Sleep
Fifty years ago people in the West slept an average of nine hours a night. Fifteen years ago we slept eight hours a night. But now we average seven hours of sleep a night.
There is quite a lot of research quoted in this chapter because I want to convince you just how important sleep is.
A 2001 poll taken by the American National Sleep Foundation (NSF) reported that 63 percent of American adults did not receive the recommended eight hours of sleep necessary for good health, safety and optimum performance.
The research recommends we have an average of eight hours sleep every night. Clearly everyone is different and we all have slightly different sleep needs. But if you do not get the sleep you need you become sleep-deprived.
Sleep deprivation causes the following:
Fatigue
Fatigue’s consequences include higher instances of motor vehicle accidents, work- related accidents, decreased productivity and adverse health effects. Daniel O’Hearn, a Johns Hopkins University sleep disorders specialist observed, “People don’t respect sleep enough. They feel they can do more - have more time for work and family - by allowing themselves less time for sleep”.
Poor Health
A 2001 Sleep Foundation survey draws attention to several medical conditions linked directly to sleep deprivation, including depression (83 percent), night time heartburn (82 percent), diabetes (81 percent), hypertension (79 percent), and heart disease (78 percent). In addition, sleep deprivation can accelerate the aging process, lead to obesity and increase the risk of memory loss. The British Medical Association also confirmed higher levels of stress, anxiety and depression among the sleep-deprived.
Poor Wealth
According to Cornell University psychologist and sleep expert James Maas, sleep deprivation and sleep disorders cost the American economy at least $150 billion a year, as a result of decreased job productivity and fatigue-related accidents.
Sleep researcher Eve van Cauter at the University of Chicago exposed sleep- deprived students (allowed only four hours per night for six nights) to flu vaccine; their immune systems produced only half the normal number of antibodies in response to the virus. Levels of cortisol (a hormone associated with stress) rose, and the sympathetic nervous system became active, raising heart rates and blood pressure. The subjects also showed insulin resistance, a pre-diabetic condition that affects glucose tolerance and produces weight gain.
So those are the negatives of a poor sleep. What are the benefits of a good sleep? Two key benefits of having a good sleep are:
1. It Boosts Your Immune System
Researchers in Germany found that among a group of volunteers vaccinated against hepatitis A infection, those who got a good night’s sleep afterwards showed a stronger immune response to the vaccine.
2. It Improves Longevity
Sleeping well helps keep you alive longer. Among humans, death from all causes is lowest among adults who get seven to eight hours of sleep nightly, and significantly higher among those who sleep less than seven hours.
I have the type of personality that likes to push boundaries, and I like to get the most out of every day. Because of this I have often not slept enough. In my late twenties I was working hard as an accountant, plus doing tax returns for private clients, and also building up a property portfolio, so I was busy all week long. I found that in general I could get by on six hours sleep a night and could even manage the occasional night of only four hours sleep. After about a year of this I could feel my stress levels rising. Sometimes I was so stressed that when I went to bed at night I wondered (irrationally) whether I would actually wake up in the morning, or die in my sleep. I got sick often and enjoyed life less. I finally went to the doctor who quizzed me on my lifestyle. He told me I had to make changes to my lifestyle or things would get worse. I immediately cut down on the extra work I was doing and made some changes. It took about six months to get back to feeling normal and I have learned my lesson.
There was one exception. In the late 90s I was working as an accountant in London, working 50-hour weeks plus a two-hour commute every day. I knew I was getting tired and stressed but I decided (foolishly) to see how far I could push myself. So I worked longer and harder, and one day I was so tired I fell asleep at work sitting on the toilet! Soon after that I got shingles which is pretty awful, and I had to take two weeks off work (unpaid). So I found out my limit, and I paid for it. It took me about three months to get to 100% energy again.
About two years ago I made a conscious decision to get at least seven and a half hours sleep a night and more if I felt tired. The result is that I have far more energy and enthusiasm, and I get sick a lot less.
If you can’t free up any more time in your day for sleep then you need to make a lifestyle change. It might be as simple as no more TV, DVD’s and movies!
Note: See my discussion on Caffeine in the chapter “Exercise and Diet” on how caffeine intake can negatively impact your sleep.
Footnotes:
1. National Sleep Foundation “Less Fun, Less Sleep, More Work: An American Portrait.” Mar. 27, 2001.
2. FDA Consumer Magazine. “Sleepless Society” July-August 1998.
3. “Sleep Deprivation as Bad as Alcohol Impairment, Study Suggests.” CNN Health. Sept 20, 2000.
4. “National Sleep Debt is Killing Americans and Hurting Economy”, Cornell Psychologist, Jan. 19, 1998.
5. Journal of Psychosomatic Medicine Sept/Oct 2003.
6. www.harvardmagazine.com “Deep into Sleep” by Craig Lambert.