While you are asleep, the human body cycles through two phases of sleep, namely Non-REM (rapid eye movement) sleep and REM sleep.
The first part of the cycle is non-REM sleep, and it is further divided into four different stages:
Stage 1 – This is short, and represents the time between being awake and falling asleep i.e. dozing off and transitioning into sleep.
Stage 2 – This is light sleep, where body temperature drops, and heart rate and breathing are regulated, and are slowed down.
Stage 3 & 4 – This is deep sleep, where the body slows down even further, and overall brain activity slows and shows a pattern of pulses of activity that are believed to prevent unwanted awakenings.
As the cycle transitions from non-REM sleep above to REM sleep, the eyes move rapidly behind closed eyelids, brain activity increases to levels similar to when you are awake, your heart rate and breathing increase, and your muscles become temporarily paralyzed.
Each sleep cycle averages 90 minutes and the body cycles through these stages about 4 to 6 times per night. As each cycle repeats itself, you spend less time in the deeper stages three and four of non-REM sleep and more time in REM sleep.
What factors affect sleep?
Age: Notable changes in sleep are associated with aging. Studies show that 43% of elderly individuals have difficulty in initiating and maintaining sleep. Older adults also tend to experience insomnia and earlier wake times.
Sleep apnoea: Individuals with sleep apnoea experience airway collapse in deeper sleep states, causing them to experience reduced time in stages 3 and 4 of non-REM sleep and REM sleep.
Depression: A decrease in REM latency (the time between sleep onset and the start of the first REM period) and an increase in REM sleep has been observed in individuals with depression.
Other medical conditions: Chronic pain from medical conditions such as gastro-oesophageal reflux disease and arthritis have shown to disrupt sleep. Those with stress and anxiety find it more difficult to fall asleep.
Medication: Prescription medication including beta blockers, alpha blockers, and antidepressants all have an effect on sleep quality and quantity. Most antihistamines have a sedative side effect and are often found in many over the counter medications.
Substance abuse: Caffeine, alcohol and nicotine can all affect the quality and quantity of sleep. Caffeine products have been shown to decrease an individual’s sleep patterns. Alcohol can help you fall asleep more quickly but quality of sleep under the influence of alcohol may be reduced. Nicotine in cigarettes has also been shown to disrupt sleep patterns.
Basic tips to improve sleep:
Monitor your caffeine intake: Caffeine found in commercially available products such as brewed coffees as well as energy drinks can cause sleep disturbances. Chronic consumption has further shown that it can cause long-term sleep deprivation. Monitor your caffeine intake and avoid it later in the day.
Find the right mattress and pillow: Choosing a mattress to meet your needs is a sound investment. Make sure that the mattress suits your body type and is of the appropriate degree of firmness. This coupled with the right pillow will ensure your spine gets the proper support.
Natural sleep aids and supplementation: These can assist with sleep but you should always seek advice from a medical professional before taking them.
Natural sleep aids are products that can potentially address mild to moderate insomnia and sleep issues. These products include a wide selection of over-the-counter sleep supplements, however, there is limited evidence for some of these supplements.
Some of these include:
5-hydroxytryptophan (5-HTP): 5-HTP is a precursor of the neurotransmitter serotonin, also known as the “feel good” neurotransmitter. Serotonin is required by the body to make melatonin, an important hormone for sleep regulation. Melatonin does not make you sleep but rather puts you in a state of quiet wakefulness that helps promote sleep.
Research suggests that melatonin is helpful for circadian rhythm disorders because it tells your body it’s time for sleep by timing your circadian rhythm. Generally, a safe starting dose of melatonin for adults is between 1 milligram and 5 milligrams an hour before bedtime. Melatonin should be avoided if you are pregnant or breastfeeding, or if you have an autoimmune disorder, epilepsy or depression.
L-Theanine: This is an amino acid that targets stress levels that may be keeping you awake. Studies suggest that the administration of 200mg of L-theanine before bed may support improved sleep quality. It is considered to be a safe natural sleep aid because unlike conventional sleep inducers, it promotes relaxation and good quality sleep without drowsiness or sedation.
Gamma-aminobutyric acid (GABA): This is a chemical in the brain that boosts relaxation and sleep. Many prescription sleeping pills work by boosting GABA in the brain, which has led to the suggestion that GABA supplements might help with stress and sleep. In 2020, a medical review concluded that there was limited evidence to GABA’s sleep benefit when supplementing orally – this was due to its inability to cross the blood-brain barrier and get into the brain.
Magnesium: Magnesium is a common mineral used in sleep supplements to help improve sleep quality by relaxing the body. Studies show that low levels of magnesium may make it harder to stay or fall asleep. Taking excessive amounts of magnesium can cause gastrointestinal side effects such as diarrhoea. It is considered safe to take in pregnancy but always consult with your doctor first.
Valerian: Valerian has been used as a sleep aid as far back as ancient Greece and Rome. It stems from a flowering plant native to Europe and Asia and produces a mild sedating effect. It is considered safe if you take it in the recommended doses but should be avoided in pregnancy.