Getting enough sleep?

The advantages of getting enough restful sleep are numerous and well known, but did you know a lack of proper sleep could be making you fat? This is true for more than one reason, scientists say.

Slimtrack users know that when your energy intake is regularly greater than your energy expenditure, you will gain weight, and vice versa. “But,” says dr. Kristen Knutson of the University of Chicago, “an additional factor may be inadequate sleep.”

Knutson was the lead researcher of a study into this subject, and the results were recently published in a special issue of the American Journal of Human Biology. The study explored how lack of sleep can cause weight gain because it impacts on appetite regulation, impairs glucose metabolism and increases blood pressure.

“A review of the evidence shows how short or poor quality sleep is linked to increased risk of obesity by de-regulating appetite, leading to increased energy consumption,” Knutson says.

Other research has found similar links between poor quality sleep and weight problems. This includes a 2008 study by professor Jacques Montplaisir of the Université de Montréal in Canada, who is also the director of Sleep Disorders Center at Sacré-Coeur Hospital. He found that the relationship between sleep and weight could be explained by a change in the secretion of hormones that’s brought on by lack of sleep. “When we sleep less, our stomach secretes more of the hormone that stimulates appetite,” Montplaisir was quoted as saying by www.sciencedaily.com. “And we also produce less of the hormone whose function is to reduce the intake of food.”

Another study found that people who don’t get enough sleep are less likely to cook their own meals and consequently eat more fast food. The resulting lack of nutritional value in their meals may cause weight and other health problems in the long run.

Knutson’s study found an association between getting fewer than six hours sleep and increased body mass index (BMI) or even obesity. Sleep restriction experiments also confirmed that inadequate sleep causes more secretion of two “signal hormones”: Ghrelin, which increases appetite, and leptin, which plays a key role in regulating energy intake and energy expenditure in the human body.

The result of this sleep restriction is increased food intake without the compensating energy expenditure. This in turn leads to weight gain.

The United States has a well-documented obesity epidemic, and it may be no coincidence that it also has an estimated 18% of its adult population that gets less than 6 hours of sleep a night. While the science of sleep is not well developed in South Africa, international studies estimate that around 10% of the world’s population has a diagnosable sleep disorder.

If you suspect you may have a sleep disorder, visit the South African Sleep Centre Network. “Sleep disorders are usually effectively treatable, but due to a lack of education and training, recognition of these disorders by medical professionals is still very low,” the Centre says on its website.