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Stress and Sleep

There are many misconceptions surrounding sleep and the best way in which to get it. Firstly, understanding the way in which the circadian rhythm of the body works is important to get the best out of your body.

The circadian rhythm is regulated by the absence and presence of light. There are two main types of light that affect the circadian rhythm, blue and red light.

Light obviously enters the body through the eye, which is a very complex organ. The eye is actually an extension of the brain, making it very sensitive to different kinds of light.

Blue light is emitted most abundantly at the beginning of the day. When we are exposed to this blue light, it causes a natural release of cortisol in the body. This cortisol is like a kickstarter for the circadian rhythm to supply the energy to start the day. As the day progresses blue light drops and the cortisol levels follow suit. As the blue light decreases, red light increases and so to do melatonin levels.

Cortisol gets the body ready and allows for more energy to be released. Melatonin works in opposition to cortisol, whereby it slows the heart rate, preparing the body for sleep. As you can imagine, if these hormones aren't released at the right time it can play havoc with our sleep. An effective way of making sure you get this natural kick of blue light, is getting up at sunrise.

A popular misconception is that blue light is negative and has a bad effect on us. Natural or artificial blue light is needed at the beginning of the day. This means that if you are going to have time in front of a computer screen, ensure it is in the daylight hours. The issue only arises when unnatural blue light exposure is a big part of the second part of the day i.e scrolling on your phone in bed or working into the night on your computer.

There are other factors than light that affect cortisol levels and ultimately, the sleep cycle. Exercise, stimulants, poor diet choices and sedatives can all negatively affect us.

Exercise can both positively and negatively affect us. The optimal time to exercise is earlier in the day. It gives a burst of endorphins, giving that feel good factor which can help with mood for the rest of the day. The release of adrenaline following exercise can impede

our sleep. It acts as a stimulant and can add to stress if you exercise too late in the evening.

Other stimulants such as caffeine and sugar can have a negative effect on us. The consumption of coffee or tea early in the day won't have as much of a negative effect as when consumed later in the day.

Diet choices can aid in the process of sleeping if we are aware of their effects. For example, natural unprocessed sources of fat, such as avocado or nuts, slows down the heart rate, due to the thickening effect of fat in the blood. This can help relax the body and encourage sleep. Conversely, sugar, especially processed sugar, can increase heart rate due to blood sugars increasing and ultimately, act as a stimulant.

Finally, sedatives such as sleep medications and alcohol can have long lasting effects on our natural sleep patterns. Our bodies can become reliant on the sedatives and not it's own natural mechanisms such as increased production of melatonin.

Take home messages

  1. Waking up at sunrise helps start the sleep cycle. Blue light is needed for this.

  2. Natural and artificial blue light exposure is best at the start of the day.

  3. Blue light exposure at night negatively affects sleep by increasing cortisol.

  4. Exercise is best earlier in the day as endorphins and adrenaline aid the body in the earlier hours of the day.

  5. Stimulants, such as caffeine, increase cortisol and can interfere with sleep patterns, particularly when consumed at night.

  6. Sedatives can negatively affect the natural processes that allow the body to sleep. With prolonged use, the body can become reliant upon them to achieve a sleeping state.

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