Scientists say they may have found one of the first major clues explaining why several cancers are rising among younger adults. A new study by researchers from the Institute of Cancer Research and Imperial College London found that obesity appears to be strongly linked to the increase in many cancers among people aged 20 to 49 in England.
The study looked at cancer trends between 2001 and 2019 and found that 11 types of cancer had increased in younger adults. These included bowel, ovarian, thyroid, kidney, pancreatic, liver, gallbladder, oral, breast, endometrial and multiple myeloma cancers.
Researchers found that obesity was linked to 10 of the 11 cancers that were rising. This has made excess body weight one of the strongest early explanations for the trend, especially because other known risk factors such as smoking and alcohol use were either stable or declining during the same period.
Experts say obesity can affect the body in several ways that may increase cancer risk, including changes in hormones, inflammation and how cells grow. However, scientists warned that obesity does not explain everything. Other possible factors being studied include early life exposures, diet changes, ultra processed foods, gut health and environmental chemicals.
The rise in bowel cancer among younger adults has caused particular concern. Separate research has shown increasing rates of colorectal and rectal cancer in adults under 50, with some patients experiencing delays before diagnosis because symptoms are often mistaken for less serious problems.
Although cancer in young adults is still relatively uncommon, doctors say the trend is important because it may show how modern lifestyle and environmental changes are affecting long term health. Researchers are now calling for stronger prevention policies, better public awareness and more investigation into why early onset cancers are becoming more common.
Health experts say maintaining a healthy weight, eating a balanced diet, staying active and seeking medical advice for unusual symptoms can help reduce risk. They also stress that young people should not panic, but should pay attention to persistent changes in their body and speak to a health professional when something does not feel normal.
