Binge-eating mice reveal obesity clues

April 9, 2018, Center for Genomic Regulation
Chocolate bar similar to the ones used in this study. Credit: CC0

Obesity is a growing issue in many countries, accelerated by easy access to calorie-dense foods that are pleasurable to eat (known as an 'obesogenic environment'). But while it's clear that eating too much leads to weight gain, little is known about the underlying behaviours that lead to overeating.

To mimic this obesogenic environment, the teams led by Mara Dierssen at CRG and Rafael Maldonado at UPF offered mice the option of a high-fat 'cafeteria' or a mixture of chopped-up commercial chocolate bars alongside their regular lab chow, before carrying out a detailed analysis of the animals' activity and feeding . Their results have been published in two back-to-back articles in the journal Addiction Biology.

Working together with Cedric Notredame (CRG) and Elena Martín-García (UPF), the scientists found that as well as becoming obese, the mice started very early to show the signs of addiction-like behaviour and binge-eating in response to these enticing foods.

For example, when offered chocolate for just one hour per day, the animals will compulsively 'binge', consuming as much chocolate in one hour as they would over a whole day if it was continually available. They also showed inflexible behaviours, similar to those seen in addiction, choosing to wait for chocolate while ignoring freely available standard chow. Yet, at the same time, the chocolate did not seem to satiate hunger as well as regular food.

The team found that animals on the high fat or diet also changed their daily routines. They were more likely to eat during the daytime - mice are usually nocturnal and feed at night - and they ate shorter more frequent 'snacks' rather than larger, longer-spaced meals.

A major problem in treating obesity is the high rate of relapse to abnormal food-taking habits after maintaining an energy balanced diet. The scientists evaluated this relapse and found that extended access to hypercaloric diets impairs the control of food seeking behaviour and has deleterious effects on learning, motivation and behavioural flexibility.

"Our results revealed that long-term exposure to hypercaloric diets impair the ability to control eating behaviour leading to negative effects on the cognitive processes responsible for a rational control of " says Maldonado, head of the Neuropharmacology Laboratory at UPF.

"Obesity is not just a metabolic disease - it is a behavioural issue. People who are overweight or obese are usually told to eat less and move more, but this is too simplistic." explains Mara Dierssen, group leader of the Cellular and Systems Neurobiology laboratory at CRG. "We need to look at the whole process. By understanding the behaviours that lead to obesity and spotting the tell-tale signs early, we could find therapies or treatments that stop people from becoming overweight in the first place."

The scientists are now expanding their research to larger numbers of animals and they are also planning a study to look at addiction-like behaviours in obese people to see how well their results translate to humans.

"It is very hard to lose weight successfully, and many people end up trapped in a cycle of yo-yo dieting," Dierssen explains. "We need to focus on preventing , and this study shows us that understanding and modifying behaviour could be the key", as Maldonado states "these studies reveal the major behavioural and cognitive changes promoted by hypercaloric intake, which could be crucial for the repeated weight gain and the difficulties to an appropriate diet control".

Explore further: Beware of palm oil in your Valentine's chocolate

More information: Jose Espinosa-Carrasco et al, Time-course and dynamics of obesity-related behavioral changes induced by energy-dense foods in mice, Addiction Biology (2018). DOI: 10.1111/adb.12595

Related Stories

Beware of palm oil in your Valentine's chocolate

February 13, 2018
A diet rich in saturated fat and sugar not only leads to obesity, it creates inflammation in the nucleus accumbens, a part of the brain that controls mood and the feeling of reward. And this inflammation can lead to depressive, ...

Does good-tasting food cause weight gain?

December 15, 2016
Does eating good-tasting food make you gain weight? Despite the common perception that good-tasting food is unhealthy and causes obesity, new research from the Monell Center using a mouse model suggests that desirable taste ...

Obesity prevented in mice fed high-fat diet

December 5, 2017
Researchers at Washington University School of Medicine in St. Louis have identified a way to prevent fat cells from growing larger, a process that leads to weight gain and obesity. By activating a pathway in fat cells in ...

Why your subconscious makes you crave 'naughty' foods

July 21, 2017
The UK's diet industry is thriving to say the least. More than half of British adults try to lose weight by controlling their calorie intake each year. Unfortunately, losing weight is not as easy as turning down a biscuit, ...

Alternating diet between high fat, balanced may help control obesity, study finds

May 25, 2016
Researchers at the University of Georgia's College of Pharmacy have discovered that alternating between a high fat and a more nutritionally balanced diet at regular intervals may help prevent or treat obesity and its associated ...

Can believing you are a food addict affect your eating behavior?

May 5, 2016
Researchers from the University of Liverpool have published a paper regarding their work on how beliefs about food addiction can affect eating behaviour.

Recommended for you

Early postpartum opioids linked with persistent usage

December 14, 2018
Vanderbilt researchers have published findings indicating that regardless of whether a woman delivers a child by cesarean section or by vaginal birth, if they fill prescriptions for opioid pain medications early in the postpartum ...

Drug wholesalers drove fentanyl's deadly rise, report concludes

December 4, 2018
Fentanyl, a powerful synthetic opioid implicated in nearly 29,000 overdose deaths in the United States last year, most likely spread because of heroin and prescription pill shortages, and also because it was cheaper for drug ...

College students choose smartphones over food

November 16, 2018
University at Buffalo researchers have found that college students prefer food deprivation over smartphone deprivation, according to results from a paper in Addictive Behaviors.

Drug overdose epidemic goes far beyond opioids, requires new policies

November 7, 2018
Most government-funded initiatives to address the overdose epidemic in the United States have targeted opioids specifically and have neglected other drugs that are increasingly implicated in overdoses, such as cocaine and ...

Cocaine adulterant may cause brain damage

November 1, 2018
People who regularly take cocaine cut with the animal anti-worming agent levamisole demonstrate impaired cognitive performance and a thinned prefrontal cortex. These findings from two recent studies at the University of Zurich ...

Poverty blamed on widening north-south gap in young adult deaths in England

November 1, 2018
A major study of mortality across England led by University of Manchester data scientists blames socioeconomic deprivation for sharp rises in deaths among 22 to 44-year-olds living in the North of England.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.