Your body may be older than you think — raising cancer risk

As cancer rates rise in adults younger than 50, research suggests that younger generations may be aging faster biologically than earlier generations did at the same age. And that seems to include higher risk of early onset lung, gastrointestinal, uterine and colorectal cancers.

The risk of developing cancer has typically risen with age. But younger adults are increasingly receiving a cancer diagnosis, according to findings of a study led by researchers at the Washington University School of Medicine in St. Louis. They reported in a news release that “each newer generation appears to face a greater risk than the one before it.” So the team set out to explore whether younger generations “are accumulating biological damage more quickly, causing their bodies to age faster than expected.”

If so, why? It’s a question being explored by an international team that besides the university includes Siteman Cancer Center at Barnes-Jewish Hospital and Cancer Grand Challenges, a global initiative that the National Cancer Institute and Cancer Research U.K. co-founded.

They looked at aging in two large study populations, one in the U.S. and the other in the UK. Both showed generational differences. The findings were published in the journal Nature Medicine.

Some cancers are considered early onset if they occur before age 50 or age 55, depending on the source. As Deseret News has previously reported, while cancer has been declining in older generations — some thanks owed to early detection and better treatment — 17 types of cancer are showing up more often and in younger people than in previous generations.

Among those cancers are breast, pancreatic and gastric, as well as liver cancer in females, uterine corpus, gallbladder, testicular and colorectal cancers, according to a 2024 study by the American Cancer Society published in the journal The Lancet Public Health.

“If we can identify younger people with the highest cancer risk when they are still healthy, we can focus on prevention and early-detection strategies for the individuals who will benefit most from early interventions,” said Yin Cao, a molecular epidemiologist and associate professor of surgery and of medicine at Washington University Medicine, quoted in the news release for the new study.

Two types of aging

Chronological age counts time from when someone was born: He’s 12 years old. Biological age tells the story of how someone’s body is aging, based on measurable changes in cells, organs, metabolism and other body systems, the researchers explain.

As the difference between biological age and chronological age grew, the researchers saw that the cancer risk did, as well. “People from more recent generations tended to have larger gaps than those born earlier, suggesting their bodies appeared biologically older at the same chronological age,” per the news release.

That shift to aging faster biologically could play at least a role in the rise in cancer among younger adults, the team said.

But they also saw that the biological aging was not at a consistent pace bodywise. So when one part of the body aged faster, it affected the risk of a particular cancer. An immune system that appeared to be biologically older is an example: It was linked to early-onset lung cancer. If the fat tissue aged faster biologically, the risk of early-onset colorectal cancer was higher.

Researchers hope that measuring accelerated aging will at some point help doctors identify those younger people at higher cancer risk, which could boost early screening, as well.

“Our ultimate goal is to decode how modern environments become biologically embedded to drive cancer risk, transforming prevention from broad recommendations to personalized interventions,” said Cao. “This brings us closer to identifying risk earlier and developing prevention strategies that are tailored to an individual’s biology.”

A look at other risk factors

Cao and her colleagues had already looked at a lot of factors tied to cancer risk over time, such as obesity, metabolic conditions, alcohol use, lack of physical activity, poor nutrition and cesarean delivery. While those all provide clues about why cancer develops at younger ages, the researchers said they don’t individually explain very much about the trend toward certain cancers at younger ages.

So the team decided to look for other ways to measure the combination of different influences and how they might work together to make cancer more likely.

They looked at data from more than 154,000 young adults who were part of the UK Biobank, which has a lot of biological, health and lifestyle data on its participants.

They also looked at data from more than 10,000 U.S. participants in the National Institutes of Health’s All of Us Research Program, which hopes to create a comprehensive health database that includes more than 1 million people living in the U.S.

Deciding how fast the body ages

The researchers considered systemic aging, measuring aging in the entire body. And it looked at organ-specific aging.

For the former, the researchers used established approaches including biomarkers, as well as a score associated with age-related patterns in a person’s metabolism. As for organ aging, they looked at levels of a variety of proteins associated with specific organ systems to estimate the biological age of specific organs.

Within each birth cohort, they calculated the average difference between biological and chronological age and applied standard deviation to measure how far each group was off the overall study average.

They found members of the younger generation tended to have slightly older biological profiles than members of the older generation when researchers compared them at the same chronological age. And the difference was bigger in the U.S. data, finding participants born between 1990 and 1999 “had systemic aging that was 92% of one standard deviation higher than those born between 1965 and 1969.”

But were those biological aging differences linked to cancer? Yes, they found greater systemic aging among the younger group was linked with an 8% increased risk of early-onset solid cancers, especially lung, gastrointestinal and uterine. And for those with the most advanced systemic aging, the risk of early-onset solid cancer grew to 15% increased risk when compared to those with the least advanced aging.

That held true even after researchers accounted for inherited genetic cancer risk and for genetic susceptibility to aging faster.

The research into why cancer is happening in younger and younger people is ongoing. The researchers noted that one of their big efforts is “determining how changes in the environment, lifestyle and society may leave long-lasting biological marks on the body. Those effects could include accelerated aging as well as other signs that make some people more vulnerable to disease.”

Ultimately, researchers hope to identify those at higher risk while they are still healthy and can make changes or be screened for treatment sooner.