Cancer in young adults is rising — is a ‘Westernized’ lifestyle to blame?

The cancer age gap is closing — to the detriment of younger generations.

A new study has shown that young, ordinarily healthy adults are being diagnosed with cancer at worrying rates.

Researchers from Brigham and Women’s Hospital saw that more and more people under the age of 50 are being diagnosed with cancer of the breast, colon, esophagus, kidney, liver, pancreas and more — globally — in a trend that took a sharp upward turn around the year 1990.

“From our data, we observed something called the birth cohort effect. This effect shows that each successive group of people born at a later time (e.g., decade-later) have a higher risk of developing cancer later in life, likely due to risk factors they were exposed to at a young age,” said Dr. Shuji Ogino, professor of pathology and physician-scientist at Brigham and Women’s, in a press release.

“We found that this risk is increasing with each generation,” Ogino continued. “For instance, people born in 1960 experienced higher cancer risk before they turn 50 than people born in 1950 and we predict that this risk level will continue to climb in successive generations.”

Cancer is a genetic disease — it’s caused by changes in genes that lead to cell division error and tumors. Some of these genetic changes are inherited, but the new study, published in Nature Reviews Clinical Oncology, focused on environmental factors that cause damage to DNA and contribute to the cancer growth.

Cancer-causing toxins could be more rampant than people believe. There are a few well-known risks out in the world, such as high UV exposure or smoking cigarettes, while emerging research now points to second-, and even third-hand smoke — as in touching surfaces contaminated by smoke residue — as significant carcinogens, too.

When looking at the incidence of 14 types of cancers, Ogino, along with lead study author Dr. Tomotaka Ugai and their team, discovered an increasing trend of cancer presence and diagnosis prior to the age of 50.

Harmful exposures at a young age — which could point to problematic diet, lifestyle behaviors and environmental pollution — could play a vital role. Since those factors have drastically changed in the past few decades, the scientists have suggested that a “Westernized” lifestyle could be a major contributor to the development of cancer.

Alcohol consumption, smoking, obesity, eating highly processed foods and sleep deprivation are potential risk factors, much of which is on the rise around the world.

“Among the 14 cancer types on the rise that we studied, eight were related to the digestive system. The food we eat feeds the microorganisms in our gut,” said Ugai. “Diet directly affects microbiome composition and eventually these changes can influence disease risk and outcomes.”

While the team could not adequately analyze low- and middle-income countries due to insufficient data, Ogino and Ugai hope to continue their cancer research and work with international research groups going forward.