Apollo 8, December 24, 1968. William Anders: Oh my God! Look at that picture over there! There’s the earth coming up. Wow, that’s pretty. Photograph courtesy of NASA.
The crew of Apollo 8 saw the earth rising. They knew, that although they had set out to explore the moon, they had discovered the earth. Earthrise, a photograph that changed the world, is celebrated as one of the most influential photographs ever. Anders was honoured by the International Astronomical Union, when they named one of the large craters in the photo ‘Ander’s Earthrise’. In Earthrise, we woke up to the beauty, loneliness and fragility of our planet.
Just like the earth, we sleep, we rise. Every day this happens. That’s how life works. Life is dictated by rotation of the earth on its own axis. The daily change in light gives life on earth its circadian rhythm. We adjust our lives, our bodies and our hormones on the basis of this natural rhythm. All life, animals, bugs and plants have circadian rhythm. Circadian rhythm means that different things happen, as the day turns to night. During the day, there is building, energy expenditure and activity. At night, there is resting, repair and regeneration. Your body changes as the phases of the 24-hour cycle change.
Circadian rhythm is set and managed by body clocks. You have a master clock in your brain and local clocks are scattered in virtually every organ. Your master clock keeps your local clocks in synchrony. Your master clock reacts to a change in light levels, with direct input from your eyes. Your master clock controls the production of hormones such as melatonin, which help you to go to sleep. Some of the local body clocks react, not to light but to other things such as temperature, but the master clock always has the upper hand 1.
Your circadian rhythm governs many biological functions. Animals, gut bugs and even plants have their own body clocks. Your body clock controls the sleep-wake cycle, hormone release, eating habits and digestion, body temperature and other important bodily functions. Our body clocks can and do become unsynchronised. You can imagine that this doesn’t do us any good – hormones go haywire, energy levels are affected, and sleep suffers. Then our health suffers.
We each have unique circadian rhythms. Some people are most alert in the morning others at night, so-called morning larks or night owls. Efforts to elucidate the reasons for these differences have only now yielded results. We are starting to understand the mystery. And the differences come from your genes. A genetically determined difference in the length of the pause button in our body clocks determines these differences.
An alteration of your circadian rhythm affects your body homeostasis. Hormones go out of sync. Hormonal disruption leads to disturbances of the sleep-wake cycle. Irregular circadian rhythms have been linked to many chronic health problems such as obesity, high blood pressure, diabetes, cancer and dementia. Loss of the normal circadian rhythm is also associated with increased deaths, due to heart disease and strokes. Disturbances of circadian rhythm influence our entire bodies, and a universal finding is over-action of the sympathetic nervous system, a stress reaction. It causes many chemical changes, including inflammation, which is something that you want to avoid for good health. If inflammation goes unchecked, you are at risk of developing many long-term diseases 5, 8, 9.
Circadian rhythm is altered in jet lag, long-term shift workers and in the Monday morning blues. Shift work is linked to increased heart disease and death, from all causes. People pay a heavy price to keep hospitals open, the hospitality industry working and the wheels of industry turning. People who have different sleep patterns at the weekends compared to during the working week may experience social jet lag. The pattern is outlined here: as you don’t have to get up for work at the weekend, you may get up an hour or two later that you do during the week. You may also push your bedtime back, so that you can go out with friends. Many people sleep on a different schedule, at the weekend, compared to during the week. Switching sleep schedules is similar to changing time zones and is called social jet lag, which can take a hefty toll on your health 2, 3.
If you want perfect health, you need both the right quality sleep and the right amount of sleep. Sleep deprivation results in early death, mood changes, poor immunity, hypertension, risk of heart disease, risk of diabetes and the list goes on. Lack of sleep is a huge risk factor for ill health. To be well, you must have enough high-quality sleep. There is no way round this and pretending otherwise is foolish 4, 7.
During sleep, your body processes go from active to resting. When you go to sleep, your heart rate and breathing slow and your muscles go limp. That’s why we can’t sleep in trees, we would fall out. During sleep, growth hormone, appears in high concentrations and repairs your muscles following the day’s toil. Athletes are very aware of the importance of a good sleep habit, which allows their body to repair and subsequently improve performance. Sleep is so important to health that when we change our sleep even by an hour, we can see the direct effects 11.
Sleep is essential for brain health, particularly for tasks such as memory and learning. Your brain is particularly active during certain phases of sleep. Sleep restores the brain and allows memory management. Data is transferred from your short-term memory storage area to your long-term area. During the day, the short-term storage fills up. At night, this data is transferred to long-term storage. Sleep clicks the save button on what you have learnt during the day. The crowded short-term storage area then has room for the activities on the following day. But only in REM sleep. If you don’t get enough REM sleep, your memories will not be saved. Good quality sleep is a prerequisite for a healthy you, both for your brain and your body.
We all know when we are not getting enough sleep, because our brains don’t work as well as they usually do, our memory is poor, our emotions may be labile, and we may accidentally fall asleep during the day. We recognise the problems caused in our brains from sleep deprivation. But we may not have thought about what was happening in our bodies at the same time. If we don’t sleep well, our bodies are under stress and ill health will follow.
Sleep needs to be a routine, which means going to sleep and getting up at the same time every day. 7 hours sleep is the magic number. Consistently sleeping between 6 and 8 hours per night is optimal for health and no studies show that this amount of sleep is harmful. There is widespread agreement that if you sleep less than 6 hours per night, you are at risk of developing health problems. There is some evidence that sleeping longer than 8 hours is associated with disease risk, but there is less widespread agreement about this point 6.
Top Five Tips on Sleep Routine: How to Sleep Better
Simple attention to sleep hygiene can work wonders, if you are having problems sleeping. Here are some tips to improve your sleep.
Go to bed and rise at the same time each day - have a routine. The reason that you need a routine for sleep is that it takes many different hormonal responses, in the body to allow you to sleep. These hormones are regulated by the master clock and the other body clocks. The clocks follow circadian rhythms and do certain things at certain times. You do not have conscious control over these clocks. They become accustomed to the rhythm of your body and then work together in synchrony to get you to sleep and to wake you up. Your body clocks should work together, at the same time each day. The clocks can change the time at which they go on and off, but, only slowly. The body clocks can change at most one hour per day. To have a good sleep pattern, you have to respect the circadian rhythm of your body clocks. If you go to sleep at the same time every night, the body clocks will work in harmony with you. They will start to prepare your body for sleep, hours before you go to sleep. Your body temperature starts to fall, your heart rate slows, your appetite reduces, and your metabolic rate slows. Co-ordinated, it is a perfect recipe for allowing us to become unconscious of the world and then wake up again. Un-coordinated, it’s a mess.
Finish your meals within four to six hours of bedtime Eating before bedtime is not conductive to a good night’s sleep. Once you eat, your body has to digest the food, absorb it, process it and then arrange for storage. That’s a lot to do, in addition to going to sleep. If you eat a few hours before you want to go to sleep, it takes your gut out of the equation.
Make your bedroom conducive to sleep - dark, cool and no screens Your bedroom needs to be a place where you concentrate on two things, sleep and love. You should not work in your bedroom, nor exercise, nor eat etc. It should be a place which is separate from your daily life and somewhere that your body and mind associate with sleep. Screens are not conducive to sleep, whether they are on or off, so try not to have any screens in your bedroom. Your master clock responds to light and dark, which signals sleep. Help your master clock to recognise the trigger of darkness, keep your bedroom dark. Your body temperature drops during sleep and a cool bedroom is more conducive to sleep, as your body has less work to do to cool you down.
Don’t exercise vigorously immediately before bed: try to finish 1-2 hours before bedtime. Exercise elevates your body temperature and causes release of hormones, which push you in a direction, opposite to one of sleep. If you allow time between exercise and sleep, your exercise hormones dissipate and your body temperature returns to normal, meaning that your sleep hormones can take over before bedtime .
Birds of a feather stick together. Morning larks live with larks; night owls, live with owls. You can’t change from a lark to an owl. This type of sleep pattern is genetically determined and there are different speeds of body clocks, due to a difference in the length of the pause buttons. Generally, in modern society, night owls tend to suffer sleep deprivation more than morning larks. Moring larks are the thugs of the sleep world. If your partner has a different sleep pattern to you, consideration and planning, will go a long way to allowing each other to sleep well.
Alcohol disturbs your sleep and thus ultimately harms you. Most people think that they sleep well after alcohol, but this is far from the truth. The sleep after alcohol is in fact sedation, not high-quality sleep. Alcohol induced sleep does not have the right mix of light and heavy sleep. The normal vital brain reparative processes which occur during sleep, in particular related to memory, are not completed and this causes lasting health problems. Interesting, but many sleep scientists don’t drink alcohol. If you can’t emulate the sleep scientists, try dodging bullets. We speak about dodging bullets in the Diet Whisperer, try avoiding alcohol a few nights a week and then you have high quality sleep, at least some of the time 12.
Once your sleep hygiene is good, you may want to look at other aspects of wellness. Sleeping well is one of the most important things that you can do to improve your health and well-being. Knowledge is power and knowing how important sleep is to health, is a powerful motivator to improve sleep quality.
We hope you learn something from this e-article, and that we help you to improve your health. As we say at Whisperer HQ: “Take back control. See instant results. Become the Diet Whisperer for you and your loved ones.”
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