An analysis released Monday by the American Cancer Society (ACS) reveals that obesity-linked cancers are on the increase among young adults in the U.S., a trend which could stifle the progress made in reducing cancer mortality over the last few decades.
Cancers related to obesity are on a steep rise among millennials, a new study by the American Society has found. Researchers warned that in six out of 12 obesity-related cancers (colorectal, uterine, gallbladder, kidney, pancreatic, and multiple myeloma), the number of cases went up in people under the age of 50. He is scientific vice president for surveillance and health services research at the American Cancer Society.
However, for nearly all (16 out of 18) of the non-obesity related cancers, except for gastric cancer and leukemia, cancers dropped or stabilized in successively younger generations-meaning the absolute risk of all cancers is lower for the youngest age groups. Read the full story from Axios.
For example, pancreatic cancer rates increased, on average, by less than 1 percent per year among people ages 40 to 84; but rates increased 2.5 percent among people ages 30 to 34 years old; and 4.3 percent per year among those ages 25 to 29. Of course, obesity is only one factor - the environment, genetics and other issues also play roles, the BBC points out.
The study, conducted by QIMR Berghofer Medical Research Institute, aimed to quantify the proportion of cancer cases that would be potentially avoidable if the prevalence of overweight/obesity and inactivity could be reduced in Australia.
But the researchers conclude that their findings have significant public health implications, particularly for health care providers and policy makers, and provide a stepping stone for future research on the relationship between the present obesity epidemic and early onset cancer. Not everyone who gets these cancers is overweight either, and not everyone who is obese will necessarily get these cancers.
The researchers note that they were not able to quantify the impact of new modes of detection - such as highly sensitive diagnostic imaging - on emerging cancer incidence trends in young generations. The study does not provide evidence of a causal relationship between obesity and cancer.
Still unexplained, however, is why the six other forms of cancer classified by the UN's International Agency for Research on Cancer (IARC) as related to obesity did not also show similar rates of increase among younger adults.
As for gastrointestinal cancer and leukemia, the researchers hypothesize that increases in autoimmune disease, antibiotic use, and exposure to environmental carcinogens may be to blame.
The findings are based on 20 years of data (from 1995 to 2014) for 30 cancers in 25 states; the data was obtained from the Cancer in North America database of the North American Association of Central Cancer Registries.
 For incidence rates and frequencies for all cancer types examined in the study, please see Table S2 the appendix.