Sleep is essential for survival – especially quality sleep at the right time. It is a complex process that is important to brain functions and affects almost every type of tissue and process in the body – from metabolism to the immune function.

There are basically two types of sleep: rapid eye movement (REM) sleep and non-REM sleep, which constitutes of three different stages. Stage 3 of non-REM sleep constitutes the deep sleep that leaves you feeling well-rested the next day.

Sleep deprivation leads to the quickest reduction of health and increases risk for cancer, mental health, metabolic syndrome, obesity, Alzheimer’s and cardiovascular disease. It also adversely affects learning, concentration and memory.

Our society – the younger generations especially – is fairly “dark-deprived” due to high screen time. We need darkness to release melatonin, a hormone that induces sleepiness at night. The damage is twofold: on a biological level, and a mental one.

When you’re sleep deprived, you tend to eat more, and to derive less satisfaction from food. When you’re sleep deprived and dieting, changes in your body include inferior fuel partitioning, hyperinsulinemia and a tendency to crave more junk food.

With exercise and sleep, it’s very much a two-way street. Exercise early in the day is a great tool to promote sleep, and sufficient sleep improves exercise. That said, it is advisable not to exercise within two hours of your bedtime.

Every extra hour of sleep that a woman gets would mean a 13 to 15% increase in her desire to be intimate with her partner. With a ‘sleep divorce’, you might both actually enjoy better sleep as well as a more fulfilling physical relationship.

Lack of sleep causes a spike in cortisol, and also increases blood pressure or hypertension. All in all, it looks like sleep deprivation seems to accelerate or worsen cardiovascular health issues.

Try to listen to the natural rhythm of your body and try to fall asleep when you feel tired. Regular exercise, manipulations of body temperature and the use of exogenous agents like melatonin and magnesium can also help you fall asleep faster.

A lot of people think that they can compensate for the sleep deprivation they face during the week and sleep off their sleep debt over the weekend. Unfortunately, there is no “safety net” mechanism for those who are sleep deprived, so it is imperative to get sufficient sleep regularly, if not every night.

The state of your mental health affects your sleep, but poor sleep also affects mental health. A single night of sleep loss can induce anxiety in a person, and sleep disturbance is also a diagnostic symptom for some anxiety disorders.

Sleep trackers like the Oura ring and Fitbit can help you recognise your sleep pattern baseline and notice deviations from it. Sound blocking with devices such as white noise machines has demonstrated no harmful effects, and has been useful to many.