Colon Cancer: Symptoms, Causes, Prevention and Screening

Colon Cancer: The Silent Warning We Must Never Ignore

Have you ever ignored a change in your bowel habits because you thought it was just something you ate? Have you ever noticed blood in your stool and hoped it would disappear on its own?

Many people do exactly that. They feel embarrassed, blame their diet, or postpone visiting a doctor because they feel perfectly healthy.

But sometimes, the body is trying to tell us something important.

Colon cancer, also called colorectal cancer when it affects the colon or rectum, is one of the world's most serious health challenges. It can develop quietly, and some people have no noticeable symptoms until the disease has progressed.

The recent death of Brazilian actress and singer Lua Blanco at age 39, reported on October 19, 2026, following complications of intestinal cancer, is a painful reminder that this disease can affect younger adults, too.

This is not an article about living in fear. It is about knowing the warning signs, understanding our risks, and taking action while we can.

1. What Is Colon Cancer?

Colon cancer begins in the colon, the main part of the large intestine. When cancer develops in the rectum, the final section of the large intestine, it is called rectal cancer. Together, these diseases are known as colorectal cancer.

The digestive system processes food, absorbs nutrients and water, and prepares waste for elimination.

Sometimes, cells lining the colon or rectum develop abnormal growths called polyps. Some polyps can gradually become cancerous, although most polyps do not become cancer.

This is one reason screening is so important: doctors can sometimes find and remove precancerous polyps before they turn into cancer.

Screening can identify colorectal cancer early and help prevent some cases

2. The Global Statistics Are Alarming

According to the World Health Organization, colorectal cancer was responsible for approximately 1.9 million new cases and more than 900,000 deaths worldwide in 2022.

It was the third most common cancer worldwide and the second leading cause of cancer-related death.

The WHO also warns that although the disease is more common after age 50, cases among younger adults are increasing in some settings.

In Brazil, the National Cancer Institute (INCA) estimates approximately 53,810 new colorectal cancer cases annually for 2026–2028.

These numbers represent real people, families, and futures that may be changed by earlier detection.

Sources: WHO, Colorectal Cancer Fact Sheet (2026); Brazilian National Cancer Institute estimates, as reported by CNN Brasil in October 2026.

3. Why Does Colon Cancer Develop?

There is no single cause. Colorectal cancer usually develops through a combination of biological, genetic, environmental, and lifestyle factors.

Some of the factors associated with increased risk include:

Age: The risk rises as we get older, particularly after age 50, although younger people can also develop the disease.

Family history: Having a close relative who had colorectal cancer or certain precancerous polyps can increase your risk.

Inherited conditions: Conditions such as Lynch syndrome and familial adenomatous polyposis can significantly increase risk.

Diet: Regularly eating large amounts of processed meat, and high consumption of red meat, are associated with increased risk. A diet low in fibre-rich plant foods may also contribute.

Physical inactivity and excess body weight: These are associated with a greater risk of colorectal cancer.

Smoking and alcohol: Both are linked to an increased risk.

Previous polyps or colorectal cancer: A personal history of certain polyps or cancer can mean a greater need for monitoring.

However, having one or more risk factors does not mean someone will definitely develop cancer. Equally, a healthy lifestyle does not eliminate every risk.

4. Warning Signs You Should Never Ignore

One of the challenges with colorectal cancer is that it may cause no symptoms in its early stages.

When symptoms do appear, they may include:

• Blood in or on your stool, whether bright red or dark.

• A persistent change in bowel habits, including diarrhoea or constipation.

• Stools that become consistently narrower than usual.

• A feeling that your bowel has not emptied completely.

• Abdominal cramps, pain, or bloating that does not go away.

• Unexplained weight loss.

• Persistent tiredness or weakness, sometimes caused by iron-deficiency anaemia.

These symptoms do not automatically mean cancer. Haemorrhoids, infections, inflammatory bowel conditions, and other problems can cause similar symptoms.

Nevertheless, do not assume that blood in your stool is simply haemorrhoids, and do not wait for pain before seeking medical advice.

If you experience persistent symptoms, arrange a medical assessment promptly. Significant bleeding, severe abdominal pain, fainting, or black, tar-like stools accompanied by weakness require urgent medical attention.

5. Can We Prevent Colon Cancer?

We cannot prevent every case, but we can reduce some risks and improve the chances of finding the disease early.

Here are practical steps worth adopting.

Eat more fibre-rich foods. Include beans, lentils, vegetables, fruits, whole grains, and other plant foods in your meals.

Limit processed meat. Reduce foods such as sausages, bacon, ham, and other processed meats. Consider replacing some red-meat meals with beans, fish, poultry, or other nutritious alternatives.

Move your body regularly. Walking, cycling, swimming, dancing, and other activities you enjoy can help. Start at a manageable level and build a routine.

Maintain a healthy weight. Aim for sustainable eating and physical activity rather than extreme diets.

Avoid tobacco and limit alcohol. Not smoking and avoiding alcohol can reduce several cancer-related health risks.

Know your family history. Ask whether close relatives have had colorectal cancer or significant polyps, particularly at younger ages.

Do not skip screening. Screening can detect cancer before symptoms develop and, in some cases, prevent cancer by identifying and removing precancerous polyps.

Remember: no detox drink, herbal remedy, supplement, or special diet has been proven to replace colorectal cancer screening.

A balanced, fibre-rich eating pattern supports overall health and may help reduce colorectal cancer risk.

6. At What Age Should You Get Screened?

Screening recommendations differ by country, available resources, family history, and personal risk.

For example, the American Cancer Society recommends that adults at average risk in the United States begin regular colorectal cancer screening at age 45. Other countries may use different starting ages or screening programmes.

Depending on local availability and individual circumstances, screening may involve:

• Stool-based tests: These look for signs of blood or other indicators in a stool sample. Some tests are designed to be completed at home.

• Colonoscopy: A doctor examines the inside of the colon and rectum using a flexible camera. Polyps may be removed during the procedure.

• Other tests: Flexible sigmoidoscopy and other screening approaches may be available in certain settings.

A positive stool test generally requires follow-up, often with a colonoscopy.

If you have symptoms, a strong family history, or an inherited risk condition, do not wait until the usual screening age. Speak with a healthcare professional about the appropriate assessment.

In Mozambique and other countries where screening access may be limited, ask a local health facility what tests and referral services are available.

7. What Happens If Colon Cancer Is Diagnosed?

A diagnosis of cancer can be frightening. But it does not mean that every person has the same outlook or treatment options.

Treatment depends on where the cancer is located, its stage, the tumour's characteristics, and the patient's overall health.

Options may include:

• Surgery: Removing the cancer and, when necessary, nearby tissue or lymph nodes.

• Chemotherapy: Using medicines to destroy cancer cells or control their growth.

• Radiotherapy: Using radiation, particularly in the treatment of some rectal cancers.

• Targeted therapy or immunotherapy: Treatments that may help selected patients depending on the cancer's characteristics.

Some early-stage cancers can be treated successfully. Advanced cancers can be more difficult to cure, but treatment may still control the disease, relieve symptoms, and help people live longer.

If you or someone you love receives this diagnosis, ask the medical team about the stage, treatment choices, expected benefits and side effects, nutrition, emotional support, and follow-up care.

A second medical opinion can also be reasonable when it is feasible.

8. How Can Someone Live Better With Colon Cancer?

Regular physical activity is one practical step toward lowering certain cancer risks.

Living with cancer involves more than treating the tumour. It also means supporting the whole person.

Eat according to your needs. Treatment may change appetite, digestion, and bowel habits. A qualified dietitian or healthcare professional can help you adapt your meals.

Stay active when possible. Gentle movement may help maintain strength, mood, and independence. Follow your treatment team's advice, especially after surgery or during intensive treatment.

Protect your emotional health. Fear, sadness, anger, and uncertainty are understandable. Talk with trusted people, counsellors, support groups, or your healthcare team.

Keep follow-up appointments. Monitoring helps doctors assess recovery, manage side effects, and detect possible recurrence.

Ask for practical help. Transport, appointments, meals, and everyday tasks can become difficult during treatment. Support from family and friends matters.

Be careful with supplements. Some herbal products and supplements can interfere with cancer treatment. Discuss them with your medical team before using them.

A cancer diagnosis may change someone's life, but people deserve care, dignity, companionship, and the best available treatment at every stage.

9. Frequently Asked Questions About Colon Cancer

Can you have colon cancer without symptoms?

Yes. Early colorectal cancer and precancerous polyps may cause no noticeable symptoms. This is why screening matters even when you feel healthy.

Does blood in the stool always mean cancer?

No. Haemorrhoids, fissures, infections, and other conditions can cause bleeding. However, unexplained or recurrent bleeding should be medically assessed.

Can young people get colon cancer?

Yes. Although the risk increases with age, colorectal cancer can occur in younger adults. Persistent warning signs should not be dismissed because someone is young.

Does eating healthy guarantee that I will not get colon cancer?

No. A healthy lifestyle can reduce certain risks, but it cannot eliminate them. Screening and awareness remain important.

Is colon cancer curable?

Some colorectal cancers can be cured, particularly when found early. Outcomes vary depending on the stage, tumour biology, and treatment options.

Is a colonoscopy painful?

Many patients receive sedation or other comfort measures. Some temporary discomfort, bloating, or cramping may occur. Ask the healthcare team about preparation, risks, and available options.

Should I get tested if I feel completely healthy?

If you are within your country's recommended screening age, or have increased risk because of family history or other factors, ask your healthcare professional about screening. Do not rely on symptoms alone.

10. A Final Message: Do Not Let Embarrassment Put Your Health at Risk

We speak openly about heart disease, diabetes, blood pressure, and many other conditions. Yet bowel symptoms can remain hidden behind embarrassment and silence.

There is nothing shameful about talking to a doctor about your bowel movements. They are an important part of your health.

We may not control every disease that comes our way, but we can learn the warning signs, understand our family history, make healthier choices, and seek help when something changes.

Please remember three things: know your risk, take screening seriously, and never ignore persistent warning signs.

Share this article with a friend, a parent, a partner, or someone who might need the information. One conversation could encourage someone to seek care earlier.

At Hopajuinc, we believe that better health begins with better information.

Your turn: Did you know that colorectal cancer can develop without obvious symptoms? What do you think stops people from seeking screening or talking openly about bowel health? Share your thoughts in the comments.

Health disclaimer: This article is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional about symptoms, screening, and treatment. The author is not a medical adviser. If affiliate links appear on this page, Hopajuinc may earn a commission at no additional cost to you.