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Colorectal Cancer : Causes
Western Medicine Chinese Medicine

Prevention and early detection are very important factors in controlling and curing colorectal cancer. Several factors have been identified which play a role in the risk and development of colorectal cancer. They include; age, colorectal polyps, diet, family history, genetics (heredity), and inflamatory bowel disease.

Colorectal cancer occurs most frequently after the age of 50. The average age at diagnosis is 60-65. The risk of colorectal cancer increases after the age of 40 and up to the eight or ninth decade of life.

Colorectal Polyps

Polyps in the colon

The presence of colorectal polyps can increase the risk for colorectal cancer. Polyps are benign growths in the colon and rectum but they can become cancerous over time. Approximately 30% of people in their 50's develop polyps; the occurrence of polyps increases to about 50% in people in their 70's. Not all polyps will become cancerous only about 5% of all polyps will become cancerous. It can take 5-10 years for a polyp to become cancerous.

The incidence of colorectal cancer is highest in countries where meat is a major part of the diet and fruits, vegetables and fiber are a small part of the diet. The Western diet is high in animal fats and low in fiber. Diets in underdeveloped countries tend to be rich in fibers from fruits, vegetables and grains, and low in fat. Studies have shown that meat and fat consumption increase the risk of colorectal cancer. It is thought that dietary fats produce cancer-causing substances when they are digested.

Family History and Genetics
Having a first-degree relative (parent, sibling, or child) has been shown to increase one's risk of colorectal cancer 2-4 fold. There are other genetic conditions that are associated with an increased risk for colorectal cancer. They include familial adenomatous polyposis (FAP) and Garner's Syndrome which are inherited conditions. Patients with these conditions develop hundreds of polyps in their colon and rectum. The polyps can become cancerous and persons affected with these conditions have nearly a 100% risk of developing colorectal cancer if left untreated.

Inflammatory Bowel Disease
Ulcerative colitis is a condition associated with an increased incidence of colorectal cancer. Patients who have ulcerative colitis have a 30-fold increase in risk. The duration of disease appears to be linked with the increased risk for colorectal cancer. Patients have a 3% increase in risk of developing colorectal cancer after 10 years of active disease and the risk increases to over 30% with 30 years of active disease.


Click here to see the causes of colorectal cancer from a TCM perspective.

According to TCM, formation of cancer is generally due to the depletion of disease preventing factors and yin-yang disharmony of the body, which can result in different types of pathological phenomena, such as qi stagnation, blood stasis, phlegm condensation, toxic heat accumulation, and dampness collection. These morbid conditions interact with each other and cancer may form when they further interact with external pathogenic factors.

The usual causative factors are as follows:

Improper Diet
TCM takes food very seriously and regards the middle burner (body region where the spleen and stomach are located) as the area for digestion. The digestive organs are vulnerable to inappropriate and unbalanced dietary habits, for example, excessive eating, greasy diet, over consumption of alcohol, and unclean foods. When the transportation and transformation processes are affected, undigested foods remain too long in the region and brew into dampness and heat evils. These evils accumulate and infuse downward into the large intestine, causing qi stagnation, and blood stasis in the intestines. The dampness, heat, stasis, and toxic materials all blend together and may cause cancer over time.

Emotional Problems
Extreme emotional conditions like pensiveness and anxiety leads to under-functioning of the liver and affects the movement of qi (vital energy) mainly, causing the formation of internal pathogenic factors such as dampness and phlegm. When these evils further stagnate, they transform into toxic heat evils, which then infuse downward and invade the intestines. This gives rise to qi stagnation and blood stasis in the intestines. Cancer may occur after a long period if the condition persists.

Uncontrolled Chronic Dysentery or Diarrhea
Persistent diarrhea leads to depletion of qi (vital energy) in the body which affects the spleen. In TCM, when the spleen cannot perform its transportation and transformation functions to send the pure nutrient essence upward to the heart and lungs where it is transformed into qi and blood for body nourishment, qi (vital energy) movement becomes abnormal and results in a morbid state. Impure substances or retention of phlegm and static fluid then build up. When this condition lasts for long periods, the internal equilibrium is disturbed, and cancer can easily form.