Not including enough fibre in the diet €“ this is the most common cause. Fibre is found in fruit, vegetables, whole grains, cereals and pulses

Not drinking enough €“ liquids add fluid to stools, making them softer and easier to pass

Lack of exercise €“ this is a particular problem for the elderly and anyone who is bedridden or immobile after an accident, illness or surgery, for example

Medication €“ some drugs cause constipation as a side effect. Drugs that can cause problems include painkillers containing codeine, antacids containing aluminium compounds, antispasmodics, antidepressants, diuretics, iron supplements and anti-epileptic medicines

Irritable bowel syndrome (IBS) €“ see the Stomach Pain and Cramps section for more information

Pregnancy €“ many women find that they become constipated as their pregnancy progresses because of hormonal changes and the increase in pressure within the abdomen

Old age €“ unfortunately, as we get older, the movement of the large intestine may start to slow down. This can often lead to chronic constipation

Long-term laxative usage €“ if someone uses laxatives too often, they may stop having the desired effect

Cancer €“ although rare, a cancerous growth within the intestines can cause diarrhoea and/or constipation. It is normally accompanied by unintentional weight loss and blood or mucus in the stools.

The role of dietary fibre

Having an adequate dietary fibre intake can significantly reduce the likelihood of developing constipation. Adults should aim to consume at least 18g of fibre a day by eating plenty of fruit and vegetables, wholegrain starches, oats, nuts and seeds.

Fibre keeps bowel movements regular as it helps food to pass through the digestive system more easily. There are two main types of fibre €“ soluble and insoluble. Both types are essential for the normal functioning of the digestive system. Soluble fibre allows water to be retained in the stools, making them softer and therefore easier to pass. Insoluble fibre adds bulk to faeces, which causes them to pass through the gut more quickly, preventing the uncomfortable feeling of constipation.