Sleep loss generates stress
We always like to point out that the recipe for weight loss is quite simple. Eat less and do some exercise. Finally, it is a matter of cutting your energy balance. Less energy in, more energy out. That's it. The problem is not the recipe. The problem is the people. It's us. We hate weight loss because it hurts on a physical and psychological level.
Weight loss causes stress for your body and we only can handle a certain amount of stress. If our stress gets to high our body starts a revolution and the strangest behavior patterns can show up. Fatigue, binge eating, depression, etc.
Now how is sleep connected to all this?
Our body needs sleep to recover. We should sleep about 8 hours per day to fully recover our brain and our muscle apparatus. If we sleep less we get tired and less productive. Sleep deprivation is simply another source of stress for us.
A study published in the International Journal of Obesity and carried out by the Kaiser Permanente Center for Health Research found out that sleep deprivation can reduce the success of a diet significantly. People who had less than 6 hours sleep daily were about half as likely to be successful at weight loss. This is a significant difference for people that want to lose weight!
Why is that?
Stress gives us a bad feeling. We are tired and we feel already burdened with smaller tasks. We are less productive and we fail more often. How does our brain react to this feelings? Our brain wants us to feel good so it tries to cut down our work load and activates our internal reward systems. It will do everything to make us feel better.
Hard work? Not now! We need to chill now. We do that later. Sweets? Yes of course. They increase our blood sugar, give us fast energy and make us feel good. Let's have some sweets now. Meal size? Let's eat big today! We need the energy because we are so tired. We can continue our diet tomorrow...
Our brain is a bastard when it comes to playing tricks on us. It means hard work for us and conscious decisions to keep our brain under control. Our limbic system, the oldest part of our brain can run our body on a base level. It is center of our basic feelings: fight, flight, fear, freezing up, feeding, gluttony...
When our cerebrum is on holidays because it is too tired to work properly our lizard brain takes over control and we are victims to our most primitive behavior patterns. Eating & resting in this case ...
Sleep loss & fitness
Besides the negative effect on our eating behavior we destroy our fitness results. There are many studies on the effect of sleep on our fitness performance and muscle recovery. It is known that fitness performance decreases and it is harder for our body to recover from sports when sleeping not enough.
One point that should not be underestimated is the willingness to go out and do sports when you are tired. It is the same process with a diet. It needs effort to do sports and weight loss and when we are stressed out our lizard brain will tend to keep us lying on the couch and recover while eating some sweets and watching the Sunday game.
We need balance to stay focused and persistent and sleep is very important for our balance. If you sleep enough you will be more productive in your fitness units because you will be more focused. You will also be more persistent and will not skip your fitness units because you are too tired. Balance leads to focus and persistence, and to be balanced we need enough sleep!
The biochemistry of sleep loss
Last but not least sleep loss has an effect on our hormone balance. A study carried out by the University of Chicago found that after 4 days of sleep deprivation our insulin sensitivity can drop by 30%. That means our body needs to produce more insulin to remove lipids and fatty acids from our blood stream. With this excess of insulin our body ends up storing fat in wrong places. This effect can lead to weight gain, diabetes and other health problems over a long time frame. Our fat cells need sleep just like we need it. It turns out that without sleep our fat cells are kind of "metabolically groggy" and are not able to make a good job.
Another interesting finding of the study is the decrease in leptin production. The hormone leptin is a major biochemical player when it comes to the feeling of being full. Leptin makes us stop eating and prevents overeating. The production of leptin happens in the fat cells. The study found that sleep loss causes a decrease in leptin production.
So basically, what we observe on a macro level when being tired, which is being hungrier and craving for sweets can be explained on the micro level by a decreased leptin production. Cause & Effect!
The bottom line
Sleep has a positive effect on our diet results. You should try to sleep 8 hours per day and avoid sleep deprivation over a long time frame by all means. Having enough sleep will make you more productive and it will be easier to achieve your weight loss and fitness goals. Besides that, enough sleep helps your metabolism to work properly and it can help you to stay healthy and avoid several chronic diseases like diabetes.
Impact of sleep, screen time, depression, and stress on weight change in the intensive weight loss phase of the LIFE study; Elder CR, Gullion CM, Funk KL, DeBar LL, Lindberg NM, Stevens VJ.; Int J Obes (Lond) 2012 Jan
Does Central Fatigue Explain Reduced Cycling after Complete Sleep Deprivation?; Temesi, John; Arnal, Pierrick J.; Davranche, Karen; Bonnefoy, Régis; Levy, Patrick; Verges, Samuel; Millet, Guillaume Y.; Medicine & Science in Sports & Exercise; 2013 Dec
Impaired Insulin Signaling in Human Adipocytes After Experimental Sleep Restriction; Josiane L. Broussard, David A. Ehrmann, Eve Van Cauter, Esra Tasali, Matthew J. Brady; Ann Intern Med. 2012 Oct