Eight hours. That's the nightly sleep recommendation you hear most frequently, the gold standard for a healthy sleep routine. But what if it isn't? I read this article in the Wall Street Journal with great interest, for it points to recent research that suggests the eight-hour model may not be the ideal one for most healthy adults.
Although eight hours is the number most often associated with a full night's sleep, sleep experts know that there is some degree of variation when it comes to individual sleep needs. Most often, the recommendation for sleep times comes in a range of seven to nine hours, depending on the individual. The National Sleep Foundation currently recommends this seven- to nine-hour range as ideal for healthy adults.
But there is a growing body of research that suggests the ideal amount of sleep may in fact be at the very low end of that range. A number of studies indicate that seven hours -- not eight -- may be the most healthful amount of nightly sleep. There's no broad consensus about this among sleep experts -- but there's an increasingly compelling case that's being made by studies that for many people, eight hours may be more sleep than they need, or than that's healthy for them.
We hear a lot more about the dangers of too little sleep, but sleeping too much can be hazardous to your health as well. Both too little sleep and too much sleep are associated with greater mortality risks. So understanding as much as we can about the overall "best" amount of sleep has real importance.
The National Sleep Foundation is currently at work examining and analyzing sleep data in preparation to release new guidelines for sleep. And the Centers for Disease Control has funded a panel to explore all manner of issues related to sleep, including updated recommendations for healthy sleep amounts. Both are expected to release their recommendations in 2015.
Those guidelines are important, for medical professionals and the general public. But the right amount of sleep is always going to be a personal and individual determination. The most important information in determining your sleep needs is what your body and mind tell you. Pay attention to how much (and how well) you're sleeping at night, and also pay attention to how you feel during the day. A sufficient night of sleep should leave you feeling alert and energized throughout the bulk of the day, and ready for bed at roughly the same time every night.
In order to read your body's need for sleep, it's important to practice good sleep hygiene. That includes consistent bed times and wake times, a dark, cool, and comfortable bedtime, and quiet time away from bright light and electronics in the hour before bed. Give yourself ample time for sleep, and create a sleep-friendly environment and routine, and your body can tell you a great deal about how much sleep you need.
Michael J. Breus, PhD
The Sleep Doctor