The Causes

Age

The older a person is, the higher their chances are of getting colorectal cancer. Though young people may be diagnosed with colorectal cancer, about 90% of the diagnosed cases are 50 years or older. When a person is 50 years or older, their chances of being diagnosed are about 25%; the average age for diagnosis, though, is 64.

Alcohol

Studies based on the relation between alcohol and colorectal cancer have been varied and the results of different forms of alcohol have also varied. The most common results, though, are as follows:

• Beer - unknown affect. Though numerous studies have been done, the results have usually had too much variation to form a conclusion.
• Spirits - researchers at Stony Brook University found that a person can triple their chances of colorectal cancer if they drink nine or more glasses per week.
• Wine - once again studied by researchers at Stony Brook University, it was found that by drinking one to two glasses per week would cut your chances of being diagnosed by 60%.

 Smoking

As well as adding carcinogens to the body, the tobacco from smoking may increase the size of the polyp - the larger a polyp is the likelier that it will become malignant.

Environment

A lack of sunlight has been found to increase the chance of cancerous polyp growth. As well, statistics have shown that colorectal cancer rates are lowest in Kuwait, India, and Romania and highest in America, Switzerland, and Canada. The reason for this, though, is unknown.

Hereditary

First degree relatives (parents, sibllings, children) who were diagnosed when they were younger than 50-years-old increases you risk of cancer. When a person has two or more first degree relatives who have been diagnosed their risk is three times greater. As well, if a person has inherited a genetic mutation called adenoatous polyposis (FAP) their chance of diagnosis by 50 is 93% while those with attenuated FAP have an 80-100% chance of diagnosis.

 Gender

Males who are 65+ are more likely to be diagnosed than females of the same age. At the same time, female smokers are more likely to be diagnosed compared to male smokers.

Diabetes

People who are diabetic have a:

• 20-40% greater chance of diagnosis
• 42% lower chance of survival
• 21% greater chance of a recurrence

Other Causes:

• Past polyp, cancer, or inflammatory bowel disease cases
• Exercising reduces risk by 40%
• Obesity, espcially around the thighs or hips
• Chemical exposure, especially to chlorine and asbestos