More likely than not, you’ve heard the latest bulletins – more sleep might be causing you to lose weight. Wouldn’t that be great? Just lay your head down to that pillow a little longer each night and you could be facing a slimmer waistline in the morning. While it isn’t quite that easy, knowing a little more about the effects of sleep may help you decide if more sleep would be helpful to your weight loss efforts.

As you may know, though probably never thought about, sleep decreases appetite making it possible to spend ten or more hours between dinner and breakfast the following morning without eating. Ten hours without eating is considerably more difficult to achieve when we are awake. From a behavioral perspective, if we reduce the amount of time sleeping, this leaves more hours without the appetite suppression of sleep and so we are likely to eat more. It is also possible that weight gain may simply result from the food choices we make when we are tired. Without enough sleep, we often don’t want to go to the trouble of cooking a healthy breakfast, lunch and dinner. Instead, we grab fast food, take out and delivery. We are too exhausted to make the right choices in our diet. How much easier is it to just sit in your car while someone else slings around some bacon in order to create your egg and biscuit sandwich?

Although behavioral components are involved, other chemical reasons are likely to drive weight gain for sleep deprived individuals. One theory centers on the stress hormone cortisol. Cortisol is produced in larger amounts when you are exposed to light. It helps to keep us active during the daylight hours and levels decrease toward the evening to allow us to rest and recover during sleep. One of its roles is to help regulate energy levels in the body. Cortisol operates on fat and carbohydrate metabolism as well as regulating insulin and blood sugar levels.  To help create energy, cortisol stimulates appetite and works to store excess food as fat for later use.

Artificial light sources and stress also stimulate cortisol release. So, the more you sit in front of a television, lamp, or computer or the more you engage in activities such as work that can cause stress, the more you produce cortisol and the hungrier you get.

Yet another chemical interaction sleep has is its relationship with the hunger hormones leptin and ghrelin.  Leptin is produced by fat cells as a signal that enough fat is stored and works to suppress appetite. Ghrelin is produced in the stomach when it is empty and let’s you know you are hungry.  Lack of sleep decreases leptin and increases ghrelin levels giving your body powerful signals of hunger even though you may not need additional food.

The interaction between sleep and weight is complex and being sleep deprived is only one factor contributing to weight gain.  However, it is one that is relatively easily corrected simply by trying to sleep 7 to 8 hours each night.