4 Things Gen Z Need to Know about Colorectal Cancer

Contributed by: Dr Foo Kian Fong

Although colorectal cancer is known to predominantly affect older individuals1, it does not mean that Gen Zs are immune to its risks. In fact, there is a growing concern about the increasing incidence of colorectal cancer in those younger than 50 globally2.

The risk factors associated with colorectal cancer include genetics, obesity, overconsumption of processed and red meats, alcohol, and smoking. The rising incidence of colorectal cancer in younger individuals could thus be attributed to changes in our diet and lifestyle.

Many, however, have expressed doubts at the association between these factors and the increasing incidence of the disease. It is crucial to acknowledge that while these factors may elevate the risk, the incremental increase in risk is relatively small3.

Regardless of the reasons behind the increasing incidence of colorectal cancer, it certainly will not hurt for Gen Zs to take a proactive approach and learn more about the disease. Here are four things Gen Zs need to know about colorectal cancer.

1. Risk factors and lifestyle choices

Colorectal cancer usually starts with a polyp in the colon and over a period of time, due to changes in the gut milieu and genetic changes, it develops into a cancer.

The main risk factors include:

  • Genetics related to a certain gene which can be transmitted from parent to child such as adenomatous polyposis and Lynch syndrome
  • Personal history or family history of colorectal cancer or polyps
  • Inflammatory bowel disease such as Crohn Disease or Ulcerative Colitis
  • Obesity
  • Diabetes Mellitus
  • Red and processed meats
  • Smoking
  • Excessive alcohol
  • Others

Understanding the risk factors associated with colorectal cancer is vital, as certain aspects can be mitigated through lifestyle adjustments. Unhealthy lifestyle choices, such as constantly eating high fat fast food, is associated with an elevated risk of colorectal cancer.

Other manageable factors like cutting down on sugar4 and alcohol, consuming vegetables, dairy products and whole grains5, and leading a more physically active lifestyle, may also help reduce the risk of the consequential disease.

2. Symptoms to look out for

The symptoms of colorectal cancer include :

  • Change in bowel habits (diarrhoea or constipation)
  • Feeling that your bowel does not empty completely
  • Finding blood (either bright red or very dark) in your stool
  • Finding your stools are narrower than usual
  • Abdominal pain especially at night
  • Frequently having gas pains, cramps, or feeling full or bloated
  • Losing weight with no known reason
  • Feeling very tired all the time
  • Having nausea or vomiting

Most of these symptoms are common in younger people especially those with irritable bowel syndrome. If you experience any of these symptoms over a prolonged period and there are risk factors, do not hesitate to consult with your healthcare provider. However, it is important to note that these symptoms are usually not due to cancer.

Additionally, it is important to note that early cancer does not usually cause pain6. Therefore, anyone with these symptoms should see a doctor to be diagnosed and treated as early as possible.

3. Screening tests

Screening for cancer is to do tests to detect colorectal cancer even when there are no symptoms.

In Singapore, the recommended age for screening is 50 years old for individuals with no symptoms7. In the USA, the age to start screening is now 45 years. Although these tests may be of little concern to Gen Zs, it is always good to be aware of the options available. Moreover, early detection of colorectal cancer can improve the effectiveness of cancer treatments.

The following screening tests can be used to detect polyps, cancer, or other abnormalities8

  • Faecal Occult Blood Test (FOBT) or Faecal Immunochemical Test (FIT) can detect tiny amounts of blood in the stool. If this test detects blood, other tests are needed to find the source of the blood. Benign conditions (such as haemorrhoids), can also cause blood in the stool.
  • Colonoscopy allows your doctor to examine your rectum and entire colon using a long, lighted tube (colonoscope). If polyps - benign growths that may lead to cancer - are found, they may be removed.
  • Virtual colonoscopy uses special X-ray equipment to produce pictures of the colon and rectum. A computer assembles these pictures into detailed images that can show polyps and other abnormalities.

4. Treatment options

While each case varies, surgery for colorectal cancer can be very successful even in advanced stages. Although most patients require surgery to excise the affected colon segment, some may need additional chemotherapy and radiation therapy.

For individuals with metastatic colorectal cancer, targeted therapy becomes a viable option in the comprehensive treatment plan.

Moving forward

As colorectal cancer is becoming more common among younger individuals, it is crucial for us to have a basic understanding of the disease. Knowing the risk factors, symptoms, screening tests, treatment options, and support is especially useful in the event that we may face a colorectal cancer diagnosis.

It is important to maintain a healthy lifestyle, which includes eating a plant-based diet, having regular exercise, and getting enough sleep (more than 6 hours a night) to hopefully prevent colorectal cancer.

1“Colorectal Cancer”. World Health Organization, 2023.
2“What’s Driving the Rise of Colon Cancer in Young Adults?”. ASCO Daily News, 2023.
3“Colorectal cancer is rising among younger adults and scientists are racing to uncover why”. CNN, 2023.
4Hur J, Otegbeye E, Joh HK, et al. Sugar-sweetened beverage intake in adulthood and adolescence and risk of early-onset colorectal cancer among women. Gut. 2021.
5Vieira AR, Abar L, Chan DSM, et al. Foods and beverages and colorectal cancer risk: a systematic review and meta-analysis of cohort studies, an update of the evidence of the WCRF-AICR Continuous Update Project. Ann Oncol. 2017.
6“Colorectal Cancer”, PCC.
7“Colorectal Cancer Screening: Why It's Important”. SingHealth, 2021.
8“Colorectal Cancer”, PCC.
POSTED IN Cancer Prevention, Cancer Treatments
TAGS cancer diet & nutrition, colonoscopy
READ MORE ABOUT Colorectal Cancer
PUBLISHED 01 March 2024