A steep rise in obesity over the past four decades may have increased the cancer risk for younger Americans, a new report led by the American Cancer Society says.
The study — which analyzed 20 years of data (covering 1995 to 2014) for 30 cancers in 25 states — found incidences of obesity-linked cancers to be rising at faster rates in millennials than older U.S. generations.
The American Cancer Society believes this shift could impede the progress recently made in battling cancer.
“Although the absolute risk of these cancers is small in younger adults, these findings have important public health implications,” said Ahmedin Jemal, ACS’s scientific vice president of surveillance & health services research and an author of the paper.
“The future burden of these cancers could worsen as younger cohorts age, potentially halting or reversing the progress achieved in reducing cancer mortality over the past several decades.”
The study says that six of 12 obesity-related cancers — colorectal, uterine, gallbladder, kidney, pancreatic and multiple myeloma — are on the rise, particularly in people under 50, which was also published in The Lancet Public Health. Worryingly, the risk of colorectal, uterine and gallbladder cancers has also doubled for millennials compared to baby boomers when they were the same age.
Excess body weight is a known carcinogen, the American Cancer Society adds, and younger people are experiencing obesity earlier and for more prolonged periods of their lives. Of course, obesity is only one factor — the environment, genetics and other issues also play roles, the BBC points out. Not everyone who gets these cancers is overweight either, and not everyone who is obese will necessarily get these cancers.
Despite the findings, it’s not all bad news on the cancer front: the study shows that rates have declined or stabilized in all but two of 18 non-obesity related cancers, including smoking-related and infection-related cancers.