Once you decide to really get in shape and control your weight, usually you start by building a plan, which involves some changes in your everyday life. You get up early in the morning to have a run or you perform a carefully chosen fitness routine, your breakfast contains new substances in smaller portions and so on.
BUT the rest of your obligations are not about to disappear along with the second slice of bread and all the sugar from your coffee.
Professional fitness models that have The Body are completely devoted to their figures, because this is their hobby and a job. It is hard to compete with them (or be like them), while fighting with our typical daily routine which includes a job, taking care of kids, cooking, cleaning and somehow finding time to relax and pay attention to our social life. At some point you try to fit it all in only 24 hours and the easiest thing to spare time from is… your sleep.
The thing is sleep deprivation usually works against you when it comes to weight loss. It can change your metabolism even when inflicted for very short periods of time such as two days, for example.
My hormones say I’m hungry: Ghrelin
Ghrelin is called “the hunger hormone”, because it is a neuropeptide, regulating the appetite and the rate of energy use. When your stomach is empty, ghrelin is secreted. When the stomach is stretched, secretion stops. This hormone acts on hypothalamic brain cells triggering the increase of gastric acid secretion and gastrointestinal motility so your body is ready to digest and of course it promotes the feeling of being hungry. Its secretion is also connected to your emotional state which makes it part of the so called “emotional eating” that many people suffer from.
My hormones say I’m hungry: Leptin
Leptin is the old enemy of ghrelin. It’s called the “satiety hormone” and its function is to regulate energy balance by inhibiting hunger. Some people are leptin resistant – they have a decreased sensitivity to leptin, resulting in an inability to detect satiety despite high energy stores.
The normal sleep duration for an adult is about 7-9 hours per night. Now what happens when you don’t sleep enough?
First of all, when you don’t get enough sleep your body goes into survival mode. This is a huge stress for your organism. Surprisingly, a lot of people think that being stressed helps you lose weight, but in reality this could only happen after a very dramatic event such as losing your job, losing a beloved member of your family and so on. And in this cases nobody cares about their waist line. When the levels of stress come up from a daily situation such as sleep deprivation, things are a little different.
The more sleep-deprived you are, the higher your levels of the stress hormone cortisol, which increases your appetite. Even worse, you’re hungry for high calorie food, because when you’re stressed your organism tries to calm you down by producing serotonin (the hormone of happiness). The easiest way to do that is by eating high-fat, high-carb foods that produce a neurochemical reaction. And just when you thought it can’t get worse: your body’s ability to process the sweet stuff is reduced. Sugar remains in your blood instead of being converted to pure energy in mitochondria. And despite eating high-calorie food you still feel tired and this makes you less likely to do any type of exercise. I know, you are determined and you will after all push yourself to workout, BUT your exercise will be less effective, because your muscles won’t have the energy for it. When you’re done, you’ll be even hungrier for sweets, because an average workout utilizes at least partialy the amounts of glycogen you have stored and of course, this has to be restored.
After only two days of sleep deprivation – 4.5 hour of sleep per night or none, ghrelin levels in your blood will start to rise. And now you know that this hormone makes you feel hungry.
At this point leptin levels are not yet influenced significantly.
However, longer periods of time with reduced sleep lead to lowering of leptin levels and now you know that not enough leptin means being hungry.
These consequences are not necessarily activated only after drastic sleep deprivation as the example of 4.5 hours of sleep. Such observations are noted in cases of longer life periods of sleeping for 6 (or for some people even 7) hours per night. A study, made in Quebec shows results which state that both sleep deprivation and oversleeping can ruin your dietary regime.
If we want to summarize, we can say that cutting from your sleep time while trying to lose weight is a very bad idea, because:
- You get stressed thus your cortisol levels rise => you’re hungry;
- You get stressed thus your body wants to fill you up with junk food in order to make you happier;
- You digest all this junk food worse;
- You don’t have the energy to sufficiently burn all these calories with a proper workout;
- The levels of ghrelin in your blood serum rise => you’re hungry;
- The levels of leptin in your body drop => you eat, but you still feel hungry.
What can you do now?
Sometimes you might not even know that you’re not having enough sleep. You just go with the flow, and you don’t count the hours of sleep, but these little buddies – your hormones know it all. Surprisingly, if you consistently prolongue your sleeping time with an hour or two you will most probably drop a little weight only due to this minor change! You need to know that now working out you might need even a bit more sleep than the average person who doesn’t do sports. This extra nap will help you restore your energy, let the muscles grow and the fats to burn. It will prevent some overtraining injuries and most of all – it’ll make you feel at least a bit happier.
So now you know what to do… relax and take a nap.
If you are interested in this topic, if you have any questions or if you would simply like to share your experience on this matter, you can join the discussion in the forum of Cake in The Six Pack. 🙂
“A single night of sleep deprivation increases ghrelin levels and feelings of hunger in normal-weight healthy men”. S. M. Schmid, M. Hallschmid, K. Jauchara, J. Born and B. Schultes. J. Sleep Res. (2008) 17, 331–334
“The Association Between Sleep Duration and Weight Gain in Adults: A 6-Year Prospective Study from the Quebec Family Study”. J. Chaput, J. Després, C. Bouchard, A. Tremblay. SLEEP, Vol. 31, No. 4, 2008
“Short Sleep Duration is Associated with Reduced Leptin, Elevated Ghrelin, and Increased Body Mass Index”. Sh. Taheri, L. Lin, D. Austin, T. Young, E. Mignot. Plos Medicine, December 7, 2004