How to get a good night’s sleep
Understanding your biological clock is the key to a healthy night’s sleep
Your body is driven by an internal circadian master clock known as the suprachiasmatic nucleus, which is set on a time scale of roughly 24 hours. This biological clock is set by sunlight; blue light hits special receptors in your eyes, which feed back to the master clock and on to the pineal gland. This suppresses the production of the sleep hormone melatonin and tells your brain that it is time to wake up.
Disruptions in light exposure can play havoc with your sleep, so it is important to ensure that your bedroom is as dark as possible. Many electronic devices produce enough light to reset your biological clock, and using backlit screens late at night can confuse your brain, preventing the production of melatonin and delaying your sleep.
Ensuring you see sunlight in the morning can help to keep your circadian clock in line, and sticking to a regular sleep schedule, even at the weekends, helps to keep this rhythm regular.
Another important factor in a good night’s sleep is winding down before bed. Stimulants like caffeine and nicotine keep your brain alert and can seriously disrupt your sleep, and even depressants like alcohol can have a negative effect; even though it calms the brain, it interferes with normal sleep cycles, preventing proper deep and REM sleep.
The dangers of sleep deprivation
Lack of sleep doesn’t just make you tired; it can have dangerous unseen effects
1) Impaired judgment
Sleep deprivation impacts your visual working memory, making it difficult to tell the difference between relevant and irrelevant stimuli in your environment, and affects your emotional intelligence, behaviour and ability to manage stress.
2) Weight gain
Sleep deprivation affects the levels of hormones involved in regulating appetite. Levels of leptin (the hormone that tells you how much stored fat you have) drop, and levels of the hunger hormone ghrelin rise.
3) Raised blood pressure
Poor sleep can raise blood pressure, and in the long term is associated with an increased risk of diseases such as coronary heart disease and stroke. This danger is increased in people with sleep apnoea.
4) Mood disorders
Mental health problems are linked to sleep disorders, and sleep deprivation can play havoc with neurotransmitters in the brain, mimicking the symptoms of depression, anxiety and mania.
Severe sleep deprivation can lead to hallucinations; seeing things that aren’t really there. In rare cases can lead to temporary psychosis or symptoms that resemble paranoid schizophrenia.
This article was originally published in How It Works issue 70, written by Laura Mears
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