"Study Forecasts Potentially Alarming Cancer Rates Among Generation X"

People in Generation X could have higher rates of certain cancers as compared to their parents, a new study predicts.

The study, published in June in JAMA Network Open, used statistical models to predict how common cancer cases might be for Generation X (Gen X)—people born between 1965 and 1980—once they reach their 60s.

As compared to their Silent Generation and Baby Boomer parents (including those born between 1936 and 1960), Gen X is generally expected to see higher cancer incidence, the study found.

It’s important to note that the results of the study are only predictive based on current trends rather than set in stone.

“What we try to do in a descriptive study is determine where rates are going up unexpectedly,” study author Philip Rosenberg, PhD, a biostatistician in the Division of Cancer Epidemiology and Genetics at the National Cancer Institute, told Health.

However, the findings indicate that, without some sort of change, “cancer incidence in the U.S. could remain unacceptably high for decades to come,” the study authors wrote.

To get a clearer picture of what cancer trends might look like in Gen X in the coming years, Rosenberg and his colleague looked at cancer data from 3.8 million people in the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) program. The researchers looked at cancer incidence for Gen X and for previous generations of people born between 1908 and 1964.

They looked at actual older generations’ cancer rates once they reached their 60s and then projected what cancer diagnoses could look like for Gen X once they reach that age threshold, starting as early as next year.

The data showed that while Baby Boomers were less likely to develop cancer than their parents, the same likely won’t be true for Gen X—in all demographic groups except Asian or Pacific Islander men, people born between 1965 and 1980 are projected to have a higher cancer incidence than the previous generation.

The study also further compared rates of specific cancers between Baby Boomers and Gen X in particular. The latter group is predicted to see decreases in cervical cancer and lung cancer—driven by widespread cervical cancer screening and lower rates of smoking, Rosenberg said. Gen X men may also see fewer cases of gallbladder and liver cancers.

However, these declines may be offset by rises in other types of cancer.

The biggest increases in both Gen X men and women are expected to be in thyroid cancer diagnoses, followed by kidney cancer and rectal cancer. Both groups are also expected to see higher rates of colon cancer and leukemia.

Gen X women are projected to have higher rates of uterine, pancreatic, and ovarian cancers, as well as non-Hodgkin lymphoma. Men are expected to see an increase in prostate cancer.

“These findings are not surprising, they actually confirm other studies,” Otis Brawley, MD, professor of oncology and epidemiology at Johns Hopkins University School of Medicine, told Health.

Early-onset cancer, which occurs in people under 50, has been on the rise since the 1990s. Other research has found gastrointestinal cancers, including colorectal and pancreatic cancer, are being diagnosed more often in these younger adults.

People’s genes are relatively similar across generations, Bryan Haugen, MD, professor of medicine specializing in thyroid cancer at the University of Colorado Anschutz Medical Campus, told Health.

That means differences in cancer trends over time can help researchers understand how different generations’ lifestyles—including exposures to cancer-causing agents such as chemicals or foods—may affect public health.

“It’s not that any generation is more susceptible to cancer, but rather the constellation of risk factors surrounding them,” Rosenberg said. “Figuring the whole picture out is a really important effort.”

For example, people born in the first couple decades of the 20th century had extremely high rates of lung cancer—not coincidentally, smoking was a cultural norm in the U.S. during this period.

Similarly, this research indicates that something about younger adults’ environment or lifestyle is contributing to this increased cancer incidence. Living a more sedentary life and having higher rates of obesity are two potential factors, Brawley said.

“Obesity is about to surpass tobacco as the leading cause of cancer,” he said. Diet is likely playing a role, as younger generations typically eat a more caloric diet with fewer fruits and vegetables, Brawley added.

This may go hand-in-hand with a changing microbiome.

“Our stool flora has changed due to overuse of antibiotics and some antibiotics in food,” Brawley said. “This may have led to increases in several cancers, colon among them.”

Researchers are looking into how environmental exposures to forever chemicals and microplastics might be driving rises in certain cancers among younger generations.

The projective study can only be applied to Gen X, Rosenberg said, but trends suggest Millennials would have at least as many, if not more, cancer cases than Gen X.

People of all generations can take action to avoid some of these cancer risks, including getting certain vaccines, maintaining a healthy weight, avoiding tobacco and alcohol, using sunscreen, and getting recommended screening tests.

However, this projected increase in cancer cases for Gen Z is likely caused by a number of factors, Haugen said, both in and outside of people’s control.

For example, the risk of thyroid cancer “seems to be a combination of the environment and a person’s genetics,” he said. “There’s no one thing that seems to make people get thyroid cancer and others not.”