Most of us have experienced the feeling of being bloated, when your tummy is stretched, puffy and uncomfortable. It often happens after a big weekend, involving lots of eating and drinking, or over a festive season. But for some people, bloating is more than an occasional inconvenience.

Causes of Bloating

There are several possible explanations for bloating and wind but the usual cause of bloating is gas. Gas can be trapped in the body to cause bloating, or can be expelled from the back passage as wind (flatulence). Bloating is also a common symptom of Irritable Bowel Syndrome (IBS).

It is normal to have gas in your intestine and we all produce several litres of gas a day through the normal processes of digestion. Some of this is reabsorbed into the bloodstream and eventually breathed out, with the remainder being expelled as wind.

One possible cause of excess gas may be swallowing too much air when eating, drinking or talking (aerophagia). Certain foods and fizzy drinks can also contribute to this. Smoking can also make you swallow more air and some people also swallow air as a nervous reaction.

Excess gas can also be caused by bacteria in the colon producing too much gas when it breaks down food. Foods containing complex carbohydrates, for example vegetables such as beans, cabbages and Brussel sprouts, are difficult for the human body to digest and are broken down by gas-producing bacteria instead. Foods that contain sorbitol, an artificial sweetener, can lead to similar problems.

Lactose intolerance (difficulties with digesting lactose - a sugar found in milk) can also cause an excessive amount of gas and bloating. You may become lactose intolerant if you lack the enzyme lactase, meaning that you cannot break down the lactose. Instead, the lactose is fermented by the gas-producing bacteria in the colon.

Tips on reducing excess gas.

There is no simple solution - what works for one person may not work for another – but some people find these tips helpful:

  • Cut down on foods known to cause wind and bloating, such as beans, onions, broccoli, cabbage, sprouts and cauliflower but make sure you still eat five portions of fruit and vegetables a day. Try avoiding high fat foods and eggs – these can produce bad smelling gas – and refined and sugary foods, especially those containing the artificial sweetener sorbitol. Keep hot spicy food to a minimum, particularly if you are not used to it.
  • If you get constipation, take steps to prevent it with a fibre-rich diet, drinking lots of fluids and taking regular exercise. Even a 20-30 minute brisk walk four times a week can improve your bowel function.
  • Try not to swallow too much air. Don’t talk and eat at the same time, sit down to eat (sitting upright and not slumped over), reduce the amount of fizzy drinks you consume, stop chewing gum and chew with your mouth closed so that you’re not taking in excess air.
  • Think about the way you eat and create a relaxed environment when eating, as nervous tension at meal times can affect digestion. Eat small, regular meals (perhaps 5-6 a day) so that your bowels are fuller, as an empty bowel produces more wind.
  • Some people find that eating a large meal late at night makes them feel bloated and uncomfortable. If you find this is the case, try eating your main meal earlier in the day.
  • If you are having a problem identifying which foods are causing bloating and wind, it can be helpful to keep a food diary for a week or two. Note down everything you eat and drink and how it makes you feel. It may be worth experimenting by cutting out certain foods for a short period (4-6 weeks) to see this if this helps.
  • Drink plenty of water, ideally 1.2 litres a day or more (about 6 to 8 glasses) and avoid caffeine in coffee, tea and cola. Avoid fizzy carbonated drinks because these contain gas and keep alcohol to a minimum as alcoholic drinks can also increase the amount of gas produced. Avoid drinking from a straw as this can make you swallow air.
  • Avoid sitting for long periods. If sitting at work, take regular breaks (at least every hour) to stretch the legs and abdomen.
  • Try to take regular exercise to help improve your digestion - for example, it may help to go for a short walk after eating in order to move gas around. Gently, but firmly, massage the abdomen from right to left to release any trapped wind.
  • People with irritable bowel syndrome (IBS) often complain of bloating, especially in the evening. Peppermint tea or capsules can help ease the bloating associated with IBS.

Persistent Bloating

If you have persistent bloating that does not alter in size, or other symptoms such as weight loss, a change in your normal bowel habit, abdominal pain, severe fatigue or bleeding from the back passage always seek medical advice.