UPI reports 35% of Americans get 'poor' or 'fair' sleep, and one in five say they don't wake up feeling refreshed.
According to researchers from the University of California - Berkeley, that's putting those Americans at increased risk for heart disease.
Atherosclerosis, or hardening of the arteries, is caused by chronic inflammation.
It's believed to be the underlying cause of roughly half of all cases of heart disease -- and all heart disease-related deaths -- worldwide.
Sleep loss has been linked with chronic inflammation in multiple studies.
The connection may be that fragmented sleep increases inflammation, which in turn raises a person's risk for atherosclerosis and stroke.