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While you weren't sleeping...

Updated: Apr 11, 2018

We examine why not sleeping enough can make you HANGRY and FAT.

Ever wondered why you're killing it in the gym and not seeing the results?

The answer could be in your sleep patterns….

Even if your fitness routine is awesome, if you're not sleeping enough, you won't reap all the benefits. WHY?? –

While you're not sleeping, the body cooks up the perfect recipe for weight gain. Sleep is like nutrition for the brain. Most people need between 7 and 9 hours each night. Get less than that, and your body will react in ways that lead even the most determined dieter straight to the pizza shop and reaching for ice-cream.

We all get it - a little bit of insomnia - staring at the clock at 3am, 4am, 5am, restless, annoyed and then finally nodding off into a really, really deep sleep right before the alarm goes off. Starting the day out of whack, groggy and disorientated. Great.

But, what happens through lack of sleep that could make you fat?

If you’re interested in a more detailed explanation, I have included it further on in the blog (under “Science Stuff”).

For those of you who want to know in shorter, concise, laymen’s terms why lack of sleep may you turn into a ravenous, stressed, moody, irritable, reaching for every carb in sight, B#!ch (male or female) this bit is for you;

Basically, lack of sleep messes with your hormones, particularly ghrelin and leptin, which regulate our appetites;

Ghrelin tells you when to eat, and when you are sleep-deprived, you have more ghrelin, so your body thinks it needs to eat more.

Leptin is the hormone that tells you to stop eating, and when you are sleep deprived, you have less leptin, therefore you don’t know when to stop eating.

More ghrelin plus less leptin equals;

hunger, cravings for high sugar, high calorie foods, a slowed metabolism and therefore likelihood of weight gain.

On top of that (as if that wasn’t enough);

The more sleep-deprived you are, the higher your levels of the stress hormone cortisol, which also increases your appetite (and it’s not like you’re going to be suddenly ravenous for salads either).

When you’re stressed, your body tries to produce serotonin to calm you down. The easiest way to do that is by eating high-fat, high-carb foods that produce a neurochemical reaction.

Wait, there’s more;

Sleep deprivation also affects how your body responds to insulin. Studies have shown that a single night of sleep deprivation can cause as much insulin resistance as six months on a high-fat diet. What?

Insulin assists the entry of glucose from your food into your body’s cells. When your system gets loaded with glucose, it causes a shift in your metabolism and slows down fat breakdown.

And of course;

logically, if you’re completely shattered, it’s practically impossible to stay committed to a healthy lifestyle as you don’t have the energy for it.

Translation: Lack of sleep means you’re more apt to hang on to fat.

There’s nothing better than a solid night’s sleep for improving mood and energy levels. For most adults, this means 7 to 9 hours a night.

Get enough sleep. It seems simple, but it’s effective.

Sleep is like nutrition for the brain. Most people need between 7 and 9 hours each night. Get less than that, and your body will react in ways that lead even the most determined dieter straight to the pizza shop and reaching for ice-cream.



Lack of sleep has a dramatic effect on our hormones, and these hormones have a lot to do with weight loss and fat storage. The hormone leptin is intricately involved in the regulation of appetite, metabolism and calorie burning. Leptin is the chemical that tells your brain when you're full, when it should start burning up calories and, by extension, when it should create energy for your body to use. Ghrelin tells your brain when you need to eat, when it should stop burning calories and when it should store energy as fat.

During sleep, leptin levels increase, telling your brain you have plenty of energy for the time being and there's no need to trigger the feeling of hunger or the burning of calories. When you don't get enough sleep, you end up with too little leptin in your body, which, through a series of steps, makes your brain think you don't have enough energy for your needs. So, your brain tells you you're hungry, even though you don't actually need food at that time, and it takes steps to store the calories you eat as fat; so, you'll have enough energy the next time you need it. The decrease in leptin brought on by sleep deprivation can result in a constant feeling of hunger, cravings for high sugar and high calorie foods, and a general slow-down of your metabolism. During sleep, levels of ghrelin decrease, because sleep requires far less energy than being awake does. People who don't sleep enough end up with too much ghrelin in their system, so the body thinks it's hungry and it needs more calories, and it stops burning those calories because it thinks there's a shortage.

Translation: You’re more apt to hang on to fat.

To add to this, within just four days of sleep deprivation, your body’s ability to properly use insulin (the master storage hormone) becomes completely disrupted. When your insulin is functioning well, fat cells remove fatty acids and lipids from your blood stream and prevent storage. When you become more insulin resistant, fats (lipids) circulate in your blood and pump out more insulin. Eventually this excess insulin ends up storing fat in all the wrong places, such as tissues like your liver. And this is exactly how you become fat and suffer from diseases like diabetes.

When you don’t sleep enough, your cortisol levels rise. This is the stress hormone that is frequently associated with fat gain. Cortisol also activates reward centres in your brain that make you want food. At the same time, the loss of sleep causes your body to produce more ghrelin. A combination of high ghrelin and cortisol shut down the areas of your brain that leave you feeling satisfied after a meal, meaning you feel hungry all the time—even if you just ate a big meal.


Unfortunately, the disastrous impact spreads beyond diet and into your workouts. No matter what your fitness goals are, having some muscle on your body is important. Muscle helps you burn fat and stay young. Sleep debt decreases protein synthesis (your body’s ability to make muscle), causes muscle loss, and can lead to a higher incidence of injuries.

Lack of sleep makes it harder for your body to recover from exercise by also slowing down the production of growth hormone.

If you're trying to lose weight, and manage your body weight, but you're not getting sufficient sleep, 70% of all the weight that you lose will come from muscle and not fat.”


Sleep is like nutrition for the brain. Most people need between 7 and 9 hours each night. Get less than that, and your body will react in ways that lead even the most determined dieter straight to the pizza shop and reaching for ice-cream.

What can you do to help…?

  • Avoid eating heavy meals, caffeine and alcohol close to bed time.

  • Shut down your computer, mobile phone, and TV at least an hour before you hit the sack.

  • Save your bedroom for sleep and sex. Think relaxation and release, rather than work or entertainment.

  • Create a bedtime ritual. Take a warm bath, listen to soft music, meditate, or read. Relax.

  • Try to go to sleep and get up at the same time every day. This helps set your body’s internal clock and optimize the quality of your sleep. Choose a bed time when you normally feel tired, so that you don’t toss and turn. If you’re getting enough sleep, you should wake up naturally without an alarm. If you need an alarm clock, you may need an earlier bedtime.

  • Turn out the lights. Melatonin is a naturally occurring hormone controlled by light exposure that helps regulate your sleep-wake cycle. Your brain secretes more melatonin when it’s dark - making you sleepy -and less when it’s light - making you more alert.

by Nicky Jenkins

Can sleep on a clothes line

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