Colon Cancer in Your 30s: 4 Signs Doctors Want You to Spot

While often perceived as a disease affecting older adults, colon cancer is increasingly diagnosed in younger individuals, including those in their 30s. This alarming trend underscores the importance of recognizing potential warning signs and seeking timely medical attention. According to the American Cancer Society, colorectal cancer is the third most common cancer diagnosed in both men and women in the US. In 2025, about 107,320 new cases of colon cancer were expected.

Here are four key signs that doctors want you to be aware of:

1. Unexplained Fatigue: Feeling unusually tired or sleeping more than usual could be a subtle indicator. Colon cancers can bleed slowly over time, leading to iron deficiency anemia and low hemoglobin levels. Reduced oxygen delivery due to low blood levels can result in persistent fatigue. If fatigue lingers, it's advisable to get a blood count.

2. Night Sweats: Drenching night sweats can occur when tumors trigger inflammatory signals in the body. While night sweats aren't exclusive to cancer, they warrant attention, especially when accompanied by fever or unexplained weight loss. Persistent night sweats should be tracked and discussed with a healthcare professional.

3. Changes in Bowel Habits: New or persistent constipation or diarrhea that lasts for more than a few weeks requires medical evaluation. A growing tumor can narrow the colon, altering stool flow and leading to changes in bowel habits. Other changes to watch out for include persistent changes, pencil-thin stools or increased urgency.

4. Blood in Stool: Blood in the stool is a significant red flag. Bright red blood may originate from the lower colon or rectum, while darker maroon stool can indicate bleeding higher up in the digestive tract. While hemorrhoids can also cause rectal bleeding, repeated or persistent bleeding necessitates prompt testing to rule out more serious causes.

It's important to note that these symptoms can also be caused by other, less serious conditions. However, given the rising incidence of colon cancer in younger adults, it's crucial to be vigilant and consult a doctor if you experience any of these signs. Early detection is critical for improving outcomes.

Why is Colon Cancer Rising in Young Adults?

The exact reasons for the increase in early-onset colon cancer are still being investigated. However, several factors are believed to play a role:

• Diet: A diet high in processed foods, red meat, and sugary drinks, and low in fiber, fruits, and vegetables may increase the risk.
• Obesity and Sedentary Lifestyle: Lack of physical activity and excessive weight are linked to higher rates of colon cancer.
• Gut Microbiome Changes: Alterations in gut bacteria, possibly due to antibiotic use or other factors, may contribute to increased risk.
• Genetics: While only a minority of early-onset cases are due to inherited conditions like Lynch syndrome or familial adenomatous polyposis (FAP) , having a family history of colon cancer significantly increases your risk.
• Lack of Screening: Younger individuals are less likely to be screened for colon cancer unless they exhibit symptoms. Current guidelines recommend that people at average risk begin screening at age 45.

What You Can Do

• Know Your Risk Factors: Be aware of your family history, lifestyle habits, and any pre-existing conditions that may increase your risk.
• Adopt a Healthy Lifestyle: Eat a balanced diet, maintain a healthy weight, exercise regularly, and avoid smoking and excessive alcohol consumption.
• Don't Ignore Symptoms: Pay attention to any changes in your bowel habits, unexplained fatigue, or other concerning symptoms, and promptly report them to your doctor.
• Talk to Your Doctor About Screening: If you have a family history of colon cancer or other risk factors, discuss with your doctor whether earlier screening is appropriate for you. Screening options include stool-based tests and visual exams like colonoscopies.

By staying informed and proactive, individuals in their 30s can play a crucial role in the early detection and prevention of colon cancer.