Stress tempts you to eat more

Especially hormons increase the desire to eat when the body is stressed.

Stressed out people like to grab a bite of chips or chocolate when everyday problems pile up. Especially women often complain about comfort eating because of sorrow or discomfort - as if the world would seem brighter after a chocolate bar. It is a fact that many people in Germany are "constantly under stress" and feel burnt out. In those moments, comfort often seems to come from the kitchen. Overweight is the result.

Stress is an adjustment reaction in three phases

Stress is not a phenomenon of the present but an adjustment reaction formed by evolution in response to external circumstances and dangerous situations. Even in primeval times stress allowed us to perform at our highest level in flight or fight situations in order to secure our survival. The same mechanisms are still effective today; the fight for survival however mainly takes place in people's heads in the present.

A stress situation can be broken down into three phases: at first our body is put into alert. The blood pressure rises, the heart almost jumps out of your chest and your senses are sharpened. The hormones adrenalin and noradrenalin mobilise the organism for the impending fight situation. During the resistance phase the same hormones also suppress the hunger feeling. Who thinks of eating while being excited!

The body wants to recuperate the energy consumed during the alarm situation: it craves sweet, fat and salty food in order to balance out the lost energy as quickly as possible. As prehistoric men we would have lost quite a bit of salt and burnt many calories during the fight or flight because of the physical strain. Our 21st century body still thinks of that. It demands sweets, chips and fast food. The hormone cortisol which is produced in the adrenal glands is responsible for those cravings. It prepares the body for long term adjustment to stressfull situations. In contrast to the appetite suppressing hormones such as adrenalin it circulates and works significantly longer since it has to be released in the liver. Lingering cortisol is connected with the appetite after stressfull life experiences knows Christian Schinke, doctoral candidate at the clinic for neurology and the Integrated Research and Treatment Center AdiposityDiseases: "Cortisol causes disappearance of appetite inhibitions during the relaxation phase after stress," explains the young medical student. Christian Schinke researches the topic "the dynamic of the stress axis in obese patients" at the IFB in a trial initiated by Prof. Swen Hesse and private lecturer Dr. Florian Then Bergh in cooperation of the institute for nuclear medicine and the clinic for neurology.

The Leipzig scientists around Prof. Hesse therefore want to investigate the stress reaction in morbidly obese people more closely in order to find out how stress contributes to overweight. An exciting result was that the morbidly obese test persons showed cortisol levels during stress that exceeded those of normalweight test persons fivefold: "In contrast to the normalweight participants the adipose test persons showed an overstimulisation of the stress axis or a veritable overdrive of stress homones that were released at a higher rate and also used quicker," the soon-to-be physician explains. So it is no wonder that those cortisol attacks are accompanied by binge eating. It is a fact that the reaction of obese people to stress is more extreme than with normalweight people. More examinations are necessary in order to fully disclose how this overreaction comes to exist. "For that we have to find out which role neurotransmitters such as serotonine and noradrenalin play during the overstimulisation of the stress axis. And for that we have to carry out more PET scan examinations. It is going to be extremely interesting as soon as we get the results about the transmitter activity from the nuclear medical examinations of the PET," emphasises Christian Schinke .

One thing is for sure: In order to counteract the negative effects of stress it is helpfull to remember the original function of the reaction: fight or flight. Exercise not only lessens depression but it also has a positive effect on the feeling of stress and the weight.

Annekathrin Härter

Keywords: causes of obesity, psyche