For the first time in decades, life expectancy for Americans has decreased.
According to new data from the Centers for Disease Control and Prevention, the overall life expectancy for the U.S. population dropped from 78.9 years in 2014 to 78.8 years in 2015.
That might seem like a pretty small difference on paper. But it has researchers worried about Americans' health and well-being.
As one expert told NPR, "This is a big deal. There's not a better indicator of well-being than life expectancy ... It's remarkable. There are lots of things about this that are unexpected."
Another expert told NPR the decrease could be a one-time thing and that more data analysis is needed.
Scientists believe a spike in 8 of the top 10 leading causes of death are to blame. These include heart disease, chronic lower respiratory diseases, stroke, diabetes, kidney disease, unintentional injuries, Alzheimer's disease and intentional self-harm.
It's unclear exactly what's behind this increase in fatalities. But at least one major cause of death saw a decline in 2015 — cancer.