The rise of colorectal cancer in under-50s is alarming health experts around the world. Once seen as a disease that mainly affected older adults, bowel cancer is now increasing among younger people — and researchers still do not know exactly why.
Recent high-profile deaths have brought attention to the issue. US actor James Van Der Beek died at 48 after being diagnosed with colorectal cancer. In 2020, Chadwick Boseman, best known for his role in Black Panther, died from the same disease at age 43.
A Growing but Still Rare Trend
Experts stress that the overall number of cases among young people remains relatively low. According to research published in JAMA, colorectal cancer is now the leading cause of cancer death among under-50s in the United States.
However, only about six percent of all colorectal cancer cases occur in people under 50. Most diagnoses still happen in older adults.
Rates among older people have stabilised or even declined in some countries. This is largely due to improved screening programmes and better awareness.
What Is Causing the Increase?
Doctors say traditional risk factors do not fully explain the surge.
Common risk factors include:
- Being overweight
- Poor diet
- Lack of exercise
- Smoking
- Heavy alcohol use
While these factors play a role, experts say they do not account for the sharp rise in younger adults over a short period.
Researchers are now looking closely at the gut microbiome — the community of bacteria living in the digestive system.
A recent study published in Nature found an important clue. It showed that DNA mutations linked to a toxin called colibactin were more common in younger colorectal cancer patients. This toxin is produced by certain strains of E. coli bacteria.
However, scientists still do not know why younger people may be more affected. More research is needed.
There is also growing interest in whether frequent antibiotic use could increase the risk. But no single cause has been identified.
Experts believe the rise is likely due to several factors working together.
Symptoms Young People Should Not Ignore
One major concern is that younger people often do not think they are at risk. This can delay diagnosis.
Common symptoms include:
- Changes in bowel habits (diarrhoea or constipation)
- Blood in stool
- Unexplained weight loss
- Ongoing fatigue
Because symptoms can be mild at first, many cases are diagnosed at a later stage.
Screening Age Is Changing
In 2021, the United States lowered the recommended screening age from 50 to 45. Health experts are now debating whether other countries should do the same.
Currently, the UK and France begin routine screening at age 50.
Doctors urge anyone experiencing symptoms — regardless of age — to speak to a healthcare provider.
The rise in colorectal cancer in under-50s remains a mystery. But one message is clear: awareness and early detection can save lives.
