Faster ageing among young adults could explain why more under-50s are getting cancer, researchers have said.
Between 1990 and 2019, cancers diagnosed in patients under the age of 50 years increased by 24 per cent globally and continue to rise.
In a study published in Nature Medicine, scientists studied 154,169 individuals from the UK biobank and 10,000 people from the US.
Their findings suggested that accelerated biological ageing is associated with “a higher risk of developing multiple cancers earlier in life, specifically early-onset lung cancer, colorectal cancer and uterine cancer”.
Biological age differs from chronological age and reflects how well the body is functioning and can be influenced by factors such as diet, exercise, environment and overall health.
To determine biological age, researchers used information from blood samples and other health data to estimate whether a person’s body appeared “older” or “younger” than expected for their age.
They used an established algorithm called PhenoAge, which combines nine routine blood test results that reflect things like blood sugar control, inflammation and immune system function.
Dr Yin Cao, associate professor of surgery and of medicine at Washington University School of Medicine, said: “Biological ageing isn’t just about the number of birthdays you’ve had — it reflects wear and tear happening inside the body at a cellular and molecular level.
“This can include changes that affect how cells and tissues function, such as chronic inflammation, weakening of the immune system and damage building up in cells over time.”
“Wear and tear markers” such as inflammation and DNA damage could be caused by unhealthy lifestyles or exposure to pollutants.
The team looked into organ-specific measures of ageing using proteomics approaches, finding links between immune ageing and early-onset lung cancer as well as adipose tissue ageing and early-onset colorectal cancer.
Dr David Scott, who worked on the research, said: “Right now, we don’t have a definitive answer to what’s driving the rise of early-onset cancers around the world, but studies like this are helping us piece together the bigger picture, showing that cancer may be influenced not just by changes inside individual cells, but by wider changes happening across the body as a whole.
“These findings suggest that accelerated biological ageing could reflect the combined impact of our lifestyles and environments on the body over time, potentially helping explain why some cancers are appearing earlier in younger generations.”
The study was part of Team Prospect, a group set up to investigate rising cancer in the young as part of a global initiative called cancer grand challenges, funded by Cancer Research UK and the American National Cancer Institute.