Constipation is a condition where the bowel movements are being restrained making the passage throughout the tract very hard. Defecation in this situation is painful and infrequent. Generally constipation is due to certain lifestyle factors such as: low fiber intake, low fluid (or water) intake, lack of exercise, and side effects of medication (at some degree).
The main organ system that is affected by constipation is the digestive system. Considering the stool chart, constipated people often have dry structure due to lack of fluid which makes it hard to pass in the rectum. Loss of fluid in the fecal matter can make it hard thus it can injure the linings of our intestines and rectum thus making it very painful upon defecation. The harder the fecal matter, the longer it will take to be excreted thus increasing the chance of toxicity and other complications.