Every generation seems to look younger than the one before it. A 40-year-old today will look like a 40-year-old did at 30 a few decades ago. But that youthfulness might only be skin deep, according to new research suggesting that Millennials and Gen Z are aging faster than previous generations at a biological level. That accelerated aging may help explain the concerning rise in cancers among younger adults.

According to a study published in Nature Medicine and reported by ScienceAlert, researchers from the Washington University School of Medicine analyzed health data from more than 164,000 people in the United Kingdom and the United States. Instead of using a person’s chronological age, researchers measured a study participant’s biological age. That’s something we’ve covered before here on VICE, wherein researchers test blood-based markers associated with inflammation, metabolism, kidney function, and immune health to get a much more detailed sense of how a person is aging.

The results may not align with how many birthdays they’ve celebrated, either.

Scientists Say Younger Generations May Be Aging Faster at a Biological Level

The researchers found that people born more recently appeared to be biologically older than those in older generations at the same age. In the United States, participants born in the 90s had substantially higher biological age scores than those born in the 1960s. Similar patterns showed up in the UK.

With that established, the researchers looked at whether all this accelerated aging was in any way linked to cancer risk. Cancer has been on the rise among younger people in recent years. Researchers don’t know why, but perhaps the study from Washington University School of Medicine can help shed some light, as the researchers found that each increase in biological aging corresponded to an 8% risk of developing cancer before age 55. They also found elevated risks for colorectal cancer, cancers related to the digestive system, and uterine cancers.

While an exact explanation has not been settled upon, rapid biological aging could play an important role, or it could even be the culprit itself. Time will tell.

The good news is that rapid biological aging can be slowed or reversed. There is no miracle cure, as all the ways to reduce a person’s biological age are the same generalized piece of advice you get to remain healthy, including exercising, maintaining a healthy weight, not smoking, sleeping well, and eating a Mediterranean-style diet.

A lot more research is needed, but so far, the research suggests that modern lifestyles are rapidly accelerating aging, and possibly accelerating the rate at which young people develop cancers.