Colon Cancer in Young Adults

Author: Dr. Ron Hunninghake, MD

The star of the movie Black Panther, Chadwick Boseman, died at age 43 of early-onset colon cancer after a 4-year struggle against the disease. His death has spotlighted the fact that colon cancer has been increasingly affecting younger adults over the past decade.

Why Are Young Adults Getting Colon Cancer?

The third most common cause of cancer diagnosed in men and women in the U.S. is rising. In 2004, newly diagnosed colorectal cancer in people under age 50 was approximately 10%.1 By 2015, this rate rose to 12.2%.1 However, the real tragedy is that 50%1 of these younger patients were diagnosed at later stages of the disease.

Vague Abdominal Symptoms

Colorectal cancer symptoms tend to be very nonspecific. Obvious bowel cancer symptoms include rectal bleeding or a significant change in bowel habits. More subtle symptoms, like mild abdominal pain or cramping, that won’t go away can herald early cancer but often goes unnoticed.

Links to Ethnicity

Colorectal cancer rates also differ by ethnicity, with rates being 20% higher in African Americans than non-Hispanic whites.2 The rate of death is also 40% higher in this group.2 African Americans low vitamin D levels due to darker skin and poor outdoor sun exposure time have been implicated. Family history is another possible link. Almost one-third of colorectal cancers are diagnosed in patients 35 or younger who report similarly afflicted close family members.


Metabolic Syndrome is often associated with obesity and diabetes. Altered glucose metabolism may also link obesity to colorectal cancer, with high levels of pro-proliferative insulin and related growth factors promoting tumorigenesis,3 the production or formation of a tumor or tumors. Obesity can also induce a chronic inflammatory state because body fat, also known as adipose tissue, secretes inflammatory cytokines (small proteins important in cell signaling). Overactive cytokines can contribute to carcinogenesis, according to Marc Gunter, Ph.D. of the International Agency for Research on Cancer.3 Lower physical activity and more sedentariness, which is increasing in younger adults, are also risk factors for colorectal cancer.

Gut Microbes

Elevated levels of certain gut microbes and low microbial diversity are associated with greater colorectal cancer risk.3 Diet, obesity, and physical activity significantly affect the gut biome. Pathogenic bacteria-derived compounds can leak into the colorectal mucosa, the moist inner lining of some organs and body cavities, and promote the above-noted inflammation.3

The pervasive use of glyphosate (Roundup) on crops and lawns has resulted in widespread contamination of common foods and drinking water.4 In addition, glyphosate interferes with the Shikimate Pathway in gut bacteria, further eroding a healthy gut biome.5 How changes in the gut microbiome specifically play a role in colorectal cancer remains unclear. 

Folic Acid Supplementation

Nationwide fortification of enriched uncooked cereal grains with folic acid began in the United States and Canada in 1996 and 1997, respectively, and became mandatory in 1998. The rationale was to reduce the number of births complicated by neural tube defects. Concurrently, the United States and Canada experienced abrupt reversals of the downward trend in colorectal cancer incidence that the two countries had enjoyed in the preceding decade. In each country, the increase in colorectal cancer incidence from the pre-fortification trend falls significantly outside of the downward linear fit based on nonparametric 95% confidence intervals.6 In addition, changes in the rate of colorectal endoscopic procedures do not seem to account for this increase in colorectal cancer incidence.6 These observations alone do not prove causality but are consistent with the known effects of folate on existing neoplasms, as shown in both preclinical and clinical studies.6 Common folic acid fortified foods include processed boxed cereals and low fiber white bread.

Screening and Early Warning Signs

Colorectal Screening Guidelines

The American Cancer Society recommends that adults at average risk for colorectal cancer begin screening at age 45. People at higher risk may need to start screenings earlier or have them done more often. This type of cancer has over a 90% 5-year survival rate if found early.7 However, that rate drops to about 14% once it spreads to other organs.7

Early Warning Signs

See a doctor if you notice any warning signs, including changes in bowel patterns, straining or discomfort with bowel movements, rectal bleeding, or feeling full or bloated. Also, have a complete blood count blood test to check if anemia has developed, making the rectal bleeding a sign of possible disease.

7 Tips to Lower Your Colon Cancer Risk

  1. Follow a diet high in fiber that includes lots of vegetables, fruits, and organic whole grains with avoidance of processed and factory-farmed meats.
  2. Limit alcohol to no more than two drinks a day for men and one drink a day for women.
  3. Achieve or maintain a healthy weight.
  4. Follow recommended colorectal screening guidelines.
  5. Learn your family medical history.
  6. Exercise regularly.
  7. Don’t smoke.


  1. Virostko, J., Capasso, A., Yankeelov, T. E., & Goodgame, B. (2019). Recent trends in the age at diagnosis of colorectal cancer in the US National Cancer Data Base, 2004-2015. Cancer, 125(21), 3828–3835.
  2. Siegel, R.L., Miller, K.D., Goding Sauer, A., Fedewa, S.A., Butterly, L.F., Anderson, J.C., Cercek, A., Smith, R.A. and Jemal, A. (2020), Colorectal cancer statistics, 2020. CA A Cancer J Clin, 70: 145-164.
  3. Cause of Early-Onset Colorectal Cancer Multifactorial. Cancer Discov 1 June 2020; 10 (6): OF2.
  4. 3 Sirinathsinghji E. “Widespread Glyphosate Contamination in USA.” Institute of Science in Society. 2014. Available at:
  5. 3 Fagan J PhD, Antoniou M PhD, Robinson C MPhil. GMO Myths and Truths 2nd Edition. Earth Open Source. 2014:4.1:205. Available at:
  6. Mason, J. B., Dickstein, A., Jacques, P. F., Haggarty, P., Selhub, J., Dallal, G., & Rosenberg, I. H. (2007). A temporal association between folic acid fortification and an increase in colorectal cancer rates may be illuminating important biological principles: a hypothesis. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology, 16(7), 1325–1329.
  7. Howlader N, Noone AM, Krapcho M, Miller D, Brest A, Yu M, Ruhl J, Tatalovich Z, Mariotto A, Lewis DR, Chen HS, Feuer EJ, Cronin KA (eds). SEER Cancer Statistics Review, 1975-2016, National Cancer Institute. Bethesda, MD,, based on November 2018 SEER data submission, posted to the SEER web site, April 2019.