The short answer
Some cancers are becoming more common in adults under 50. A 2026 study found that people in younger generations tend to show faster biological aging, and that faster aging was linked to a somewhat higher chance of cancer before age 55. The study shows a link, not a cause. Knowing screening ages and getting new or lasting symptoms checked still matters most.
NCI reports that colorectal, breast, uterine, and kidney cancers are among those rising most in people under 50.
A 2026 Nature Medicine study found that younger birth groups showed faster biological aging than older ones at the same age.
Faster biological aging was linked to about an 8% higher risk of solid cancers before age 55, per step up on the aging scale.
The study shows a link, not proof that aging causes these cancers, and it does not say what speeds aging up.
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The whole article, with every detail and caution.
The simple version
Some cancers are showing up more often in adults under 50. The National Cancer Institute (NCI) calls these early-onset cancers. NCI reports that colorectal, breast, uterine, and kidney cancers show some of the biggest rises. Fourteen cancer types went up in at least one age group under 50 between 2010 and 2019.
A common belief is that cancer is only a disease of older people. Age is still a major factor, but young adults can and do get cancer.
No single cause has been found. Researchers think many factors likely work together.
What researchers are looking at
NCI says genes alone cannot explain the rise. Scientists are studying things like:
- obesity and alcohol use
- changes in the gut microbiome (the germs that live in your gut)
- toxins made by some strains of E. coli bacteria that can damage DNA
- microplastics
- a "birth cohort effect," meaning people born in later years may share exposures that build up over time
What the biological-aging study found
In June 2026, a team led by Yin Cao at Washington University School of Medicine in St. Louis published a study in the journal Nature Medicine. It asked a new question: are younger generations aging faster on the inside?
Your biological age is an estimate of how old your body seems, based on blood tests. It can be older or younger than your real age. The team used several aging clocks, which are research tools that turn lab results into an age estimate.
They studied more than 154,000 young adults in the UK Biobank and more than 10,000 people in the US All of Us Research Program. Here is what they reported:
- Younger birth groups aged faster. In the UK group, people born in 1965 to 1974 showed more biological aging than people born in 1950 to 1954 at the same age. The university says the US group showed an even larger gap between people born in the 1990s and those born in the late 1960s.
- Faster aging was linked to more early cancer. Each step up on one aging scale was tied to about an 8% higher risk of solid cancers before age 55. People with the fastest aging had about a 15% higher risk than those with the slowest.
- Some organs stood out. Signs of immune system aging were linked to early lung cancer. Signs of fat tissue aging were linked to early colorectal cancer.
The study adds a possible piece to the puzzle. It does not solve it.
What the study does not show
The authors are clear about limits:
- It is an observational study. It shows a link, not that faster aging causes cancer.
- It does not say what makes people age faster. The university says that is still under study around the world.
- Aging clocks have not been well tested in young or diverse groups.
- The US group was followed for only about 2.4 years on average.
- Most people studied lived in the UK or US.
It also does not mean anyone should buy a biological age test to check for cancer. These are research tools.
Screening ages to know
Screening means testing for cancer before there are symptoms. The US Preventive Services Task Force (USPSTF) recommends these starting points for people at average risk:
- Cervical cancer: start at age 21. See cervical cancer screening.
- Breast cancer: mammograms every 2 years for women ages 40 to 74. See breast cancer screening.
- Colorectal cancer: start at age 45. In 2021 the USPSTF lowered this from 50. See colorectal cancer screening.
Some people may need to start earlier, such as those with a strong family history. Your healthcare team can tell you what fits you. Our screening by age page has more.
Early signs to know
NCI says these symptoms are most often caused by something other than cancer. Only a doctor can tell. Signs NCI lists include:
- a lump or swelling, or changes in the breast
- blood in your stool, or a lasting change in bowel habits
- blood in your urine or trouble passing urine
- bleeding or bruising with no clear reason
- a cough or hoarse voice that does not go away
- trouble swallowing
- weight loss or gain you cannot explain
- fever or night sweats with no clear reason
- tiredness that does not get better with rest
- a sore that does not heal, or a new or changing mole
For early-onset colorectal cancer, NCI highlights rectal bleeding, belly pain, diarrhea, and iron deficiency anemia (low iron in the blood).
If it's new or lasts, get it checked. NCI says to see a doctor if symptoms do not get better after a few weeks. Being young is not a reason to wait. Read more in early-onset cancer in young adults.
If you have heavy bleeding, chest pain, trouble breathing, or feel you might pass out, call 911 or go to the nearest emergency room.
Common questions
What is early-onset cancer?
NCI uses the term for cancers found in people younger than 50. The 2026 aging study used a cutoff of age 55. Both describe cancer that shows up earlier in life than usual.
What is biological aging?
It is an estimate of how old your body seems based on blood tests, not on your birthday. Two people who are both 40 can have different biological ages. Researchers use tools called aging clocks to measure it.
Does this study mean aging causes cancer in young people?
No. The study found a link between faster biological aging and early cancer. It was an observational study, so it cannot prove cause and effect. The authors say other factors may play a role.
Can I get my biological age tested to check my cancer risk?
The study used research tools. It does not show that these tests can be used to find or predict cancer in one person. Ask your healthcare team about your own risk.
Should I start screening early because I am young?
Screening ages in this article are for people at average risk. Some people, such as those with a strong family history, may need to start earlier. Only your healthcare team can say what fits you.
Am I too young for my symptoms to be cancer?
Most symptoms are caused by other problems. But young adults can get cancer. NCI says if symptoms do not get better after a few weeks, see a doctor.
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Last updated: 2026-09-27Next planned review: 2028-09-26
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Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes, and this is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Source checked — This page was written with AI assistance and then compared with the sources listed on it, looking for statements those sources do not back up. That check is not a sentence-by-sentence record and can miss errors. It is not a medical review, and it does not confirm the page is complete or right for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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