New research finds six major cancers rising in adults of all ages, challenging old assumptions
Six obesity-linked cancers—leukemia, thyroid, breast, endometrial, colorectal, and kidney—are rising in both younger and older adults across nearly three-quarters of countries worldwide, according to new research published in the Annals of Internal Medicine.
Independent reported that this global trend challenges the long-held belief that certain malignancies are confined to younger populations, signalling a shift in the landscape of cancer risk and prevention.
Researchers, including those from Imperial College London, analysed cancer incidence data spanning 2003 to 2017 from 42 countries across Asia, Europe, Africa, North and South America, and Australasia.
Drawing on the International Agency for Research on Cancer’s GLOBOCAN database, they focused on 13 cancer types previously identified as increasing among younger adults.
By segmenting patients into younger (20–49 years) and older (50 and above) cohorts, the study revealed that obesity-driven carcinogenesis is not limited by age, but is affecting adults broadly.
The study underscores the role of obesity in cancer development.
Increased fat tissue can induce inflammation, alter hormone levels, disrupt cell metabolism, and foster a pro-carcinogenic environment.
Uterus and kidney cancers demonstrated the strongest associations with obesity, highlighting how adipose tissue acts as both an energy store and a hormone production centre.
Dysregulated hormone secretion can accelerate tumour risk by increasing cell proliferation and impairing the removal of dead cells.
While the incidence of liver, oral, food pipe, and stomach cancers is declining among younger adults—likely due to successful public health interventions targeting tobacco, alcohol, and viral hepatitis—gut cancer rates are climbing more rapidly in younger adults than in older ones.
The researchers suggest this may reflect more effective screening in older populations, while younger adults may be increasingly exposed to new environmental or dietary carcinogens.
The findings highlight the need for tailored research into the causes of cancer subtypes across age groups.
The researchers conclude, “These findings can help inform future research and clinical and public health guidelines.”
