A common cause of constipation is inadequate fibre in the diet. Fibre is required to give bulk to the faeces. When we eat too little fibre, the faeces are small and do not stimulate the muscles of the colon to contract properly to propel them through the colon and rectum. The delayed passage of faeces through the colon means there is more time for water to be extracted from them, resulting in small, hard and dry faeces which may be hard to pass. The same thing can happen if we have too little fluid in our diet.
Another common cause of constipation is not heeding nature’s call for us to empty our bowels. We should empty our bowels when we feel the need to. Obviously it is not always convenient to do this and no harm will occur if we occasionally do not answer nature’s call to empty the bowel. However, if we keep on putting it off it can lead to the loss of normal bowel reflexes. As a result the bowel becomes sluggish and we lose the sensation of wanting to empty the bowel. Painful conditions affecting the anus and rectum, such as piles and fissures, can cause constipation by inhibiting defecation; constipation makes these conditions worse.
Constipation can also arise from the other conditions which disrupt the normal activity of the muscles in the colon and hence slow the passage of faeces through the colon. Lack of exercise can do this as can some medicines prescribed by your doctor or bought over the counter. These include some painkillers, antidepressants, iron-containing tonics and some antacids used to treat indigestion and heartburn.
Some medical problems such as diabetes, hypothyroidism, irritable bowel syndrome, diverticulitis, neuropathy, megacolon and depression can give rise to constipation. Constipation may also be the first symptom of tumours within the bowel. |
