Cancer Rates Are Climbing in Younger Adults — Poor Diets and Microplastics May Be to Blame
A cancer diagnosis is the last thing anyone under the age of 50 expects to be hit with, but lately, this is becoming a harsh reality for many younger adults. Cases of early onset cancer — those diagnosed in adults between the ages of 18 and 49 — have been rising since the 1990s, reflecting a dire trend that health experts are scrambling to understand.
In a May 2025 study published in Cancer Discovery, researchers at the National Institutes of Health found that incidence of 14 types of cancers increased among people under 50 from 2010 through 2019. The most significant increases were seen in breast, colorectal, kidney, and uterine cancers.
What could be causing this growth in cancer rates among young people? So far, research seems to suggest that a number of factors are to blame.
A Catalyst for Cancer
While scientists haven’t yet arrived at a definite answer to explain why early onset cancer cases are rising, they’ve proposed several ideas.
In some cases, it may be lifestyle choices that increase the risk of cancer. A sedentary lifestyle characterized by little to no exercise, combined with a poor diet that includes highly processed foods, can lay the groundwork for cancer to develop.
Nearly one-tenth of cancers in the U.S. can be attributed to obesity, mostly because it leads to chronic inflammation and altered hormone levels that promote cancer growth in certain parts of the body. According to the World Health Organization, about 16 percent of adults aged 18 and older worldwide were obese in 2022, a rate that has doubled since 1990.
Read More: The Gut Microbiome Could Help Our Bodies Fight Cancer
The Link Between Microplastics and Cancer
Some factors that contribute to higher cancer risk are more or less out of one’s control. Environmental factors, such as microplastics, could be some of the main offenders in this sense. Research in recent years has exposed the prevalence of microplastics and their potential role in cancer development.
A 2025 study showed that plastic particles can accumulate in the colon, and other studies have found greater concentrations of microplastics in those with colorectal cancer than those without cancer.
As microplastics enter our systems, they can cause cell and tissue damage, inflammation, and genetic mutations. When we breathe them in, our lung cells are among the first to suffer the consequences, being susceptible to changes commonly linked with the development of cancer. Since younger generations have been exposed to single-use plastics their whole lives, they’re particularly vulnerable to the health issues that arise from microplastics.
Catching Cancer Early
Fortunately, even though early onset cancer diagnoses are rising, overall cancer mortality has been dropping for most types of cancer. Mortality rates from uterine, pancreatic, and liver cancers have been increasing, but other types like breast, kidney, and lung cancers have seen reduced mortality over the years.
Still, some cancers that appear in younger people are prone to be more aggressive than those in older adults. According to the Breast Cancer Research Foundation, breast cancers in women under 40 are more likely to result in larger tumor size and advanced tumor stage.
Even though obesity and microplastics could certainly be influencing cancer development, diagnoses may be growing common in younger people because of earlier screening and improved technology.
A study recently published in JAMA Internal Medicine suggested that early onset cancer cases are simply being caught more frequently, challenging the notion that there is an actual surge in cancer development. In recent years, several health organizations have been lowering the recommended age for cancer screenings — most now advise colorectal cancer screenings to start at age 45 (down from 50) and breast cancer screenings to start at age 40 (down from 50).
This article is not offering medical advice and should be used for informational purposes only.
Read More: Childhood Bacteria Exposure Linked to Early Cancer Risk
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