• For a long time in the history of humans, we did not know the answer to the question, "Why is sleep so necessary?". We knew that it was not the best thing in the world to be sleep deprived but we didn't know its true significance
• One of the simplest effects of routinely sleeping less than six or seven hours a night demolishes your immune system, more than doubling your risk of cancer.
• If you ask me, this is enough of a reason to sleep more. Basically, Shakespeare was right in Macbeth.
• Moreover, Insufficient sleep is a key lifestyle factor determining whether or not you will develop Alzheimer’s disease. Inadequate sleep—even moderate reductions for just one week—disrupts blood sugar levels so profoundly that you would be classified as pre-diabetic. Short sleeping increases the likelihood of your coronary arteries becoming blocked and brittle. Sleep disruption further contributes to all major psychiatric conditions, including depression, anxiety, and suicidality.
• This is not something that I am making up. This is what research tells us. Hundreds of years of research.
• Perhaps you have also noticed a desire to eat more when you’re tired? This is no coincidence. Too little sleep swells concentrations of a hormone that makes you feel hungry while suppressing a companion hormone that otherwise signals food satisfaction. So....if you want to loose weight, sleep!
• This has been the single most life-changing habit that I have developed. I don't say stuff like this much but if you want to develop a new habit, it should be sleeping.
• The amount of sleep required changes from age-group to age-group
• Basically, teenagers need 8 to 9 hours of sleep whereas, adults need $7 \frac{1}{2}$ to $8 \frac{1}{2}$ hours of sleep.
• I know this sounds absurd, my thoughts when I first heard about this was "How in the world am I supposed to get that amount of sleep!".
• A note about waking up early and going to bed early. I have previously mentioned that I wake up at 5:30 and go to sleep at 9. I know this is not the most desirable thing to most of you.
• In the book Why we sleep?, the author talks about the fact that not everyone can biologically wake up early and go to bed early. There are two kinds of people, "Morning Larks" and "Night Owls". It is not necessary to wake up early. You can go to sleep early and wake up early or go to bed late and wake up late.
• A note at this point. So whenever I tell people about the "Morning Larks" and the "Night Owls", they just assume that they are Night Owls. I won't say that there are significant benefits to being the "Morning Lark". It doesn't really matter if you are Night Owl or not. But....there is a little bit of a caveat. For one teenagers are, by default, "Night Owls". Biology is at fault here. It is physically harder for teenagers to fall asleep early and wake up early. There melatonin levels aren't simply high enough at say, 9 PM. Most adults can easily fall asleep early and wake up early. Old people are even earlier risers. They can wake up at 4 AM easily and fall asleep at 8 Easily.
• The school system sadly doesn't acknowledge that most of their students have been woken up too early
• Adolescents face two other harmful challenges in their struggle to obtain sufficient sleep as their brains continue to develop. The first is a change in their circadian rhythm. The second is early school start times. The complications of early school start times are inextricably linked with the first issue—a shift in circadian rhythm. As young children, we often wished to stay up late so we could watch television, or engage with parents and older siblings in whatever it was that they were doing at night. But when given that chance, sleep would usually get the better of us. The reason is not simply that children need more sleep than their older siblings or parents, but also that the circadian rhythm of a young child runs on an earlier schedule. Children therefore become sleepy earlier and wake up earlier than their adult parents. Adolescent teenagers, however, have a different circadian rhythm from their young siblings. During puberty, the timing of the suprachiasmatic nucleus is shifted progressively forward: a change that is common across all adolescents, irrespective of culture or geography. So far forward, in fact, it passes even the timing of their adult parents. As a nine-year-old, the circadian rhythm would have the child asleep by around nine PM, driven in part by the rising tide of melatonin at this time in children. By the time that same individual has reached sixteen years of age, their circadian rhythm has undergone a dramatic shift forward in its cycling phase. The rising tide of melatonin, and the instruction of darkness and sleep, is many hours away. As a consequence, the sixteen-year-old will usually have no interest in sleeping at nine PM. Instead, peak wakefulness is usually still in play at that hour. By the time the parents are getting tired, as their circadian rhythms take a downturn and melatonin release instructs sleep—perhaps around ten or eleven PM, their teenager can still be wide awake. A few more hours must pass before the circadian rhythm of a teenage brain begins to shut down alertness and allow for easy, sound sleep to begin. This, of course, leads to much angst and frustration for all parties involved on the back end of sleep. Parents want their teenager to be awake at a “reasonable” hour of the morning. Teenagers, on the other hand, having only been capable of initiating sleep some hours after their parents, can still be in their trough of the circadian downswing.
• No matter how much that teenager truly wishes to obey your instruction, and no matter what amount of willed effort is applied by either of the two parties, the circadian rhythm of a teenager will not be miraculously coaxed into a change. Furthermore, asking that same teenager to wake up at seven the next morning and function with intellect, grace, and good mood is the equivalent of asking their parent, to do the same at four or five AM. Sadly, neither society nor our parental attitudes are well designed to appreciate or accept that teenagers need more sleep than adults, and that they are biologically wired to obtain that sleep at a different time from their parents. Parents would be wise to accept this fact, and to embrace it, encourage it, and praise it, lest they wish their own children to suffer developmental brain abnormalities or force a raised risk of mental illness upon them. It will not always be this way for the teenager. As they age into young and middle adulthood, their circadian schedule will gradually slide back in time.

If you want to learn more about sleep check out Why we sleep by Mathew Walker