Sleep and energy: what’s in a good night’s sleep?

Posted by Liz on Jan 14, 2011 in sleep disturbance, weight | 0 comments

Did you know that a lack of sleep adds up to a whole lotta energy? For the first time ever, scientists have quantified how much energy we lose when we lose a full night’s sleep…and how much we save when we get the required 8 hours.

I’ve written about sleep, aging and menopause often on Flashfree, and the outlook isn’t great. In fact:

• Difficulty falling asleep appears to be associated with menopausal symptoms in general, stress, and lower stress hormone levels.
• Awakening during the night appears to be associated with age, being late in the menopausal transition (before moving into full-blown menopause), having had early menopause, hot flashes, depressed mood, joint pain and stress.
• Early morning awakening appears to be associated with age, hot flashes, depressed mood, anxiety, joint pain, stress, and lower estrogen/higher fallopian stimulating hormone (FSH)  levels.

Now, researchers are saying that a night’s sleep actually depletes the body of energy while getting 8 hours of sleep conserves it.

In a very small study, 7 young adults were asked to stay in bed and consume a carefully regulated diet comprising of 30% fat, 50% carbohydrates and 20% protein During the study period,  they had 8 hours of sleep, followed by two days of sleep deprivation (40 hours total) followed by another 8 hours of sleep.

Compared to a typical 8 hours sleep, losing a night’s sleep actually increased the amount of energy expended by as much as 7%. This is equivalent to about 135 calories (i.e. two slice of bread) or walking about two miles. In contrast, getting a normal nights sleep actually saved almost as much energy.

Hence, it appears that sleep deprivation is a waste of energy, literally! And while it may generate some returns in terms of immediate weight loss, other researchers have shown that over time, sleep deprivation actually impairs functioning and leads to weight gain.

So, what’s in a good night’s sleep? Apparently, sleep provides a means by which we are able to conserve enough energy to support other important functions that we need to survive. However, the challenge lies in that magic 8 hours, which appears to be constantly interrupted during the menopausal period. If only we could put that energy to good use and figure out the answer to this particular dilemma that plagues us as we age.

Any thoughts?