Colorectal cancer is on the rise in young people — but colonoscopies aren't routine until age 45. Here's how to know if you need one earlier.

A recent report from the American Cancer Society confirmed that colorectal cancer is on the rise in young people, stating it’s the leading cause of cancer death in men and the second leading cause in women under 50 years old. While colorectal cancer is highly treatable, early detection and prevention are key.

A colonoscopy, which involves using a flexible tube with a tiny camera to examine the colon, is effective at detecting and removing precancerous polyps and can identify other cancerous tissue. However, the screening is typically recommended for individuals ages 45 to 75. Here’s what to know about colonoscopies and colorectal cancer, as well as the situations that might warrant the procedure before the recommended age.

What are the risk factors for colorectal cancer?

Dr. Harika Balagoni, a gastroenterologist at Mayo Clinic Health System in La Crosse, Wis., says that colorectal cancer risk factors can be divided into ones you can modify and ones you can’t. Nonmodifiable factors include age, personal history of colon polyps or cancer, inflammatory bowel disease, family history of colorectal cancer and certain hereditary syndromes. Ethnicity also plays a role, with higher rates in certain groups such as American Indian and Alaska Native populations, African Americans and Ashkenazi Jews.

Factors that can be modified include lifestyle choices, such as smoking, alcohol consumption, a diet high in red meat and being sedentary, along with obesity. Researchers suspect that these risk factors play a role in the rising rates of young people getting cancer, generally, and colorectal cancer in particular, in the U.S. Understanding these factors is important for assessing an individual’s risk and taking preventive measures, like getting a colonoscopy. However, experts say that not everyone with one or more of these risk factors should automatically get a colonoscopy.

Who should get a colonoscopy?

The U.S. Preventive Services Task Force recommends that adults get their first colonoscopy at age 45, which is younger than the longtime previous recommendation of age 50. The Centers for Disease Control and Prevention recommends that people at average risk for colorectal cancer get screened every 10 years from age 45 to age 75. At older ages, you can speak with your doctor to weigh the pros and cons of the procedure.

This timeline changes, however, if the individual has a close family member (so, a parent, child or sibling) who was diagnosed with colorectal cancer. “If you have one of these relatives who had colorectal cancer, you would start the colonoscopy screening at age 40, or 10 years before the diagnosis age of your relative,” Dr. Xavier Llor, the director of the GI Cancer Prevention Program at Yale Medicine, tells Yahoo Life.

What are the symptoms of colorectal cancer?

Not every colonoscopy is routine. For some people, gastrointestinal symptoms prompt them to visit the doctor, who may decide to perform a colonoscopy in order to check for signs of colorectal cancer or another health condition.

“There are certain red flags — symptoms that you should talk to your doctor about that they may recommend a colonoscopy for,” Dr. Peter Stanich, a gastroenterologist with the Ohio State University Comprehensive Cancer Center, tells Yahoo Life.

These symptoms include:

• Changes in bowel habits, such as persistent diarrhea or constipation.

• Rectal bleeding or blood in the stool.

• Abdominal pain, discomfort or cramps.

• Unintentional weight loss.

• Feeling that the bowel doesn’t empty completely.

• Iron deficiency anemia.

• Unexplained fatigue.

These symptoms are not definitive proof you have colorectal cancer, as many gastrointestinal issues can cause similar symptoms. However, Stanich urges everyone — especially young people — to speak to their doctor as soon as possible if they are experiencing any of these symptoms.

“It certainly could be something like irritable bowel syndrome or lactose intolerance, which are very, very common, but you should talk to your doctor about it before putting it aside,” he says. “We know that young people with symptoms often have delayed investigation, which means colorectal cancer can be found too late.”

Health care providers can also assess whether a colonoscopy is necessary. Stanich notes that having a colonoscopy can come with some risk, such as infection, perforation of the intestine and bleeding. It’s important to point out that these complications are rare, but they can be potentially life-threatening, which is why he says that “even though it’s a safe test, if you don’t need one, we don’t want to put people through it.”

But what happens if your doctor doesn’t think you need a colonoscopy? Llor says it’s crucial to advocate for yourself. While many doctors are aware of the rising rates of colorectal cancer in young people, making them more likely to recommend necessary colonoscopies, he says it’s important that patients are “being heard” when going to the doctor and should “perceive that our physician is paying attention to what we’re saying.”

This article was originally published on Jan. 19, 2024 and has been updated.