[Level 1: Survival]
Russell Foster is a circadian neuroscientist that studies the sleep cycles of the brain. He says that, statistically, the average human spends 36 percent of his or her life asleep. Yet Margaret Thatcher once famously said, “Sleep is for wimps.” It’s as if sleep is an illness or an enemy.
The brain does not shut down while sleeping. In fact, some parts of the brain are more active while we are sleeping than when we are awake.
Why do we sleep? Interestingly, there is very little consensus among scientists when answering this question. Here are just two of many possible reasons for sleeping:
Restoration. There are numerous genes that are associated with restoration and metabolic pathways, and these genes are only turned on while sleeping. The neural connections required for problem-solving and creative thinking seem to be strengthened during sleep.
Brain processing and memory consolidation.
Our ability to solve complex problems is significantly enhanced following sleep. Some research indicates that sleep gives you a threefold advantage and enhances creativity.
Foster says that most of us are sleep deprived. In the 1950s, most people were getting approximately eight hours of sleep a night. Now we sleep an average of six and a half hours. Teenagers need an average of nine hours of sleep but often only get five. Shift workers make up 20 to 30 percent of the population (depending on which part of the world), and the body does adapt somewhat to shiftwork, but never fully. The body is hardwired to want to sleep when it is dark and to be awake when it is light. Therefore, the quality of sleep for shift workers is probably going to be poor. The same is true for people suffering from jet lag. And these sorts of situations, Foster says, lead to involuntary sleep, or what is referred to as microsleep.
Research indicates that approximately 31 percent of drivers will microsleep at least once in their lives. In the United States, research indicates that 100,000 car accidents per year were related to sleep deprivation.
In his TED talk, Foster explained, “So when you’re tired, and you lack sleep, you have poor memory, you have poor creativity, you have increased impulsiveness, and you have overall poor judgment.”
When the brain is tired, it craves stimulants, such as caffeine. There is also a strong link between lack of sleep and weight gain. If you sleep less than five hours per night, you have a 50 percent chance of being obese. Lack of sleep causes the brain to crave carbohydrates, specifically sugar.
In addition, Foster connects a lack of sleep to stress. In simple terms, tired people are stressed people. Sustained stress is an even bigger problem because it inhibits the body’s immune system. Increased levels of stress also cause higher levels of glucose in the body, Foster warns, which can result in glucose intolerance. This, in turn, can lead to diabetes. Stress also raises blood pressure, increasing the risk of cardiovascular disease.
Foster gives advice on how to get high-quality sleep (what he calls “sleep for dummies”). Below is a paraphrased summary:
- Make your bedroom a haven for sleep. It should be as dark as possible and slightly cool. Light increases levels of alertness, so you should reduce exposure to bright light for approximately thirty minutes before sleep.
- Minimize the consumption of caffeine after lunch.
- Seek out morning light. The body uses morning light to adjust its circadian clock.
Foster also debunks some myths:
Myth #1: Teenagers are lazy. No. Poor things. They have a biological predisposition to go to bed late and get up late, so give them a break.
Myth #2: We need eight hours of sleep a night. That’s an average. Some people need more. Some people need less. And what you need to do is listen to your body. Do you need that much or do you need more? Simple as that.
Myth #3: Old people need less sleep. Not true. The sleep demands of the aged do not go down. Essentially, sleep fragments and becomes less robust, but sleep requirements do not go down.
Myth #4: The fourth myth is, “early to bed, early to rise makes a man healthy, wealthy and wise.” Well that’s wrong at so many different levels. There is no evidence that getting up early and going to bed early gives you more wealth at all. There’s no difference in socioeconomic status. In my experience, the only difference between morning people and evening people is that those people that get up in the morning early are just horribly smug.
Finally, Foster links sleep and mental well-being: “We’ve known for 130 years that in severe mental illness, there is always, always sleep disruption.”
In addition, he refers to studies indicating that “sleep disruption actually precedes certain types of mental illness,” and that “in those young individuals who are at high risk of developing bipolar disorder, they already have a sleep abnormality prior to any clinical diagnosis of bipolar.”
On top of everything else connected to sleep disruption is that, according to Foster, it also aggravates existing mental illness.
In summary, Foster wants us to take sleep seriously. Adequate sleep improves your concentration, attention, decision-making, creativity, social skills, and overall health. It also reduces your stress, improves your mood, and reduces your tendency to drink or consume drugs.