It is said online that constipation can cause colorectal cancer. Is this true?

When it comes to constipation, many people have this unspeakable secret. The saying that "long-term constipation can lead to rectal cancer" circulating on the Internet inevitably makes people feel worried. Can long-term constipation really lead to rectal cancer?

Long-term constipation is not a high-risk factor for colorectal cancer

Rectal cancer is one of the most common malignant tumors of the digestive tract. The rectum refers to a section of the digestive tract that is 12 to 15 centimeters long and is located inside the anus. Although it is less than the length of a chopstick, its incidence rate is second only to gastric cancer and esophageal cancer.

Constipation refers to the general term for symptoms such as less than 3 bowel movements per week, reduced stool volume, dry stools, and difficulty in defecation. Strictly speaking, it is not a disease itself, but a clinical symptom.

Studies have shown that compared with people who are not constipated, the incidence of rectal cancer in people with long-term constipation is not higher, and constipation is not a high-risk factor for rectal cancer.

However, constipation is one of the clinical manifestations of rectal cancer. After rectal cancer, as the disease progresses, patients will experience difficulty in defecation or changes in bowel habits: more frequent bowel movements, alternating diarrhea and constipation; changes in stool characteristics, such as thinner, flatter or grooved shapes, or mucus or even bloody stools; labored defecation, with a sense of defecation but no stool. Among them, blood in the stool, increased frequency of bowel movements, and thinner stools are common symptoms of rectal cancer.

In addition, patients with rectal cancer may also experience abdominal pain, which may be persistent dull pain, or radiate to the anus, or may only manifest as abdominal discomfort or bloating. In addition, patients may also feel a mass in the abdomen, and may also experience systemic symptoms such as fever, anemia, weight loss, fatigue, etc.

Although long-term constipation itself does not cause rectal cancer, it may be the intestines' cry for help. If there is a persistent change in bowel habits, constipation, or abnormal stool color, you need to see a doctor in time.

More than 80% of colorectal cancers evolve from adenomas.

Studies have shown that the risk of colorectal cancer in people whose first-degree relatives have colorectal cancer is 1.76 times that of the general population, and the effect of family history on the risk of colorectal cancer is also affected by the number of relatives with the disease. Clinically, more than 80% of colorectal cancers evolve from adenomas, and colorectal cancer usually takes 5 to 10 years to develop from adenoma hyperplasia to the late stage. Therefore, if an adenoma is found during examination, it is recommended to remove it. In addition, the onset of inflammatory bowel disease is related to chronic inflammation of the intestinal mucosa. As the course of the disease prolongs, the patient's risk of cancer increases.

Colorectal cancer "prefers" people with bad living habits

People who consume red meat and processed meat for a long time may be at high risk of colorectal cancer. Studies have shown that for every 100 grams of red meat consumed per day, the risk of colorectal cancer increases by 12%; for every 50 grams of processed meat consumed per day, the risk of colorectal cancer increases by 16%.

In addition, people with diabetes, obesity, smoking, and heavy drinking are also at high risk of colorectal cancer. The risk of tumors in people with diabetes is 3 to 4 times that of non-diabetic people, because the large amount of glucose in the body of diabetics just gives tumor cells sufficient nutrition, allowing them to grow wantonly. Increased insulin levels in obese people promote cell growth and inhibit cell apoptosis, which is related to an increased risk of colorectal cancer; obesity can also stimulate inflammatory responses and promote the development of colorectal cancer. People who smoke for a long time are also at a higher risk of colorectal cancer than non-smokers, and the risk increases with the number of years of smoking and the number of cigarettes smoked. People who drink a lot of alcohol will ingest too many harmful substances during the long-term drinking process, which will cause damage to the intestinal mucosa, thereby affecting the normal function of the intestines and inducing colorectal cancer.

To prevent rectal cancer, we must do "four things"

An unhealthy lifestyle is the "culprit" of colorectal cancer. We need to cultivate a healthy lifestyle in our daily lives. We should adhere to physical exercise, such as running, brisk walking and other aerobic exercises, to increase our resistance and avoid obesity; adhere to a healthy diet, increase the intake of dietary fiber, whole grains, and dairy products, avoid high-fat diets, promote intestinal peristalsis, and maintain smooth bowel movements; adhere to quitting smoking and limiting alcohol consumption to avoid long-term inflammatory stimulation of the digestive tract; adhere to regular physical examinations and participate in early screening for colorectal cancer. High-risk groups need to undergo further diagnostic colonoscopy.

People at general risk can undergo colorectal cancer risk assessment starting at the age of 40; people at medium and low risk can undergo colorectal cancer screening between the ages of 50 and 75; people at high risk can undergo colorectal cancer screening between the ages of 40 and 75. If one or more first-degree relatives have colorectal cancer, the recommended starting age for colorectal cancer screening is 40 years old, or 10 years earlier than the youngest first-degree relative; the screening start and end ages for people at high risk of hereditary colorectal cancer should be earlier, and screening should continue throughout life.

(The author is an associate chief physician, registered nutritionist, health manager, and Healthy China Action speaker)