Sleeping Away Unwanted Pounds?

Not that my wife needs to lose weight, but if she could lose weight and do so while sleeping it would be akin to winning the lottery. Effortless weight-loss while sleeping would certainly be a boon to millions of Americans.

According to an article on WebMD.com, as wild as the idea sounds, more and more research is making seemingly legitimate correlations between sleep and weight. Researchers at the Sleep Medicine Program at the New York University School of Medicine in New York City say that how much you sleep and quite possibility the quality of your sleep may work in tandem to affect the hormonal activity tied to our appetites.

Researchers are discovering that sleep and sleep disruption do remarkable things to the body -- including possibly influencing a person's weight -- that according to a study conducted at the Sleep Medicine Program at the New York University School of Medicine.

While doctors have long known that many hormones are affected by sleep, it wasn't until recently that appetite entered the picture. What brought it into focus, was research on the hormones leptin and ghrelin - both of which can influence our appetite. And studies show that production of both may be influenced by how much or how little we sleep.

According to an explanation on WebMD.com taken from the Atlanta School of Sleep Medicine, leptin and ghrelin work in a kind of "checks and balances" system to control feelings of hunger and fullness. Ghrelin -- which is produced in the gastrointestinal tract -- stimulates appetite, while leptin -- produced in fat cells -- sends a signal to the brain when you are full.

The connection all this has with sleep is that when you don't get enough sleep, it drives leptin levels down, which means you don't feel as satisfied after you eat. Lack of sleep also causes ghrelin levels to rise, which means your appetite is stimulated, so you want more food.

Combine these reactions and you're setting yourself up for overeating -- which in turn has the potential for weight gain.

Two studies conducted at the University of Chicago in Illinois and at Stanford University in California explored the relationship between the hormones leptin and ghrelin and their link to overeating:

According to webmd.com, In the Chicago study, doctors measured levels of leptin and ghrelin in 12 healthy men. They also noted their hunger and appetite levels. Soon after, the men were subjected to two days of sleep deprivation followed by two days of extended sleep. During this time doctors continued to monitor hormone levels, appetite, and activity.

So what happened? When sleep was restricted, leptin levels went down and ghrelin levels went up. Not surprisingly, the men's appetite also increased proportionally. Their desire for high carbohydrate, calorie-dense foods increased by a whopping 45%.

But the study at Stanford shed even more light on the subject: in this research -- a joint project between Stanford and the University of Wisconsin -- about 1,000 volunteers reported the number of hours they slept each night. Doctors then measured their levels of ghrelin and leptin, as well as charted their weight. Those who slept less than eight hours a night not only had lower levels of leptin and higher levels of ghrelin, but they also had a higher level of body fat. What's more, that level of body fat seemed to correlate with their sleep patterns. Specifically, those who slept the fewest hours per night weighed the most.

So - based on these studies - it would seem logical that getting more sleep just might be the answer to America's obesity problem.

So why does low leptin seem to cause weight gain in some folks while allowing others to lose weight? According to an article in the Journal of Clinical Endocrinology and Metabolism, one theory says that it may not be the level of this hormone that matters so much as a person's individual response to it. In much the same way that obese people can become resistant to insulin, some individuals may be resistant to the fullness signal that leptin sends to the brain.

It's like the body is trying to tell them to stop eating, but their brain just isn't getting the message.

Others voice the opinion that the overall response to leptin may be more individual than we think. Experts quoted in the American Journal of Physiology -- Heart and Circulatory Physiology say our environment, dietary habits, exercise patterns, personal stress levels, and particularly our genetics may all influence the production of leptin and ghrelin, as well as our response to them.

Until doctors do know more, most experts agree that if you are dieting, logging in a few extra hours of sleep a week is not a bad idea, particularly if you get six hours of sleep or less a night. You may just discover that you aren't as hungry, or that you have lessened your craving for sugary, calorie-dense foods.

One thing seems certain: when a person is not as tired, they don't need to rely on sweet foods and high carbohydrate snacks to keep them awake -- and that automatically translates into eating fewer calories.

And don't forget: if you exercise regularly you sleep better too.