Colon Cancer: Warning Signs and Screening

Colon cancer, also called colorectal or bowel cancer, affects the large intestine and rectum. It usually begins as a small, harmless growth called a polyp that can slowly turn cancerous over many years. Because it often causes no symptoms in the early stages, many people in Bangladesh are diagnosed late, when treatment is harder. Yet this is one of the most preventable and treatable cancers when polyps are removed early or the cancer is caught in time. Knowing the warning signs and the value of screening can truly save your life.

What are the warning signs of colon cancer?

Colon cancer can be silent at first, so any of these symptoms, especially if they last more than a couple of weeks, deserve a doctor's attention:

• Blood in the stool, either bright red or dark and tarry.
• A lasting change in bowel habits, such as new constipation, diarrhoea or thin, narrow stools.
• A feeling that the bowel does not empty completely.
• Persistent abdominal cramps, bloating or discomfort.
• Unexplained weight loss and constant tiredness.
• Low blood (anaemia) found on a blood test without an obvious cause.

Bleeding is often blamed on piles (haemorrhoids), and while piles are common, you should never assume that is the cause without a proper check, because the symptoms can overlap.

Who is at higher risk?

Risk rises with age, and most cases occur after fifty, though younger people can be affected too. Other risk factors include a family history of colon cancer or polyps, long-standing inflammatory bowel disease, type 2 diabetes, obesity, smoking and heavy alcohol use. A diet high in red and processed meat and low in fibre, fruit and vegetables also increases risk, as does a largely inactive lifestyle.

How does screening help?

Screening means testing for cancer before any symptoms appear, and it is powerful because it can find and remove polyps before they ever turn cancerous. A colonoscopy lets a doctor look directly inside the bowel and remove polyps in the same session. A simpler stool test that checks for hidden blood is also used and can be repeated regularly. People at average risk are usually advised to begin screening around the age of fifty, while those with a family history or other risk factors may need to start earlier. Your doctor can advise the right test and timing for you.

How can you lower your risk through diet and lifestyle?

Everyday habits make a real difference to bowel health. A few changes go a long way:

• Eat plenty of fibre from vegetables, fruit, brown rice, oats, lentils and whole grains.
• Limit red meat and avoid processed meats; choose fish, chicken and pulses more often.
• Stay physically active with regular walking or other exercise.
• Keep a healthy weight and manage diabetes well.
• Stop smoking and limit alcohol.
• Drink enough water to support healthy digestion.

When should you see a doctor?

See a doctor promptly if you notice blood in your stool, a change in bowel habits lasting more than two weeks, ongoing abdominal pain, or unexplained weight loss or tiredness, even if you think it is just piles. Seek urgent care for heavy rectal bleeding, severe abdominal pain, or vomiting with a swollen, painful belly, which can signal a blockage. Early assessment, and screening if you are over fifty or have a family history, offers the best chance of a cure. You can find a gastroenterologist or general surgeon through our see a relevant specialist directory. If your doctor prescribes iron supplements for anaemia or other medicine, you can check it in our medicine directory. For more on prevention and healthy living, explore our more health tips.

Frequently Asked Questions

Is blood in the stool always cancer?

No. Most rectal bleeding is caused by piles or anal fissures rather than cancer. However, the only way to be sure is to have a doctor examine you, because bowel cancer can cause the same symptom and is far more treatable when found early.

At what age should I start screening for colon cancer?

For people at average risk, screening usually begins around age fifty. If you have a family history of colon cancer or polyps, or other risk factors, your doctor may advise starting earlier. The right timing is best decided with a doctor who knows your history.

Is a colonoscopy painful?

A colonoscopy is generally done with sedation, so most people feel little or no pain and may not remember the procedure. The bowel preparation beforehand is the less comfortable part, but it is important for a clear and accurate examination.

Can a healthy diet alone prevent colon cancer?

A high-fibre diet, regular activity and avoiding tobacco and excess alcohol lower the risk meaningfully, but they cannot remove it entirely. Screening remains important because it can detect and remove polyps before they become cancer.

This article is for general health education and is not a substitute for professional medical advice; please consult a qualified doctor about your own situation.