Can lack of sleep make you fat? Apparently, yes!
Over the years there have been a number of small studies that have hinted at the possibility that lack of sleep can affect your weight. However, in general, the effect was thought to be small and so the observation didn't get as much attention as it should have.
Other studies have shown that stress can also affect your weight and influence your diet. You may not have heard much about cortisol, however, not knowing about it does not reduce its impact on you. Cortisol is one of your bodies stress hormones and is also a hormone that puts your body into an eat and conserve calories mode.
Cortisol is very, very similar to cortisone or prednisone. These drugs you may have heard of and there is a good chance that you may have even taken these types of drugs. They are prescribed as anti-inflammatory drugs and they are very, very effective. They are used for immune and autoimmune diseases, asthma and arthritis. They can also be used to manage short-term of significant inflammation.
Almost anyone who has taken these drugs will tell you that their appetite went through the roof and their weight shot up like a rocket. These things happened because that is what cortisol does naturally.
Since cortisol is released in response to stress, you can see how having a stressful job or family life can lead to hunger that is difficult to control and a steady gain in weight.
Before we put stress and sleep problems together, let me quickly run through the result of the study.
The study was published in the June 2013 issue of the Journal Sleep. The authors were from the Department of Psychology at the University of Pennsylvania. The goal of the study was to “examine sleep restriction's effects on weight gain, daily caloric intake, and meal timing.”
The researchers found that “Sleep-restricted subjects gained more weight than control subjects. Among sleep-restricted subjects, African Americans gained more weight than Caucasians and males gained more weight than females.”
Sleep-restricted subjects consumed extra calories during days with a delayed bedtime compared with control subjects who did not consume extra calories during corresponding days.”
The study determined that “in sleep-restricted subjects, increased daily caloric intake was due to more meals and the consumption of additional calories [after normal bedtime].” They also found that “the percentage of calories derived from fat was greater during late-night [eating] compared to daytime and evening [meals].” (In the summary above, the specific data and statistics were removed for readability, if you want to see the actual data, please follow the link.)
The final conclusion of this very large study was that “ …sleep restriction promoted weight gain. Chronically sleep-restricted adults with late bedtimes may be more susceptible to weight gain due to greater daily caloric intake and the consumption of calories during late-night hours.
So now we can put sleeplessness and stress together. What we know is that stress can lead to sleep problems, while at the same time turning your body in a fat conserving, eating machine. Not only do you eat more when you are awake past your normal bedtime, the calories you do eat are sequestered as fat and only reluctantly burned due to the elevated cortisol that accompanies your stress and sleeplessness.
The circle is complete when the lack of sleep leads to fatigue on the job, which makes you less effective and puts extra pressure on you to keep up your performance even though you’re tired. All this simply adds more stress.
If you’re having trouble controlling your weight or if it seems that your diet just isn't working, take a long hard look at your life. Life today is full of stress and breaking free is an important first step toward improving your overall health, fitness and quality of life.