What causes constipation?

There are many causes of constipation but the main cause is due to the slow movement of the stools through the bowel. The large bowel absorbs water from the stools when they are not moved regularly and this can result in small or hard, dry stools that are difficult to pass. A number of factors can cause the passage of stools to slow down. The most common causes are:

Inadequate fluid intake or dehydration

Water makes the bowel motion soft and easier to pass. With insufficient fluid intake, the stools become hard and dry which makes having a bowel movement difficult. 

Inadequate amounts of fibre in the diet 

Regular consumption of fibre rich foods like fruit and vegetables, cereals, bran and whole grain bread help to maintain a regular routine. The body does not absorb fibre so it travels through the system to the bowel, where it provides bulk for the bowel motion. Fibre also absorbs water, making the motion soft and easier to pass.

Ignoring the urge to have a bowel movement 

This is especially common in children as they may be too busy playing to take the time to go to the toilet or accessing a toilet may be difficult. Busy schedules and racing to be ready for school or work can result in delaying a trip to the toilet. 

Lack of physical activity

Exercise helps the muscles work to move the stools waste through the bowel. 

Irritable bowel syndrome (IBS) 

Find out more about IBS on the Mintec page.

Change in lifestyle or routine such as travel 

When the normal body clock is disrupted by travel, routine bowel habits can be upset and constipation may result. 

Pregnancy

Female hormones can affect the bowel habit and constipation is more common during pregnancy. 

Abuse of certain types of laxatives

Some laxatives and inappropriate use of laxatives (eg. for weight loss) may cause the bowel to become dependent. 

Medications

Constipation can also be caused by some medications and certain medical conditions. Prescription medicines used to treat blood pressure, heart disease and depression can cause constipation. Some over the counter products such as analgesics which contain codeine as well as iron supplements and some antacids are also known to cause constipation. If you have any concerns you should talk to your doctor or pharmacist.