You’re time-pressed to complete a presentation that will impress, so you stay up way past bed time to get it done. Or perhaps, you need to run the numbers for that all-important report due yesterday. On the weekends, you’re out till late with your friends, trying to squeeze every minute free time to socialise and connect with people you’d otherwise not see.

Besides the obvious dark circles and pale skin, a lack of sleep will make you fat. The science behind this has been silently piling up for years, but we’re sounding the horn right now to make sure you don’t miss the memo.

Ghrelin is your gremlin

Leptin is the hormone produced by your body to regulate appetite and metabolism, while Ghrelin does the opposite. It motivates you to eat, tells the body when to stop burning calories and store fat. A study at the University of Lübeck, published in the American Journal of Clinical Nutrition, found that people who were sleep-deprived burnt five per cent less energy in general, and 20 per cent less energy post-meal.

unruly hair_need sleep

The reason for this lowered energy expenditure is that when you lack sleep, Leptin levels fall quickly, and Ghrelin takes over to give you a double whammy of weight gain: Your metabolism slows, yet you feel the need to eat more.

Cortisol joins the chaos

Ghrelin’s appetite increasing effect isn’t the only thing that causes weight gain. When you don’t sleep enough, your body’s natural reaction is to start creating the stress hormone Cortisol as well.


Cortisol helps to keep you going through the day, and lowers your reaction times somewhat, but higher levels of the stress hormone can make you irritable and grumpy. However, turning you into a grouch isn’t the only thing it does. Cortisol makes you crave fatty, oily foods as well.

We have evolutionary biology to blame for this, because our bodies evolved as a reaction to the highly stressful act of being constantly on the move and surviving skirmishes with predators. This cause the body to demand more high energy sustenance, hence the present day desire for oily and fatty food.

Helping our hormones

Sleeping well

We will not tell you to sleep more. That’s already hard to achieve with all our world-beating endeavours we have going on. However, here are some ways to immediately improve the quality of your sleep.

  • Don’t take any caffeinated drinks or alcohol in the evening. Caffeine keeps you awake, while alcohol messes up your sleep patterns.
  • Increase your exercise levels so you get restful, deep sleep. However, avoid exercise within three hours before bedtime.
  • Place all mobile devices on “Do not Disturb mode” before you sleep. Make sure they do not emit any noise at all.
  • Make sure your room is as dark as possible. Try to buy thicker curtains that block external light sources, and skip using night lights.
  • Stop using mobile devices or computers at least an hour before you sleep. Screens emit blue light which wreck your sleep patterns.
  • If you absolutely cannot set your mobile screen aside before you sleep, use “Night Shift” mode on your mobile devices. These lower the amount of blue light that reaches your eyes, allowing you to shift into sleep quickly.

Great sleep helps weight loss. More importantly, you’ll look and feel better and lead a more energised life. Sleep tight, and make every minute a restful one!