Experts disagree on how much sleep adults need, but it’s becoming clear that too much sleep may be just as dangerous to your health as too little.
Like diet and exercise, sleep is vital to well-being. It plays a role in regulating emotions as well as in learning and memory functions. Those who suffer from sleep disorders may experience decreased alertness, mood swings and reduced physical stamina.
Today’s common belief is that adults need eight hours of sleep per night, although experts would caution that individual needs can vary greatly. In fact, sleep research conducted at Harvard University in 2007 indicated that the optimum amount of shuteye for adults is 7.2 hours, not eight.
There are some easy ways to determine how much sleep you need personally. One is to go to bed at exactly the same time every night. After a few weeks, your body will recognize the pattern and start waking up when it has had sufficient rest.
Another way is to wake at the same time every morning, but go to bed only when you feel sleepy. Again, your body will make adjustments and begin telling you the right time to retire. You’ll most likely start sleeping less than eight hours, which can benefit you in more ways than additional waking time for work and play.
In 2008, researcher Daniel Kripke of Scripps Clinic Sleep Center told Time magazine that “people who sleep between 6.5 hr. and 7.5 hr. a night…live the longest. And people who sleep 8 hr. or more, or less than 6.5 hr … don't live quite as long.” He added that risks associated with sleeping 8.5 hours might really be a little worse than sleeping only five hours.
Of course, many cultures thrive on far fewer hours of sleep per night by taking siestas. The Harvard study indicated that Greek adults who napped regularly were 37% less likely to die of heart disease than those who skipped the afternoon snooze. Other studies affirm that power napping just 10-20 minutes a day can help increase productivity, reduce stress and even lower your nightly sleep requirement.
Alfablue, January 2013