Lack of sleep is a health time bomb — here’s why you need to address your restless nights.

We live in a society that thinks it’s okay to skip a few hours sleep to get more done, whether that’s rising earlier to get to the gym or working late nights on yet another project. There is not one benefit to poor sleep, and yet we continue to rob ourselves of this absolute necessity.

How one bad night’s sleep affects your body:

DISRUPTED MELATONIN LEVELS

This is one hormone you do not want to interfere with. Melatonin is the hormone that encourages your body to feel sleepy, and the blue light in your smartphone tricks your body into thinking that it is daytime, and so it stops producing melatonin. You will find it harder both to fall asleep and to stay asleep, which is more than just a problem in itself. When melatonin levels are off, the hormones that control your appetite are also affected, meaning you are more likely to overeat. Research has proven that when melatonin levels are suppressed and the body clock is affected by light exposure, there is a higher risk of depression.

INSATIABLE APPETITE

Those hunger hormones? They’re pretty important. If you get less than six hours of sleep, your levels of the hormone ghrelin will go up, which is the hormone that signals hunger. At the same time, the hormone leptin, that gives you a sense of fullness, will drop. So when you’re sleep-deprived, you will feel hungry but never full, causing you to overeat.

NEUROTOXINS IN THE BRAIN

The brain is the organ that is most affected by poor sleep. While you are asleep, the space between your brain cells expands 60% more than when you’re awake, and that is when your brain eliminates built-up toxins. Neurotoxins are poisonous substances that affect the nervous system. The brain flushes out neurotoxins during sleep. Lack of sleep therefore leads to a build-up of neurotoxins, which can potentially destroy brain cells. One protein in particular, beta-amyloid, will not only further worsen sleep, but it is also linked to Alzheimer’s disease.

DISRUPTED BODY CLOCK

The body clock, or the circadian rhythm, is a lot more important than you may think. If the body clock is disrupted, over time it can lead to an increased risk of diabetes, cancer or cardiovascular disease. The circadian rhythm is responsible for a lot of jobs in the body — cell regeneration, brainwave activity, hormone production, and the regulation of glucose and insulin, to name a few — which is why it’s pretty crazy that we’re all willing to mess with our own bedtimes.

IMPAIRED BRAIN FUNCTION

A lack of sleep will affect your memory and your performance. It can also cause you to feel more anxious and unsurprisingly, it can have a negative impact on your mood. It’s unsurprising but completely true, you’re simply not going to be at your best after a restless night, no matter how many coffees you slug.

INCREASED HEALTH RISKS

Just one night without proper rest can quadruple your risk of catching a cold. And at the extreme end of the spectrum, a Harvard Medical School study found that people who slept fewer than five hours a night for five consecutive years have a 300 per cent greater risk of hardened arteries.