Rest assured: Sleep is good for arteries

William Atkins
Friday, 26 December 2008 01:47

Science - Health

The team also found that 12.3% of the subjects developed calcification during the five-year study.

They also found that participants who slept less than five hours each night, on average, had a 27% chance of developing calcification of the arteries.

Those sleeping between five and seven hours were at risk at only 11%. Those that slept over seven hours each night only had a 6% chance of developing artery calcification.

They conclude in the abstract to their paper, “Longer measured sleep is associated with lower calcification incidence independent of examined potential mediators and confounders.”

Dr. Lauderdale, who is an associate professor in the Department of Health Studies at the University of Chicago, stated, “We found that people who on average slept longer were at reduced risk of developing new coronary artery calcifications over five years. It was surprisingly strong. It's a very early marker of future risk.” [New Scientist (subscription required): “Skimping on sleep linked to hardened arteries”]

The research team is unsure what causes less risk from artery calcification with more hours of sleep each night.

However, they propose two hypotheses: (1) blood pressure is lower for people who sleep more and higher blood pressure increases one's risk of calcification, or (2) cortisol (a stress hormone) is less in people who sleep longer and, thus, these people are less likely to be stressed out.

They do not rule out other hypotheses, and recommend that other scientists perform similar studies to confirm their discovery.

The Lauderdale team, however, do state that many studies have shown the increased health benefits of an adequate amount and quality of sleep each night.