Warning: This article contains discussion of cancer which some readers may find distressing.
After years of investigation, scientists believe they may have uncovered an early clue explaining why 11 different cancers are becoming more common in younger people.
With around half of people expected to develop cancer at some point in their lives, continued research into the disease remains critical.
In the United States, close to two million new cancer diagnoses are made annually, and cancer is the second biggest cause of death, behind heart disease.
Although overall cancer mortality has been falling since the early 1990s—largely due to earlier diagnosis, fewer people smoking, and better treatments—experts have still been trying to understand why particular cancers are increasingly being seen in younger adults.
Now, a new study led by researchers at the Institute of Cancer Research and Imperial College London has shared results that could help explain the trend.
The researchers pointed to 11 cancers becoming more frequent among people in their 20s, 30s, and 40s: thyroid, multiple myeloma, liver, kidney, gallbladder, colorectal (bowel), pancreatic, endometrial (womb lining), oral, breast and ovarian cancers.
Taken together, the data suggests a wider change in cancer patterns, with diagnoses appearing earlier in life than has typically been observed in the past.
One key factor flagged by the study is obesity, which is thought to be contributing to the increase.
Obesity stands out because it is the only established behavioural risk factor that has risen in younger adults, while other major risks—such as smoking, alcohol consumption, and physical inactivity—have either held steady or decreased.
The study also estimates that keeping to a healthier weight could potentially prevent roughly 20 percent of bowel cancers, 35 percent of endometrial cancers, and 27 percent of kidney cancers.
“We cannot wait to act,” says Professor Montserrat García-Closas of the Institute of Cancer Research.
“Tackling obesity across all ages, particularly in children and young people, through stronger public health policies and wider access to effective interventions, could slow the rise in cancer and prevent many cancers – and must become a national priority.”
She added: “Although it cannot fully account for the scale of the rise in bowel and other cancers…understanding these patterns is essential for identifying what is truly driving cancer risk in today’s generations.”
If you’ve been affected by any of these issues and want to speak to someone in confidence, contact the American Cancer Society on 1-800-227-2345 or via their live chat feature, available 24/7 every day of the year.