Heart disease claims more American lives each year than all other diseases. To protect yourself from this health assassin—new research suggests it may be as simple as getting more sleep each night!

Christopher Ryan King, B.S., of the University of Chicago Medical Center, and colleagues found that one extra hour of sleep each night appears to decrease the risk of developing calcified plaque in coronary arteries (calcification). This is considered to be an early sign of cardiovascular disease.

According to an online health report, the researchers said the extra sleep was comparable to the health benefits associated with lowering systolic blood pressure by 17 mm Hg!

Your coronary arteries supply oxygen-rich blood to your heart. When plaque builds up inside artery walls, it causes them to narrow. Measuring the amount of calcium in your arteries is a tell-tale sign of how much plaque they may contain.

At the beginning and end of the study, participants had their coronary arteries scanned using computed tomography (CT). They also wore a wrist device for six days at the beginning of the study to measure their activity and to provide information on their sleep habits.

The researchers said participants averaged about six hours of nightly sleep. Very few people slept for more than eight hours per night.

CT scans administered at the end of the five-year study showed about 12 percent of participants had developed coronary artery calcification. The research team found that people who slept longer—as confirmed by their wrist monitors&mdah;were less likely to develop coronary artery plaque.