Study links evening blue light exposure to increased hunger

Manipulation of light exposure may be a novel method of altering food intake and metabolism

2014-06-02

(Press-News.org) DARIEN, IL – A new study suggests that blue-enriched light exposure immediately before and during the evening meal may increase hunger and alter metabolism.

Results show that blue-enriched light exposure, compared with dim light exposure, was associated with an increase in hunger that began 15 minutes after light onset and was still present almost two hours after the meal. Blue light exposure also decreased sleepiness and resulted in higher measures of insulin resistance.

"It was very interesting to observe that a single three-hour exposure to blue-enriched light in the evening acutely impacted hunger and glucose metabolism," said study co-author Ivy Cheung, a doctoral candidate in the Interdepartmental Neuroscience program at Northwestern University in Chicago, Illinois. "These results are important because they suggest that manipulating environmental light exposure for humans may represent a novel approach of influencing food intake patterns and metabolism."

The research abstract was published recently in an online supplement of the journal Sleep and will be presented Tuesday, June 3, in Minneapolis, Minnesota, at SLEEP 2014, the 28th annual meeting of the Associated Professional Sleep Societies LLC.

The study group comprised 10 healthy adults with regular sleep and eating schedules who received identical carbohydrate-rich isocaloric meals. They completed a four-day protocol under dim light conditions, which involved exposure to less than 20 lux during 16 hours awake and less than 3 lux during eight hours of sleep. On day three they were exposed to three hours of 260 lux, blue-enriched light starting 10.5 hours after waking up, and the effects were compared with dim light exposure on day two.

Cheung noted that more research is needed to determine the mechanisms of action involved in the relationship between light exposure, hunger and metabolism.

INFORMATION: The research was performed under the supervision of Drs. Phyllis C. Zee, MD, PhD and Kathryn J. Reid, PhD, in the Circadian Rhythms and Sleep Research Laboratory at Northwestern University.

For a copy of the abstract, "Evening Blue-Enriched Light Exposure Increases Hunger and Alters Metabolism in Normal Weight Adults," or to arrange an interview with Ivy Cheung or an AASM spokesperson, please contact AASM Communications Coordinator Lynn Celmer at 630-737-9700, ext. 9364, or lcelmer@aasmnet.org.

Established in 1975, the American Academy of Sleep Medicine (AASM) improves sleep health and promotes high quality patient centered care through advocacy, education, strategic research, and practice standards. With about 9,000 members, the AASM is the largest professional membership society for physicians, scientists and other health care providers dedicated to sleep medicine. For more information, visit http://www.aasmnet.org.

ELSE PRESS RELEASES FROM THIS DATE:

Astronomers find a new type of planet: The 'mega-Earth'

2014-06-02

Astronomers announced today that they have discovered a new type of planet - a rocky world weighing 17 times as much as Earth. Theorists believed such a world couldn't form because anything so hefty would grab hydrogen gas as it grew and become a Jupiter-like gas giant. This planet, though, is all solids and much bigger than previously discovered "super-Earths," making it a "mega-Earth." "We were very surprised when we realized what we had found," says astronomer Xavier Dumusque of the Harvard-Smithsonian Center for Astrophysics (CfA), who led the data analysis and made ...

'Neapolitan' exoplanets come in three flavors

2014-06-02

The planets of our solar system come in two basic flavors, like vanilla and chocolate ice cream. We have small, rocky terrestrials like Earth and Mars, and large gas giants like Neptune and Jupiter. We're missing the astronomical equivalent of strawberry ice cream - planets between about one and four times the size of Earth. NASA's Kepler mission has discovered that these types of planets are very common around other stars. New research following up on the Kepler discoveries shows that alien worlds, or exoplanets, can be divided into three groups - terrestrials, gas giants, ...

Harsh space weather may doom potential life on red-dwarf planets

2014-06-02

Life in the universe might be even rarer than we thought. Recently, astronomers looking for potentially habitable worlds have targeted red dwarf stars because they are the most common type of star, comprising 80 percent of the stars in the universe. But a new study shows that harsh space weather might strip the atmosphere of any rocky planet orbiting in a red dwarf's habitable zone. "A red-dwarf planet faces an extreme space environment, in addition to other stresses like tidal locking," says Ofer Cohen of the Harvard-Smithsonian Center for Astrophysics (CfA). Cohen ...

Because you can't eat just one: Star will swallow two planets

2014-06-02

Two worlds orbiting a distant star are about to become a snack of cosmic proportions. Astronomers announced today that the planets Kepler-56b and Kepler-56c will be swallowed by their star in a short time by astronomical standards. Their ends will come in 130 million and 155 million years, respectively. "As far as we know, this is the first time two known exoplanets in a single system have a predicted 'time of death,'" says lead author Gongjie Li of the Harvard-Smithsonian Center for Astrophysics (CfA). She presented her research today in a press conference at a meeting ...

Long-term results encouraging for combination immunotherapy for advanced melanoma

2014-06-02

New Haven, CT — The first long-term follow-up results from a phase 1b immunotherapy trial combining drugs for advanced melanoma patients has shown encouraging results — long-lasting with high survival rates — researchers report. First author Mario Sznol, M.D., professor of medical oncology at Yale Cancer Center, is presenting the updated data at the 2014 annual conference of the American Society of Clinical Oncology (ASCO) in Chicago. Sznol, clinical research leader of the melanoma research program at Yale Cancer Center, was the senior author on the original study of ...

Does your stomach bacteria protect you from obesity?

2014-06-02

The germ Helicobacter pylori is the cause of most stomach ulcers, but new research in Alimentary Pharmacology & Therapeutics suggests that treating the bacteria is linked to weight gain. It is estimated that 50% of the global population may be infected with H. pylori; however, only 20% of infected people experience symptoms. New evidence suggests that patients treated for the infection developed significant weight gain compared to subjects with untreated H. pylori colonization. By reviewing data taken from forty-nine studies with data from ten European countries, Japan, ...

Britain's urban rivers cleanest in 20 years

2014-06-02

Scientists from Cardiff University have found that Britain's urban rivers are the cleanest they've been in over two decades. The 21-year study of over 2300 rivers measured the presence of clean-river invertebrates - a yardstick for river health – which during the days of heavy industry and poor sewage treatment had declined considerably, but now appear to be making a comeback. Although climate change has warmed British rivers by around 1-2 degrees over recent decades, the findings suggest that improved pollution control has managed to offset its damaging effects on ...

Cystic fibrosis and diabetes link explained

2014-06-02

Many people with cystic fibrosis develop diabetes. The reasons for this have been largely unknown, but now researchers at Lund University in Sweden and Karolinska institutet have identified a molecular mechanism that contributes to the raised diabetes risk. "The increased risk of diabetes has previously been explained by the fact that cystic fibrosis causes damage to the pancreas, where the blood-sugar regulating hormone insulin is produced. We are the first research group to show that the mutated gene that causes cystic fibrosis also plays an important role in the release ...

Ice Storm Project and maternal stress

2014-06-02

Montreal, June 2, 2014 - A new study finds a link between prenatal maternal stress (PNMS) and the development of symptoms of asthma and autism in children. A team of scientists from The Douglas Mental Health University Institute and from McGill University has been studying women who were pregnant during the January 1998 Quebec ice storm since June of that year and observing effects of their stress on their children's development (Project Ice Storm).The team examined the degree to which the mothers' objective degree of hardship from the storm and their subjective degree ...

Blunting rice disease

2014-06-02

A fungus that kills an estimated 30 percent of the world's rice crop may finally have met its match, thanks to a research discovery made by scientists at the University of Delaware and the University of California at Davis. The research team, led by Harsh Bais, associate professor of plant and soil sciences in UD's College of Agriculture and Natural Resources, has identified a naturally occurring microbe living right in the soil around rice plants — Pseudomonas chlororaphis EA105 — that inhibits the devastating fungus known as rice blast. What's more, the beneficial soil ...

LAST 30 PRESS RELEASES:

A map for single-atom catalysts

What about tritiated water release from Fukushima? Ocean model simulations provide an objective scientific knowledge on the long-term tritium distribution