Bowel cancer is main cause of cancer death in under 50s: new figures

Experts have raised fresh concerns over a ‘tsunami’ of bowel cancer cases – as a new study revealed it has become the leading cause of cancer deaths in under 50s.

Research published by the American Cancer Society (ACS) this month found that the disease – also known as colorectal cancer – is killing people aged between 20 and 49 years old at unprecedented rates.

The worrying study revealed that there is around a three per cent increase of young adults being diagnosed with bowel cancer every year, with 158,850 new cases and 55,230 deaths predicted in the US in 2026.

With analyses last year also uncovering that bowel cancer cases are on the rise in under 50s across nations including Britain, Australia and Canada, there are growing fears about the uptick in the disease.

Dr Ahmedin Jemal, senior vice president of surveillance, prevention and health services research at the ACS, said: ‘It’s clear that colorectal cancer can be longer be called an old person’s disease.

‘We must double down on research to pinpoint what is driving this tsunami of cancer in generations born since 1950.’

Bowel cancer is responsible for around 17,700 deaths in Britain every year and is the second–most common cause of cancer death across the nation.

The most recent statistics published by Cancer Research UK also revealed that rates of overall cancer diagnoses in 25 to 49-year-olds in Britain had increased by 24 per cent.

While they believe part of this trend is to do with an increasing population and improvements in diagnosis, experts remain concerned.

‘Over recent decades, there has been a clear increase in cancer incidence rates in young adults in the UK,’ Professor Charles Swanton, Cancer Research UK’s chief clinician said in 2024.

‘Evidence suggests that more adults under 50 may be getting cancer than ever before.’

One of the concerns in the research surrounded early-onset cancers, particularly bowel cancer.

Dr Aparna Parikh, a professor of medicine at Harvard medical school and an oncologist at Massachusetts general hospital, said at the time: ‘This is complex, and the rise in early-onset colorectal cancer cases is driven by various factors, including diet, the environment, and features of the microbiome. 

‘A greater understanding of why cancer cases are rising can help us understand how to intervene and identify high risk patients for cancer screening. 

‘By trialling methods to assess risk and prevent early-onset colorectal cancers, we can shape a hopeful and healthier future for younger generations.’

The ACS’s most recent study analysed cancer statistics and mortality rates from the US population, and found that there had been a steady increase of bowel cancer deaths by one per cent since 2004.

It also found that rectal cancer now accounts for 32 per cent of bowel cancer cases in the US, up from 27 per cent in the mid-2000s.

Rectal cancer affects the rectum – the final section of the large intestine where stool is stored before it is passed from the body.

This differs from colon cancer, which develops higher up in the large bowel. Together, cancers of the colon and rectum are often grouped under the umbrella term ‘bowel cancer’.

It is unclear why this is the primary driver of the surge, but recent research has honed in on diets that are high in fat but low in fiber, as these contribute to constipation and stool sitting in the lower colon for longer periods of time, allowing bacteria to damage cell DNA.

Processed meats and environmental contaminants such as pesticides also increase exposure to potential carcinogens that end up in stool that sits in the rectum.

‘The trend is very serious,’ the study’s authors told Live Science. ‘Colorectal cancer is the only common cancer (in people) under 50 with rising mortality.’

With cases on the rise in Britain, the Daily Mail asked Dr Angad Dhillon, a consultant gastroenterologist, how to keep bowel cancer at bay earlier this month.

He said: ‘There are many preventative measures people can take to reduce the risk. 

‘Eating a diet rich in plants and fibre, maintaining a healthy weight, staying physically active, avoiding smoking, keeping alcohol within recommended limits and managing stress all play an important role in maintaining a healthy gut.’