Protect Your Blood Pressure by Getting Plenty of Z's

Those nights spent tossing and turning may wind up doing more than making you grouchy the next morning. Getting too little sleep may also increase your changes significantly of having high blood pressure.

Public-health experts at Columbia University in New York City say their 10-year study of 4,800 people shows that folks 32 to 59 who got five hours of sleep a night or less were 60 percent more likely to develop high blood pressure than people who dozed six to eight hours.

The results were the same even after researchers figured in depression, alcohol consumption, smoking pulse rate, obesity, diabetes and other factors that could affect sleep quality.

Furthermore, lack of sleep in younger people is more closely associated with obesity than in people over 60.

"Sleep allows the heart to slow down and blood pressure to drop for a significant part of the day," says James Gangwisch, the study's lead author and postdoctoral fellow at Columbia's School of Public Health. "However, people who sleep for only short durations raise their average 24-hour blood pressure and heart rate. This may set up the cardiovascular system to operate at an elevated pressure."

Less exercise, higher BMIs

Researchers say that little sleep leads to obesity by affecting insulin sensitivity and enzymes that control appetite. What's more, short sleep duration is linked to irritability, impatience, pessimism and stress factors that may affect people's ability to follow healthy diets and exercise.

Indeed, when compared to people who got a good night's sleep, folks who sleep five or fewer hours a night exercise less and are more likely to have higher body mass indexes. They also are more likely to have diabetes, depression and daytime sleepiness, researchers say.

However, researchers are still trying to establish a link between lack of sleep and high blood pressure in people 60 to 86. Gangswisch says people with high blood pressure, obesity and diabetes are less likely to live that long, or if they do, having trouble falling asleep just comes with old age.

"This study suggests that sleep duration may contribute to hypertension, but the magnitude of the association is modest compared to dietary factors, especially being overweight, the main driver for hypertension," says Dr. Meir Stampfer, epidemiology chairman at the Harvard School of Public Health.