Faster aging may explain why more younger adults are getting cancer

Cancer is often called a disease of aging, and for good reason.

Older adults tend to face higher cancer risk because they’ve had more time to accumulate the cellular damage that can trigger tumor formation.

But over the past several years, cancer rates have been rising in younger adults, defined usually as age 55 and under.

According to the American Cancer Society, people younger than 50 were the only age group to experience a sustained increase in cancer incidence from 1995 through 2021.

That has prompted researchers to ask an unsettling question:

Could cellular damage be accumulating faster in more recent generations, causing their bodies to age biologically faster?

A study led by researchers at Washington University School of Medicine in St. Louis suggests that this may be the case — and may help explain why more young adults are being diagnosed with cancer.

Younger generations may be aging faster biologically

The researchers wanted to know whether the gap between a person’s chronological age and biological age could help explain early-onset cancer risk.

Chronological age is the number of birthdays you’ve had. Biological age reflects how old your body appears to be on the inside — based on blood markers, metabolism and signs of wear and tear across different organ systems.

In other words, two people can both be 45. But one may have a body that looks biologically younger, while the other shows signs more typical of someone older.

To investigate, the team analyzed data from more than 154,000 young adults in the UK Biobank and more than 10,000 U.S. participants in the National Institutes of Health’s All of Us Research Program.

They looked at biological aging in two ways: systemic aging across the body as a whole, and organ-specific aging within individual tissues and systems.

What they found suggests younger generations may be carrying older biology than earlier generations did at the same age.

In the UK data, people born between 1965 and 1974 showed more advanced systemic aging than those born between 1950 and 1954, even after accounting for chronological age.

The same pattern appeared in the U.S. data. Participants born between 1990 and 1999 showed more advanced systemic aging than those born between 1965 and 1969.

The shift was subtle — not a sign that younger adults suddenly looked decades older on paper. But it was clear enough to raise concern: People born more recently tended to show older biological profiles than people born earlier, when compared at the same chronological age.

Faster aging was linked to higher cancer risk

Next, researchers looked at how those aging patterns lined up with cancer risk.

Early-onset cancers are generally defined as cancers diagnosed at age 55 or younger. That’s slightly different from some cancer statistics that focus on adults under 50, but it reflects the definition used in this research.

In the study, increased systemic aging was associated with an 8 percent increased risk of early-onset solid cancers, especially lung, gastrointestinal and uterine cancers.

And when researchers divided participants into three groups based on their level of systemic aging, those with the most advanced aging had a 15 percent higher risk of early-onset solid cancer compared with those with the least advanced aging.

Importantly, that higher risk remained even after researchers accounted for inherited genetic cancer risks and genetic susceptibility to accelerated aging.

That suggests faster biological aging may be capturing something broader than inherited risk alone.

The organ-specific findings were especially interesting.

Advanced immune system aging was linked with a higher risk of early-onset lung cancer.

Advanced aging in adipose tissue — or fat tissue — was linked with a higher risk of early-onset colorectal cancer.

That matters because it suggests cancer risk may not be driven only by changes inside individual cells. It may also be influenced by wider biological changes happening across the body.

“Our ultimate goal is to decode how modern environments become biologically embedded to drive cancer risk, transforming prevention from broad recommendations to personalized interventions,” says Dr. Yin Cao, a molecular epidemiologist and associate professor at WashU Medicine. “This brings us closer to identifying risk earlier and developing prevention strategies that are tailored to an individual’s biology.”

What’s making younger bodies age faster?

Researchers still don’t have a definitive answer.

But they’re looking closely at how environmental, lifestyle and societal changes may leave lasting biological imprints — including accelerated aging and other markers of higher cancer susceptibility.

That makes sense because many factors already tied to early-onset cancer also overlap with factors linked to faster aging.

These include poor diet quality, obesity, metabolic problems, alcohol use, sedentary behavior and other modern exposures that can place stress on the body over time.

“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,” says Dr. David Scott, director of Cancer Grand Challenges.

The hope is that measures of accelerated aging could someday help identify younger people at higher risk while they’re still healthy — giving doctors a better chance to focus on prevention and early detection.

That could shift cancer prevention away from one-size-fits-all advice and toward strategies tailored to a person’s biology.

How to protect your biological age

For now, there is no single test or supplement that can erase cancer risk or guarantee slower aging.

But the good news is that many of the habits that support healthier aging are the same ones already linked to lower cancer risk.

That means the basics still matter:

● Eat a nutrient-rich diet that emphasizes vegetables, fruits, fiber, healthy fats and quality protein.

● Stay physically active for significant impacts on aging, and avoid long stretches of sitting when possible.

● Support healthy blood sugar and insulin sensitivity.

● Maintain a healthy weight, especially around the waistline.

● Limit alcohol. Research shows it strongly impacts aging.

● Prioritize sleep, since poor sleep can affect metabolism, inflammation and immune function.

● Avoid tobacco and reduce exposure to pollutants when you can.

Vitamin D may also deserve attention…

Separate research has found that vitamin D3 may slow biological aging by slowing telomere shortening, a marker of cellular aging. Other research has also indicated that vitamin D status is connected to cancer risk.

When it comes to holding onto your health, being proactive matters. Start today.

Sources:

Faster aging in younger generations linked to rise in early-onset cancer — WashU Medicine

Biological aging and generational shifts in early-onset cancer risk — Nature Medicine

Cancer statistics, 2025 — CA: A Cancer Journal for Clinicians

FAQ: Early-onset cancer and biological aging