Brain Disorder That's why overweight people just can not get enough

Possible explanation for the often lack of satiety feeling found by obese people

German researchers have discovered a possible explanation for the often lack of satiety overweight. They found that in the brain of obese people, the production of energy from glucose (sugar) is greatly reduced. Another finding: There is a parallel between overweight and depressive.

Why some people do not get full

Not only in Germany are obese people often stigmatized and marginalized. Obesity has long been a common disease, which is caused by many factors. Some of them have little or no influence. For example, obese people often have a lack of satiety, which, according to scientists, is explained by, among other things, a paralyzing metabolism. Excess pounds may also be responsible for certain intestinal bacteria, as French researchers reported. Scientists from the Department of Psychoneurobiology at the Center for Brain, Behavior and Metabolism (CBBM) of the University of Lübeck have now found another possible explanation for the often absent feeling of satiety overweight.

Researchers have found that in the brain of obese people, the production of energy from glucose (sugar) is greatly reduced. The disturbed energy production of the brain could be an explanation for the often missing satiety feeling overweight. (Image: Kurhan / fotolia.com)

Number of overweight is steadily rising

According to current estimates, obesity affects approximately 2.2 billion adults worldwide, 650 million of whom suffer from its extreme form - obesity, according to a statement from the University of Lübeck.

In the age group between five and 19 years, overweight according to the World Health Organization (WHO) affects 340 million and at age under five still 41 million children.

In Germany alone, the figure amounts to around 60 percent of the population, now more men than women.

Common weight loss treatment programs are based on diet plans, diet changes, calorie calculators, sports programs, etc., and are currently not known to be effective in the long term.

In the long term, in the majority of cases, they lead to a renewed weight, often even beyond the initial situation (so-called yo-yo effect). The number of overweight people therefore continues to rise.

Disruption of energy homeostasis

An explanation for this development researchers see in a disturbance of energy homeostasis in the brain.

A team led by Prof. Kerstin Oltmanns from the University of Lübeck in 2010 was able to prove that there is a connection between increasing body weight and reduced energy content in the human brain.

The cause of the lowered energy status was completely unclear. One only knew that a high cerebral energy content triggers satiety. Overweight people often report that they are not aware of satiety.

Changes in the energy status of the brain are investigated

An interdisciplinary working group of the Lübeck section for psychoneurobiology under the direction of the graduate psychologist Ewelina K. Wardzinski and Prof. Oltmanns in a recent study in obese and normal-weight men by intravenous glucose infusion, the blood sugar - and thus the sugar intake for energy production in the brain - experimentally increased and studied changes in the energy status of the brain.

This was done using 31P magnetic resonance spectroscopy, a method that very few research centers worldwide have.

In the normal-weight group, the brain energy level increased immediately after glucose administration, while no changes were seen in the obese study participants.

Only after a strong increase of the blood sugar by the infusion a small increase took place also in the brain of the overweight study participants.

The researchers recently published their findings in the journal Metabolism.

Overweight as a psychoneurobiological disorder?

"The results of this study show that in obese people there is a disruption of energy production in the brain," explains psychologist Wardzinski.

"This disorder may explain the chronically reduced cerebral energy status in those affected and also why obese people often feel no sense of satiety. Then the brain is hungry, so to speak. "

Interestingly, parallels to mental illnesses affecting mood and feelings are found in terms of decreased brain energy levels.

People with depression also show a reduced brain energy content. Similar to mental illness, behavioral therapy rather than diet is apparently also successful in overweight.

A behavioral learning program developed especially for obese people leads to an improvement in the perception of satiety, reduction of food intake and thus weight loss, as the first interim results of an ongoing study show.

"Apparently, mental health, brain energy metabolism and body weight regulation are closely related, which has to be taken into account if you want to permanently lose weight," says Prof. Oltmanns. (Ad)