(Press-News.org) SAN FRANCISCO--Insufficient sleep may contribute to weight gain and obesity by raising levels of a substance in the body that is a natural appetite stimulant, a new study finds. The results were presented today at The Endocrine Society's 95th Annual Meeting in San Francisco.
The researchers found that when healthy, lean, young adults received only 4.5 hours of sleep a night, they had higher daytime circulating, or blood, levels of a molecule that controls the pleasurable aspects of eating, compared with when they slept 8.5 hours.
"Past experimental studies show that sleep restriction increases hunger and appetite," said Erin Hanlon, PhD, research associate (assistant professor) at the University of Chicago's Section of Endocrinology, Diabetes and Metabolism. "The mechanism for overeating after inadequate sleep may be an elevation in this endocannabinoid molecule, called 2-arachidonoylglycerol, or 2-AG."
With colleagues from the University of Chicago Medicine and the Medical College of Wisconsin in Milwaukee, Hanlon studied nine subjects with an average age of 23 years. The subjects spent six nights in a sleep lab and then another six nights there at least a month later. In a random order, the subjects were allowed to sleep from 11 p.m. to 7:30 a.m. ("normal sleep – 8.5 hours in bed") during one testing period and from 1 to 5:30 a.m. ("partial sleep restriction – 4.5 hours in bed") during the other testing period. During waking hours, the subjects ate a controlled number of calories based on their height and weight.
After the second night of each sleep condition, the researchers took blood samples from the subjects at one-hour intervals for 24 hours. Using a highly accurate laboratory assay, they analyzed the samples for 2-AG, a component of the endocannabinoid system. Found throughout the body, this system plays an important role in the signaling of rewarding events and one's enjoyment of eating, similar to the cannabinoids in marijuana, Hanlon said.
Levels of 2-AG levels were the lowest halfway through sleep and the highest in the early afternoon, "when the pleasurable properties of food would be most beneficial," Hanlon said. She reported that the afternoon peak of 2-AG was even higher when the study participants had partial sleep restriction than when they had normal sleep.
The study results suggest that the increased hunger and appetite that subjects in previous studies have reported after sleep restriction might be due to increases in circulating 2-AG, she said.
"These findings," Hanlon said, "are highly relevant to millions of individuals who are at an increased risk of obesity and its health consequences because of chronic short sleep or sleep disruption."
This study received funding from the National Institutes of Health, the Department of Defense Peer Reviewed Medical Program and the Advancing a Healthier Wisconsin endowment fund of the Medical College of Wisconsin.
###
Founded in 1916, The Endocrine Society is the world's oldest, largest and most active organization devoted to research on hormones and the clinical practice of endocrinology. Today, The Endocrine Society's membership consists of over 16,000 scientists, physicians, educators, nurses and students in more than 100 countries. Society members represent all basic, applied and clinical interests in endocrinology. The Endocrine Society is based in Chevy Chase, Maryland. To learn more about the Society and the field of endocrinology, visit our site at http://www.endocrine.org. Follow us on Twitter.
Too little sleep may trigger the 'munchies' by raising levels of an appetite-controlling molecule
2013-06-17
ELSE PRESS RELEASES FROM THIS DATE:
Weight loss improves memory and alters brain activity in overweight women
2013-06-17
SAN FRANCISCO-- Memory improves in older, overweight women after they lose weight by dieting, and their brain activity actually changes in the regions of the brain that are important for memory tasks, a new study finds. The results were presented today at The Endocrine Society's 95th Annual Meeting in San Francisco.
"Our findings suggest that obesity-associated impairments in memory function are reversible, adding incentive for weight loss," said lead author Andreas Pettersson, MD, a PhD student at Umea University, Umea, Sweden.
Previous research has shown that obese ...
Being overweight linked to excess stress hormones after eating
2013-06-17
SAN FRANCISCO-- Overweight and obese men secrete greater amounts of stress hormones after eating, which may make them more susceptible to disease, a new observational study finds. The results will be presented Saturday at The Endocrine Society's 95th Annual Meeting in San Francisco.
Excess weight and obesity are a global health problem, and medical researchers are seeking different approaches to reduce the burden of disease. One way to do this is by identifying differences in hormonal regulation between overweight and lean people in response to various situations, including ...
The Rett Syndrome protein surrenders some of its secrets
2013-06-17
Discovery of a mutant gene responsible for a disease is a milestone, but for most conditions, it may be only a first step towards a treatment or cure. Understanding Rett Syndrome, an autism spectrum disorder, is further complicated by the fact that the implicated gene controls a suite of other genes. Two papers, published in today's Nature Neuroscience and Nature, reveal key steps in how mutations in the gene for methyl CpG-binding protein (MECP2) cause the condition. The Rett Syndrome Research Trust (RSRT) funded this work with generous support from partners Rett Syndrome ...
Drug boosts fat tissue's calorie-burning ability in lab
2013-06-17
SAN FRANCISCO-- A drug that mimics the activity of thyroid hormone significantly increases the amount of energy burned by fat tissue and promotes weight loss, an animal study of metabolism finds. The results were presented Sunday at The Endocrine Society's 95th Annual Meeting in San Francisco.
Humans and other mammals have two kinds of fat, or adipose, tissue, which are referred to by color: white or brown. White adipose tissue, or WAT, has low energy-burning capacity. Because of this, WAT is associated with weight gain and obesity, as well as other conditions related ...
Testosterone therapy improves sexual function after uterus and ovary removal
2013-06-17
SAN FRANCISCO-- High doses of testosterone significantly improve sexual function among women who have had their uterus and ovaries surgically removed, a clinical study demonstrates. The results were presented Sunday at The Endocrine Society's 95th Annual Meeting in San Francisco.
Surgical removal of the uterus, or hysterectomy, and the ovaries, which is called oophorectomy, is performed to treat various diseases, including cancer. Hysterectomy is also performed as an elective sterilization, usually among older women, and may be combined with oophorectomy if ovarian disease ...
Insulin resistance linked to weaker bones
2013-06-17
SAN FRANCISCO-- Reduced effectiveness of the hormone insulin, or insulin resistance, is associated with weakened bones, a clinical study shows. The results were presented Sunday at The Endocrine Society's 95th Annual Meeting in San Francisco.
In the United States, the incidence of diabetes is quickly mounting. Between the years of 1980 and 2011, the number of cases diagnosed jumped from about 6 million to nearly 21 million, according to statistics from the Centers for Disease Control and Prevention.
Type 2 diabetes is the result of insulin resistance, which causes cells ...
Skipping breakfast may make obese women insulin resistant
2013-06-17
SAN FRANCISCO—- Overweight women who skip breakfast experience acute, or rapid-onset, insulin resistance, a condition that, when chronic, is a risk factor for diabetes, a new study finds. The results, which were presented Sunday at The Endocrine Society's 95th Annual Meeting in San Francisco, suggest that regularly skipping breakfast over time may lead to chronic insulin resistance and thus could increase an individual's risk for type 2 diabetes.
"Our study found that acute insulin resistance developed after only one day of skipping breakfast," said the study's lead author, ...
Short-term antidepressant use, stress, high-fat diet linked to long-term weight gain
2013-06-17
SAN FRANCISCO—- Short-term use of antidepressants, combined with stress and a high-fat diet, is associated with long-term increases in body weight, a new animal study finds. The results were presented Sunday at The Endocrine Society's 95th Annual Meeting in San Francisco.
"Our study suggests that short-term exposure to stress and antidepressants, rather than a high-calorie, high-fat diet alone, leads to long-term body weight gain, accompanied with increased bone and spleen weights," said study lead author Suhyun Lee, a PhD candidate in the medical sciences at the John ...
Father's diet before conception affects offspring's body fat in mice
2013-06-17
SAN FRANCISCO—- When fathers eat a high-fat diet before conception of offspring, the male offspring have increased body weight after weaning and high body fat in midlife despite eating a low-fat diet, a new study in mice finds. The results were presented Sunday at The Endocrine Society's 95th Annual Meeting in San Francisco.
"Many researchers have studied the effects of maternal diet on the risk of obesity in their children. We found that the father's diet also affects the offspring in ways that are inherited," said the study's principal investigator, Felicia V. Nowak, ...
JCI early table of contents for June 17, 2013
2013-06-17
Scouring the genome of adenoid cystic carcinoma
Adenoid cystic carcinoma (ACC) is a slow-growing and often fatal malignancy that can occur at multiple organ site, but is most frequently found in the salivary glands. The primary treatment is surgical removal; however, the majority of patients develop metastatic disease. In this issue of the Journal of Clinical Investigation, researchers led by Andrew Futreal at the Wellcome Trust Sanger Institute in Cambridge, MA, performed a type of genetic sequencing known as whole exome sequencing of 24 ACC cases. They identified a genetic ...