explanation for this is similar to eating and talking at the same time – you swallow a lot more air when you eat quickly. This then leads to a buildup of gas in your gastrointestinal tract. It’s best to eat slowly, take smaller bites and chew your food well.
You could also be swallowing more food along with the air. “Eating too fast can lead to eating more food than you need and the sheer volume of food can also cause bloating,” says Jaclyn. “This can be uncomfortable and take hours for your stomach to completely digest your foods.”
She adds that, if you’re prone to bloating, drinking through a straw could exacerbate your bloated feeling as it captures air and increases the amount of gas in your stomach.
If you have an imbalance of bacteria in your intestines because of irritable bowel syndrome (IBS), it may result in excessive production of certain gases. This imbalance is sometimes corrected by the use of probiotics and/or prebiotics, a common treatment used for IBS.
Dr Kong points out that people with functional bowel syndromes – such as IBS – complain of bloating often. “Research has shown that there are approximately 500 species of bacteria in the large intestine alone,” he explains. “The number of bacteria in the intestines is estimated to be more than 10 times the total number of cells in the body.”
Patients with IBS have certain distinctly different microbiome, which leads to the theory that this imbalance of intestine bacteria causes bloating.
There are certain medical conditions – such as diabetes – that slow down the movement of food and faeces through the intestinal tract. Dr Kong explains that the slow transit time builds up faeces (more faeces, more intestinal distension) and also increases the amount of time that fermentation can occur (more fermentation, more gas).
Everyone has a different threshold for pain. In that same way, we may feel a different level of discomfort from bloating for the same volume of gas in our intestine. For example, patients with IBS could be hypersensitive to minimal distension.
“There was a study where patients with functional bowel syndromes and those who were normal (did not have IBS), had a gas bag insufflated in their rectum. Patients with functional bowel syndromes started experiencing pain at lower volumes of insufflation,” Dr Kong says.
Are you on the contraceptive pill? Then there’s a chance you could feel bloated and have other gastrointestinal symptoms more often. If you’re treating irritable bowel syndrome with prebiotics and probiotics, this could cause bloating too.
Dr Kong lists other medications that could lead to bloating: “Commonly used laxatives, like psyllium husk (marketed as Fybogel), may cause bloating. Certain antacids used to treat acid in the stomach/indigestion may also cause bloating. Opioid-based analgesics have also been associated with bloating, partly by causing constipation.”
It’s not just what’s happening to your body physically that could lead to bloating. Dr Kong reveals that stress and anxiety have been shown to increase circulating levels of hormones related to stress. These may trigger a cascade of events in the intestines (e.g. increase intestinal permeability) that result in the development of irritable bowel syndrome (IBS) symptoms.
Also important to note here is the brain-gut axis, which links stress and anxiety to triggering certain gastrointestinal symptoms.
“The common usage in the English language has illustrated this. People who are about to go on stage or about to give a speech have often said they have ‘butterflies in their stomach’. Stress has also triggered gastrointestinal upset, for example, students having diarrhoea or vomiting before exams,” says Dr Kong.
A person who is constipated has more gas in their body. Being constipated means your stools stay in your large intestines (colon) for a longer period of time. The large amount of bacteria in this part of your body causes your faeces to ferment and generate gas. This then leads to your feeling of discomfort.
The best ways to ease constipation are to exercise or increase your fibre intake if you’re not getting enough. You should also drink more water.
“It is hard to pass hard stool,” Dr Kong explains. “Singapore is a hot place where people perspire a lot due to the heat. People may not drink enough water. Locals enjoy coffee and tea, both of which are diuretics, which make people pass urine and get more dehydrated. In a study of 117 people with constipation, the group that had the higher fluid consumption had better bowel movement.”
Certain medicines – such as opioids like codeine and tramadol, hyoscine or buscopan – can cause constipation so take note of any medications you’re on.
When should you see a doctor?
It can be tough to figure out if your frequency and extent of feeling gassy is normal or something to worry about. Dr Kong admits that bloating is common but there are certain signs that should prompt you to seek medical advice.
Watch out for these symptoms:
- Bloating with early satiety (unable to finish the same amount of food as per usual) or loss of appetite
- Difficulty in swallowing food and/or vomiting (especially if there is blood in the vomit)
- Unexplained weight loss (e.g. not due to dieting)
- Bloating that interferes with sleep or daily activities (e.g. too uncomfortable to work/watch TV/ carry out hobbies)
- Change in bowel habit (e.g. constipation or passing motion more frequently)
- Blood and/or mucus in your stools
- If you feel a hard lump (mass/growth) in your abdomen
“If blood tests show anaemia, vitamins/iron deficiencies, or raised inflammatory markers (e.g. c-reactive protein or erythrocyte sedimentation rate), patients should also have further investigations,” he adds.