Not sleeping as well as you'd like? Your bedtime routine could be having more health consequences than you think.

Every night, without fail, people across the world climb into their beds and shut down for hours. This phenomenon we call “sleep” is something we are all very familiar with, but how exactly does it work? Up until the 1950s, it was widely believed that sleep was just a passive period of unconscious rest, but now we know that it’s a complex process that is essential to the rejuvenation of the body and mind.

When you’re asleep, your eyes are closed, most of your muscles are relaxed, and your consciousness is practically suspended. But while your body is still, your brain is quite active. Your body’s internal systems control when you sleep and when you’re awake. If these systems get out of alignment, due to work, illness, screen time or other reasons, it can have a big impact on your sleeping and bring about health problems as a result. In this piece, we will address what sleep is, why we need it, and the dangers of not having enough while providing some tips to help you improve it.

What Is It?

Sleep consists of REM sleep (rapid eye movement) and three NREM stages (non-rapid eye movement). During NREM the breathing and heart rate are slow and regular, the blood pressure is low, and the sleep is relatively still. As NREM sleep progresses, the brain becomes less responsive to external stimuli, and it becomes increasingly difficult to awaken an individual. This stage is linked to deep sleeping. During REM sleep your breathing becomes faster and irregular, and your heart rate and blood pressure increase to near waking levels. Your arm and leg muscles also become temporarily paralysed, which prevents you from acting out your dreams and this is when most of your dreaming occurs.

Over the course of the night your body moves four to six times through these different stages of NREM and REM sleep, spending an average of 90 minutes in each stage.

Each stage of sleeping serves a unique restorative function, including muscle recovery, hormone regulation, and memory, making it essential to allow enough time to cycle through all the sleep stages. A good night’s rest allows for growth and healing, as well as consolidation of memory and learning. Sleep is also thought to help keep your immune system strong and your heart and blood vessels healthy. Without a full night of rest, your body and mind are deprived of the essential elements needed to help you be your best.

How Much Sleep Do We Need?

Most of us need around 8 hours of good-quality slumber a night to function properly – give or take. Whereas teenagers need between 8 and 10 and younger children between 9 and 11 hours or longer depending on the age. Since appropriate sleep time allows for growth and learning it is particularly important for kids to get more rest for their development and mental alertness.

Generally, if you wake up tired and spend the day longing for a chance to nap, it’s likely that you’re not getting enough rest. A variety of factors can cause poor sleep, including health conditions such as sleep apnoea. But in most cases, it’s normally due to bad sleeping habits or stress.

Dangers of Not Getting Enough Sleep

Believe it or not, 1 in 3 of us suffers from poor sleep, with stress, computers, smartphones and taking work home often blamed. However, the cost of all those sleepless nights is more than just bad moods and a lack of focus.

Sleeping also helps control your appetite and your weight due to hormones released from fat cells known as Leptin and Ghrelin. Leptin suppresses hunger and signals to your brain when you’re full. Whereas Ghrelin is named the “hunger hormone”, is responsible for telling your brain you’re hungry and to seek out food. When you don’t get adequate rest, the body produces more Ghrelin and less Leptin, leaving you hungry and increasing your appetite.

While an occasional night without sleep makes you feel tired and irritable the next day, it won’t kill you. Although after several sleepless nights, the mental effects can become more serious. Your brain will start to fog, causing difficulty in concentration and decision-making. You’ll start to feel down, lethargic or fall asleep during the day. This can result in an increase to your risk of injury and accidents, while also being detrimental to both your physical and mental health.

Sleep is essential for a healthy heart too. People who don’t sleep enough are at higher risk for cardiovascular disease and coronary heart disease—regardless of age, weight, smoking and exercise habits. Getting enough good quality rest is important if you want to lower your risk of these conditions. It’s not completely clear why less sleep is detrimental to heart health, but researchers understand that sleeping too little causes disruptions in underlying health conditions and biological processes like glucose metabolism, blood pressure, and inflammation. The same may be true for oversleeping as well.