Cancer under 50: excess weight explains only part of the rise, study finds

The rise in cancer among people under 50 can be explained only in part, according to a study published in the journal BMJ Oncology and reported by ScienceDaily on Oct. 14. A team including Montserrat Garcia-Closas and Amy Berrington de Gonzalez analyzed England's national cancer registry data from 2001 to 2019 for more than 20 cancer types. They compared adults aged 20 to 49 with those 50 and older and matched the trends against national health surveys on smoking, alcohol, diet, body weight and physical activity.

Among women under 50, 16 of 22 cancer types rose significantly, and among men 11 of 21, the study found. Eleven behavior-linked cancers became more common in younger adults, including cancers of the thyroid, liver, kidney, bowel, pancreas, breast and endometrium. Excess weight is linked to 10 of them. Most other risk factors, however, were stable or improved over one to two decades: red meat intake fell by about 7%. More than 90% of younger adults did not meet fiber recommendations in 2018.

The researchers stressed that the absolute cancer burden remains far higher in older adults. The trends likely reflect "the net effect of multiple influences operating in different directions," pointing to other contributors. The study is observational and shows associations, not cause and effect. It covers England only and did not assess factors such as reproductive history, early-life exposures or changes in screening and detection.