Millennials may love avocados, Fitbits, and booze-free cocktails, but that doesn’t mean they’re healthy.

In fact, their health is declining—and since they’re the largest cohort currently in the U.S. workforce, with close to 73 million people, that will have major implications for both healthcare costs and economic growth, according to a new Moody’s Analytics report prepared for the Blue Cross and Blue Shield Association, a group of 36 local Blue Cross and Blue Shield companies around the U.S.

The research found millennials’ physical and mental health is declining faster than that of Generation X. (For reference, they define a millennial as a person born between 1981 and 1996 and a Gen-Xer as someone born between 1965 and 1980.) The report cited conditions such as hypertension, high cholesterol, and behavioral health conditions, including major depression and hyperactivity, as increasing among millennial-aged Americans. And if there’s no intervention, millennials’ mortality rates could skyrocket over 40% compared to the generation immediately before them, Fast Company says.

With free-falling health comes increased healthcare costs. The data indicated that costs could jump as much as 33% compared to Gen-Xers, when the latter were at the same life stage. Those ailments will also pinch their pocketbooks in less direct ways, due to more unemployment and slower income growth. Moody’s Analytics determined that millennials could see a decrease of more than $4,500 in real per capita annual income due to health problems.