However, anemia itself has many possible causes.

Iron-deficiency anemia—especially when the cause is unexplained—should be evaluated rather than automatically attributed to diet.

6. A Feeling That Your Bowel Isn't Empty

Some people with colorectal problems describe a sensation that they still need to use the bathroom even after having a bowel movement.

This is sometimes called tenesmus.

It can feel like pressure, an incomplete bowel movement, or an ongoing urge to go.

This symptom can occur for many reasons, including inflammatory bowel conditions and other disorders affecting the rectum.

But if it is persistent or represents a major change from your normal bowel habits, it is worth discussing with a healthcare professional.

7. Changes in Stool Appearance

People sometimes notice that their stool looks different.

One change that can attract attention is consistently narrow or ribbon-like stool.

However, stool shape can naturally vary depending on diet, hydration, bowel movements, and other factors.

A single unusual bowel movement is generally not a reason to assume something is wrong.

The bigger concern is a persistent change in stool form, especially when it occurs alongside other symptoms such as bleeding, abdominal discomfort, or a change in bowel habits.

8. Iron-Deficiency Anemia Without an Obvious Explanation

This deserves special attention.

Iron-deficiency anemia can develop for many reasons, including inadequate dietary iron, menstrual blood loss, pregnancy, malabsorption, and other medical conditions.

But unexplained iron-deficiency anemia—particularly in adults who do not have an obvious source of blood loss—can sometimes be associated with gastrointestinal bleeding.

For that reason, healthcare professionals may recommend investigating the digestive tract depending on the person's age, sex, symptoms, medical history, and laboratory results.

Anemia is not a diagnosis of colon cancer.

It is a clue that there may be an underlying problem that needs to be identified.

Symptoms Can Be Subtle—or Completely Absent

One of the most important facts about colorectal cancer is that early disease may cause no symptoms at all.

That means waiting until you feel something unusual is not always a reliable strategy.

Screening exists precisely because cancer and precancerous changes can sometimes be found before symptoms develop.

Screening recommendations vary by country and by individual risk.

In the United States, for example, average-risk adults are generally advised to begin colorectal cancer screening at age 45, while people with certain risk factors may need to begin earlier or undergo screening more frequently.

If you have a family history of colorectal cancer or certain polyps, inflammatory bowel disease, or another elevated-risk condition, ask your healthcare professional when screening should begin.

Why Screening Matters

One of the biggest advantages of colorectal cancer screening is that it can detect problems before they become advanced.

Depending on the test, screening may look for:

• Blood in stool

• Abnormal DNA markers in stool

• Polyps

• Early cancers

Colonoscopy has an additional advantage: if certain polyps are found, they can often be removed during the procedure.

Other screening options include stool-based tests and certain imaging procedures.

The best screening method depends on individual circumstances, medical history, risk factors, availability, and personal preferences.

The important thing is not to ignore screening simply because you feel healthy.

Risk Factors You Should Know

Colorectal cancer can affect people without obvious risk factors, but certain factors can increase risk.

These include:

Age

Risk generally increases as people get older, although colorectal cancer can also occur in younger adults.

Family History

Having a close relative with colorectal cancer or certain types of polyps can increase your risk.

Previous Polyps

Some types of colorectal polyps can become cancerous over time.