The human digestive system starts from mouth and extend along esophagus, stomach, small intestines, large intestines to finally terminate in rectum. Rectum is the final portion of digestive tract that opens into the anal canal. In adults the rectum is approximately 18-20cm in length and is conveniently divided into three equal parts the upper-third, which is mobile and has peritoneum cover, middle third is present within the bony pelvis and is the widest part of the rectum and the lower third which lies within the muscular floor of the pelvis. What is the function of rectum in the digestive system? What diseases could happen to rectum? How to prevent rectum cancer?

Rectum Function

As being the last part of the digestive tract, the rectum acts as a temporary storage facility for feces / waste material. The food we eat undergoes the process of digestion once we start chewing it in our mouth then it is passed on to stomach, small intestines and finally large intestine, the remaining residue of undigested food with bacteria and the juices from the digestive system enter the rectum in the form of feces. These feces remain in rectum until we proceed with defecation in which through bowel movement they are transferred to anal canal and then outside of the body.

How does It Work?

Defecation is the final act of digestion, normal human beings defecates from a few times a day to few times/ week. Before defecation all the waste material/feces is transported to rectum. Here rectum acts as a temporary storage site for the waste material coming as a result of digestion. The filling of feces put pressure on the walls of rectum thus stretching the walls of rectum and stimulating the stretch receptors of nervous system present in the rectal wall resulting in “defecation reflux”. Defecation reflex is the urge to defecate produced after the stimulation of the nerves. This urge to defecate arises from the reflex contraction of rectal muscles, relaxation of the internal anal sphincter, and an initial contraction of the skeletal muscle of the external anal sphincter.

If not acted upon this urge the feces in the rectum get hardened because of the absorption of fluids which leads to constipation.

Ailments Related to Rectum

Rectal diseases are common and serious and can occur at any age and they hinder rectum function. Inflammation is more common in young age while tumors in elderly. Symptoms that need to be attended by the doctor include bleeding per rectum, altered bowel movement, mucus/pus discharge, tenesmus and prolapse. Common rectal diseases are hemorrhoids, rectal injuries, rectal inflammation (proctitis), rectal prolapse and rectal cancer.

1. Hemorrhoids

The rectum and anal canal are richly supplied with veins, these can get swollen and inflamed due to irregular bowel movements like due to constipation or diarrhea, these inflamed veins are called hemorrhoids. They are very painful, and do bleed. Symptoms include blood in stools, pain while defecation. More than 50 % of Americans population will get affected by hemorrhoids by the age of 50. Consult your doctor if you are experiencing any of these symptoms.

Prevention of hemorrhoids usually includes higher use of quality fiber diet, avoid constipation or diarrhea.

2. Proctitis

Proctitis is the inflammation of rectum. It can be acute or chronic with symptoms like tenesmus, passage of blood and mucus and in severe cases of pus also. The inflammation of rectum is usually due to some other underline disease or infection relating the digestive system. To avoid any such condition, maintain a healthy clean diet and increase the intake of fibers.

3. Rectal Cancer

Colorectal cancer is the fourth most common variety of malignant tumor found in women, and most common cancer in males. Overall it is the second most common cancer in Western countries. The rectum is the common site. The symptoms of cancer are also the same as other rectal problems like bleeding (bright red), abdominal pain, small and narrow stools, altered bowel habits, constipation or diarrhea or sense of incomplete defecation. If any of these symptoms appear consult your doctor immediately.

Prevention of Rectal Cancer

Prevention of rectal cancer includes regular screening especially with people at risk, such as those with family history of colorectal cancer or after the age of 50. Also significant changes in lifestyle like diet modification, exercise, avoid smoking and alcohol can also help significantly in reducing the risk and to improve rectum functions.

1. Get Screened

People with risk of developing colorectal cancer include people more than the age of 50 or people with family histories, but other should also get screened if they have any of above mentioned or their doctor suggests as so. The screening includes include colonoscopy, sigmoidoscopy, and fecal occult blood testing.

2. Eat Wisely

A person should maintain a healthy diet. Healthy diet is the one with adequate amount of minerals and dietary fibers. A person should eat more fruits and vegetables as they contain vitamins, minerals, and antioxidants, which may play a role in cancer prevention. Fruits and vegetables are also source for dietary fiber, dietary fibers play an important role in the digestion of food and bowel movement.

3. Exercise

A sedentary life increases the risk of colorectal cancer but if person continues to do exercise daily the risk is decreased by 25%, a person should at least perform exercise for 30 minutes.

4. Avoid Smoking and Drinking

Smoking is injurious to health this is well known fact, it not only increases the risk of mouth and lung cancer but also the risk of rectal cancer by 18 %, that’s why one should give the habit of smoking as soon as possible

5. Keep a Healthy Weight

Obesity is also linked with colorectal cancer especially in men according to some studies the belly fat increases the risk of developing cancer. So one should maintain ideal weight and maintain healthy diet with daily exercise

6. Drink Green Tea

Use of green tea according to some researches is also very beneficial in preventing colorectal cancer but other types of cancers too. A study published in 2011 of Chinese men found a 54% lower incidence of colorectal cancer in those who regularly drank green tea. But researchers still continue to work on finding out uses of this magical Chinese herb.