Fat kids linked to lack of sleep

Soaring levels of obesity might be linked to children sleeping fewer hours at night than they used to, claims Dr Shahrad Taheri of the University of Bristol.

Dr Taheri, reporting in the Archives of Disease in Childhood, blames the increasing availability of computers, mobile phones, TVs and other such gadgets on the diminishing nightly quota of sleep, and suggests they should be banned from children's bedrooms.

Dr Taheri cites the emerging body of research on the impact on the body of a fall in the nightly quota of sleep, which reflects circumstances in real life, rather than sustained sleep deprivation, which tends to be more extreme.

This research shows that shorter sleep duration disturbs normal metabolism, which may contribute to obesity, insulin resistance, diabetes, and cardiovascular disease. Even two to three nights of shortened sleep can have profound effects, the laboratory data suggest.

One study indicated that insufficient sleep at the age of 30 months was associated with obesity at the age of seven, suggesting that this could programme the part of the brain regulating appetite and energy expenditure, says Dr Taheri.

But it is also a problem for teenagers in whom the need for sleep increases during this critical developmental period, he says.

Another piece of research shows that levels of leptin, a hormone produced by fat tissue when energy stores are low, were more than 15% lower in those sleeping five hours compared with those clocking up eight.

Similarly, ghrelin, a hormone released by the stomach to signal hunger was almost 15% higher in those with a five hour sleep quota.

Sleep loss also disturbs other hormones, including insulin, cortisol (stress hormone), and growth hormone, says Dr Taheri, who adds that hormonal changes could boost the desire for calorie rich foods.

And poor sleep sets up a vicious cycle. It leads to fatigue, which leads to reduced levels of physical activity, .which leads to lower energy expenditure, which leads to obesity, which itself leads to poor sleep, explains Taheri.

Dr Taheri acknowledges that the mechanisms behind obesity are likely to be complex. "Sleep is probably not the only answer to the obesity pandemic, but its effect should be taken seriously, as even small changes in energy balance are beneficial," he says. "Good sleep could be promoted by removal of gadget distractions from bedrooms and restricting their use," he suggests.

Source: University of Bristol

Related stories:

New pill increases dreaming sleep
A new sleeping pill that increases dreaming sleep improves memory capacity, according to the results of new research.
Does the lack of sleep make you fat?
The recent rise in obesity may be partly due to the reduced amount of time we spend asleep, according to new research from the University of Bristol, UK.
Dr Shahrad Taheri from Bristol University, and colleagues in the United States, examined the role of two key hormones that are involved in regulating appetite – ghrelin and leptin. Ghrelin increases feelings of hunger while leptin acts to suppress appetite.
Loneliness undermines health as well as mental well-being
Feeling connected to others is vital to a person's mental well-being, as well as physical health, research at the University of Chicago shows.
New master switch found in the brain that regulates appetite and reproduction
Body weight and fertility have long known to be related to each other – women who are too thin, for example, can have trouble becoming pregnant. Now, a master switch has been found in the brain of mice that controls both, and researchers at the Salk Institute for Biological Studies say it may work the same way in humans.
A therapy for baby boomers to sleep on
If you're over 55 and have spent more than a few sleepless nights, you're not alone -- insomnia affects about half of all people over 55 -- but you may also be at increased risk for physical and mental ailments.
Less REM sleep associated with being overweight among children and teens
Children and teens who get less sleep, especially those who spend less time in rapid eye movement (REM) sleep, may be more likely to be overweight, according to a report in the August issue of Archives of General Psychiatry.
Circadian rhythm-metabolism link discovered
UC Irvine researchers have found a molecular link between circadian rhythms – our own body clock – and metabolism. The discovery reveals new possibilities for the treatment of diabetes, obesity and other related diseases.
New approach sheds light on ways Circadian disruption affects human health
Growing evidence indicates that exposure to irregular patterns of light and darkness can cause the human circadian system to fall out of synchrony with the 24-hour solar day, negatively affecting human health — but scientists have been unable to effectively study the relationship between circadian disruptions and human maladies.

News discussion:

Medicine & Health news