Category Archives: Amount of Sleep

Can I Sleep Too Long? Not if You Exercise

In the field of sleep medicine there has been a great deal of controversy as to whether or not it is unhealthy to sleep for too long. Numerous studies have been published showing short sleep duration to be associated with hypertension, diabetes, and premature death. However, in several studies, long sleep as defined by sleeping greater than eight hours has also been associated with premature death. This has become a source of debate, as its basis has been hard to explain. In a study published this month in the American Journal of Epidemiology titled Sleep Duration and Survival Percentiles Across Categories of Physical Activity, I believe we finally have an answer.

This was an extensive study performed in Sweden during a 15-year period. Over 75,000 men and women were followed regarding death. They were divided based on their sleep duration and level of activity. Those who slept less than six hours a night were defined as short sleepers and those who slept greater than eight hours were defined as long sleepers. Individuals who slept around seven hours were in the majority and defined as normal. A low level of activity was defined as those who walked or bicycled less than 20 minutes per day, had sedentary work/occupations, and spent most of their leisure time doing such things as watching television. Higher levels of activity were defined by increased walking, biking, non-sedentary occupations, and exercising regularly.

The researchers found that short sleepers, regardless of physical activity, had a much higher incidence of death when followed over 15 years, than did normal sleepers. However, in the long sleeper group, those that slept greater than eight hours, physical activity was the most important factor in predicting early mortality. In those that slept greater than eight hours, shorter survival was seen only in those with the lowest levels of physical activity.

The major causes of death in all groups were cardiovascular disease and cancer. In long sleepers, a lack of physical activity predicted cardiovascular causes of death such as heart attack and stroke, but not cancer.

What is the take home message of this important study? First, it once again reveals that those of us who get less than six hours of sleep are at increased risk for early death even if we are active and exercise regularly. Second, it finally seems to answer the age-old question of “can you sleep too much?” It would appear that the answer is no, not if you maintain a reasonable level of physical activity.

Snoozing or Losing? How the Snooze Button Affects Your Sleep

I am often asked by my patients if it is okay to keep hitting the snooze button for those extra zzzz’s. They want to know if it is beneficial or detrimental. My answer is “ask yourself why do you need to do that and does it really make you feel better”? In reality, it may not only be a sign of inadequate or poor quality sleep, but it can make functioning during the day even more difficult.

In many instances, you may be suffering from what we call social jet lag. You sleep much longer on weekends but on weekdays, given the pressure of a job or family, you can’t. Hitting the snooze alarm is a fruitless effort to obtain the sleep that you really need.

When you hit the snooze alarm, you are disrupting your current stage of sleep. Unfortunately, in many ways, fragmented sleep is worse than no sleep. As an example, if you are in REM sleep and you interrupt it with the snooze alarm, this can lead to an inability to process and reconcile emotionally laden memories from the previous day. In addition, fragmented sleep can result in moodiness, cognitive problems, and trouble paying attention.

What can we do to avoid this? First, we must realize that in many cases our body is telling us that we are not getting enough sleep. Try going to bed one-half hour earlier. Turn off all blue light emitting devices at least one hour before bedtime. Blue light delays the production of melatonin that results in lingering amounts of the sleep hormone in your blood stream upon awakening. Is it any wonder you can’t wake up?

Other remedies include putting the alarm clock where you cannot reach it; using alarm clocks that work by putting out ever-increasing amounts of light as wake-up time approaches; having a coffee maker with a timer set for ten minutes before wake time and close enough so that you can smell it. Even getting a device that can automatically increase your bedroom temperature about one hour before it is time to get up can be helpful, as rising body temperature is another signal to wake up.

The bottom line is that if you chronically find the need to hit the snooze alarm, something is probably wrong. You may be out of sync with your internal circadian clock. You may be a night owl trying to keep the work schedule of a morning lark. You may be someone who is failing at attempting to burn the candle at both ends. Alternatively, you may have a sleep disorder that unbeknownst to you is disrupting and depriving you of quality sleep. Hitting the snooze button is a poor substitute for healthy sleep.