Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

After overeating, we don’t compensate by eating less

16.08.2005


If you binged for two weeks while on vacation and gained 5 pounds, would you be biologically primed to eat less to compensate and shake off the excess weight? No, suggests a new Cornell University study.

When a group of 12 normal-weight men and women, average age 31, agreed to overeat by 35 percent for two weeks, they gained an average of 5 pounds, half of it body fat. When they were permitted to return to their normal eating behavior, they did not spontaneously cut back on their normal food intake, even after the two weeks of "feeling stuffed." Rather, they ate just as much as they did before the overeating period, as measured by the researchers during the two weeks before their binge began.

"The study suggests that eating behavior does not normally respond to internal cues, such as physiological mechanisms involved in the regulation of body weight, but to external cues," said David Levitsky, professor of nutritional sciences and of psychology at Cornell. "In other words, when the subjects returned to the same environment -- in this case our eating lab -- they returned to their same eating patterns, regardless of any biological signals."



The results add to the growing evidence that environmental cues, especially portion size, appear to be a major determinant of how much we eat, he said. This finding runs counter to the current view that food intake is largely determined by biological mechanisms.

The study is published in Physiology and Behavior (Vol. 84 (5), pp. 669-675) and was co-authored by Eva Obarzanek, a nutritionist for the National Heart, Lung and Blood Institute of the National Institutes of Health, Gordana Mrdjenovic, Cornell Ph.D. ’00, and Barbara Strupp, associate professor of nutritional sciences at Cornell.

Despite not eating less or exercising more after gaining weight, the participants still lost about half of their weight gain in the three weeks after the overeating phase because their metabolic rate spontaneously increased. "You burn more energy simply by carrying around additional weight," Levitsky said. "The spontaneous increase in metabolic rate that we found in the subjects after overeating was remarkably consistent with a comparable overfeeding study in animals, as well as with other studies with humans and overeating."

He plans to conduct a study in the fall to examine how much additional energy is expended when carrying around extra weight. It is well known, he said, that obese people have higher energy expenditures than nonobese people, and his study is an example of weight being regulated passively without any control of food intake.

Levitsky has been exploring predictors of food intake for several years. A number of his previous studies found that the amount animals and people eat is strongly determined by portion size, and that eating between meals, or eating a very large or very small (or no) previous meal does not influence how much is eaten at the next meal.

"Consistently, we find that how much people eat is in direct relation to how much they are served, the variety of foods offered and the number of people with whom they eat," Levitsky said.

Nicola Pytell | EurekAlert!
Further information:
http://www.cornell.edu

More articles from Studies and Analyses:

nachricht Amputees can learn to control a robotic arm with their minds
28.11.2017 | University of Chicago Medical Center

nachricht The importance of biodiversity in forests could increase due to climate change
17.11.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>