✓ Evidence Based

 9 Signs and Symptoms of Colon Cancer

Colon cancer, also known as colorectal cancer, is often called the silent killer because there may be no symptoms until the tumor has become large enough to cause problems.

Over 100,000 new cases of colon cancer are reported each year in the U.S. It is actually the third most common cancer in both men and women, and is responsible for nearly 50,000 deaths each year.

Colon cancer is a disease in which the cells in the large intestine become abnormal and multiply uncontrollably.

Signs and Symptoms of Colon Cancer

While there’s no way to know for sure whether colon cancer will develop, there are some symptoms that might indicate a problem. Some signs mentioned in this article may be subtle, while others may be more obvious.

1. Changes in bowel habits

The average age when you’re most likely to get colon cancer is 60 years old. Half of the people diagnosed with colon cancer are over 65 years old but younger people can get it too.

Bowel habits are often the first sign of colon cancer. A healthy colon usually has a regular bowel movement every day or two. The stool should be soft, brown, and easy to pass, with no blood.

If you notice any changes in how often you go to the bathroom or if your stools become hard and difficult to pass, it might be something concerning to look after.

2. Diarrhea

Diarrhea, or loose bowel movements, is a common problem for people with colon cancer. The term diarrhea technically refers to the passage of three or more unformed stools in a 24-hour period.

Diarrhea is a symptom that can also be caused by other conditions, including irritable bowel syndrome, lactose intolerance, and inflammatory bowel disease.

The National Cancer Institute reports that some people may experience diarrhea because their colons are infected with bacteria or parasites.

3. Constipation

It’s no secret that the colon is responsible for waste elimination. It’s also responsible for the absorption of water and nutrients from the food we eat. This can lead to a situation where the colon becomes clogged and unable to function properly. The result is constipation, which can be quite uncomfortable and embarrassing.

Constipation may not seem like much of a problem at first, but it can be an early sign of colon cancer. In fact, according to one study, more than 80 percent of patients diagnosed with colon cancer had experienced constipation before their diagnosis.

Constipation can be caused by a variety of things, including medication side effects and a lack of physical activity. Sometimes it’s hard to tell the difference between normal constipation and something more serious like colon cancer.

If you’re experiencing constipation that lasts longer than three days, talk to your doctor — especially if other symptoms such as bloody stools and abdominal pain are present.

4. Blood in your stool

Colon Cancer is one of the most treatable cancers. If detected early, the five-year survival rate for colon cancer is 95%. Unfortunately, 1 in 20 Americans will develop colon cancer during their lifetime. The earlier it is detected, the higher the survival rate.

Blood in your stool can be an early sign of colon cancer. The colon is the part of your digestive system that stores stool before it’s eliminated from the body. Bloody stools can be caused by many different types of cancer and other conditions, such as ulcerative colitis, diverticulitis, and hemorrhoids.

Blood in the stool is usually due to inflammation or injury in the large intestine. It can also be from bleeding from other parts of the digestive tract, such as from ulcers in the stomach.

A bloody stool can also be caused by certain medicines, such as Antibiotics like ciprofloxacin, Antidiarrheal drugs such as lactulose, or Iron supplements.

5. Bleeding from the rectum

Bleeding from the rectum might be a sign of colon cancer. The rectum is the last part of your large intestine, which is about five inches long. It’s where waste leaves your body. However, bleeding from the rectum is fairly common and most people with this symptom do not have colon cancer.

A number of other conditions that can cause bleeding in this area, are hemorrhoids and anal fissures. Bleeding from the rectum may also be caused by a polyp or other growth on the surface of your colon.

6. Unexplained bloating or abdominal pain

Colon cancer can be caused by genetics or lifestyle choices such as diet and exercise habits, which can increase your risk by up to 30%. Genetics accounts for 10% to 15% of all cases of colon cancer while other factors such as poor diet, obesity, smoking, and alcohol use account for 5% to 10% risk increase.

Bloating is one of the most common symptoms of colon cancer. It can occur in the early stages of the cancer, or it may be a symptom of other conditions that have nothing to do with cancer.

Bloating is a feeling of fullness or swelling in the abdomen that can be caused by gas. It can also happen because of certain foods or medications.

If your belly feels swollen after you eat, try eating smaller meals more often throughout the day instead of three large meals every day. This will help prevent bloating caused by overeating and should also help control blood sugar levels.

7. Feeling constantly tired

The symptoms of colon cancer often develop slowly and have no clear warning signs. Feeling tired is quite common and can be caused by a number of factors, including being tired from staying up late, or not getting enough sleep.

However, if you find yourself feeling tired more often than usual and it doesn’t go away after a good night’s sleep, it could be a sign that something is wrong with your body.

The colon is responsible for removing waste from the body through the stool. When this process becomes blocked or slows down, toxic buildup can occur in the digestive system. If this continues over time, it can lead to cancerous tumors in the colon wall. If you feel tired often and notice any other symptoms such as bloating or abdominal pain, this might be an early sign of colon cancer.

8. Sudden weight loss

Colon cancer symptoms vary depending on where the tumor is located and how advanced it is. Sudden weight loss can be an early sign of colon cancer, as well as other gastrointestinal diseases.

But it also can occur for other reasons. Notably, if you’re an older adult and have overcome an illness it is completely normal to have shedded off some extra pounds! If you’ve lost more than 10 pounds or 15 pounds over several months, this might be a sign of colon cancer.

9. Feeling full all the time

A healthy diet can help lower your risk of developing colon cancer, but it may not be enough. When it comes to preventing colon cancer, exercise is also important. If you’re feeling full all the time even when you do not eat food, this could be a sign that you have a problem with your digestive tract.


Colon cancer may cause bloating, constipation, diarrhea, and other digestive issues that make it difficult for people to eat normally. These symptoms are often mild at first and are generally easier to ignore or dismiss than other symptoms of colon cancer. In fact, if you have any other symptoms like weight loss or fatigue, you may think your problems are something else entirely and not seek treatment right away.

Whether you’re sixty-one or sixteen, the best way to prevent the disease is to eat healthy foods, exercise, and maintain a normal weight. Doing so will keep your colon clean!

If one first-degree relative such as a parent, child, or sibling has had colorectal cancer before age 55, you have a greater risk than average of developing it yourself at some point in your life. If two first-degree relatives have had colorectal cancer before age 55, you have an even greater risk than average.

African Americans have the highest risk of developing colon cancer than other races and ethnicities in the U.S. Although, this may be due to differences in access to screening tests rather than biology alone.

Remember, if you have any of the symptoms discussed above, do not wait before contacting your doctor. Keep in mind that these may be early signs of colon cancer, not definitive symptoms. And if you do have any of the risk factors for colon cancer discussed above, be sure to discuss with your doctor whether colonoscopies would be the most appropriate decision for screening.