In our culture, we tend to value the ability to function on few hours of sleep. But not getting enough sleep can lead to health problems and even shorten your life.
There are an endless number of pursuits that make us want to push our bedtime later and later, from work to Facebook to our favorite TV shows. Making a habit of skimping on sleep can have a huge impact on health and even lead to a shorter life.
Studies have consistently shown that sleep deprivation or sleeping less than five hours a night can lead to major health problems, including high blood pressure, heart disease, diabetes, obesity, cancer, and ultimately an increased risk of mortality.
“The majority of the research says that a longer sleep time is associated with better health,” says Robert Oexman, DC, director of the Sleep to Live Institute in Joplin, Missouri.
However, research also shows that people who sleep more than nine hours a night have a higher risk of dying — likely because excessive sleep and fatigue are associated with conditions such as cancer and depression that can increase mortality risk. This doesn’t mean that you’re hurting your health if you sleep a little longer than usual, especially if you’re catching up on sleep after a few late nights.
Here’s what research says about how much sleep is optimal.
How Much Sleep Do You Need?
”When you can wake up easily in the morning and stay alert throughout the day, you’re getting enough sleep,” Oexman says. “For most people, a healthy amount of sleep is seven to nine hours a night.”
Research supports that timeframe for living longer. In one analysis of 16 studies that looked at nearly 1.4 million people in total, a lack of sleep increased the risk of death.
People who regularly slept less than seven hours a night (and often less than five hours a night) were at 12 percent greater risk of dying than people who slept seven to eight hours every night, according to the study.
Another review of 15 studies found that both too little and too much sleep time increased the risk of heart disease and stroke.
Researchers believe that a lack of sleep affects hormones that may increase appetite and lower energy levels, which can lead to obesity, blood sugar problems, and cardiovascular disease. Sleep deprivation is also linked to low-grade inflammation in the body, which can contribute to cardiovascular disease as well as cancer and other conditions.
In addition to health problems, sleep deprivation can make it harder to concentrate and can increase your chances of accidental injury, notes Oexman.
On the other hand, one study presented controversial findings that got a lot of media attention. It indicated that sleeping between five and six hours a night didn’t have the negative impact associated with sleep deprivation and suggested that the belief that people need eight hours of sleep a night is incorrect. Nevertheless, the majority of the research suggests that seven to nine hours of sleep is optimal, Oexman says.
What Is Too Much Sleep?
Lack of sleep certainly can harm you, but is lengthy sleep associated with health problems too?
One study found that people who consistently slept more than eight or nine hours a night had a 30 percent higher risk of dying than people who got seven to eight hours of sleep a night.
It is not clear if excessive sleep itself is actually harmful to the body, but it is linked to a number of conditions that can increase the risk of death. People with illnesses like cancer, for instance, tend to sleep longer, Oexman says. Depression, obesity, and poor overall health can also lead to spending more hours in bed.
The results of this research don’t mean you shouldn’t allow yourself to sleep later when you’re tired. If you’re sleeping more than nine hours a night on a regular basis though, it could be a sign of depression or another health problem, warns Oexman. Be sure to discuss your sleep habits with your doctor, particularly if they’ve recently changed.
In the meantime, don’t fret about sleeping a little longer. Everyone needs a different amount of sleep to be healthy. You’re better off when you allow yourself to get enough sleep so that you feel refreshed and ready for the day.
By Marie Suszynski