Hyperphagia

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Hyperphagia is a phenomenon known as an eating disorder and civilization disease , whereby people eat excessively without feeling hungry, sometimes also chronically.

Research background

Undernourishment, malnutrition and overeating are global problems that have become more relevant. Eating disorders and the comorbidities associated with them make up an ever greater proportion of the total cost of illness. Obesity , in particular , is not always viewed as a disease and, as the cause of many clinical pictures with long-term consequences, is treated with insufficient preventive measures. Overweight and obesity represent a challenge for today's medicine as well as for chemistry research. Even being slightly overweight increases morbidity and mortality by promoting risk factors and metabolic diseases . According to recent studies, the average life expectancy in the presence of obesity is reduced by seven years at the age of 40. The connection between obesity and coronary heart disease , hypertension , lipid metabolism disorders , degenerative joint changes and diabetes mellitus diseases is undisputed. However, despite education about the dangers of overweight and obesity and various campaigns for a healthier lifestyle and diet, the prevalence of obesity has increased in recent years.

Food intake is regulated in a much more complex way than just by peripheral and central mechanisms. It is an interplay of physiological and genetic components, a mixture of lifestyle and psychological factors as well as the composition and palatability of the food offered. Meals are not always due to hunger and appetite , but also to habits , times of the day, stress , convenience, or addiction / lust . The homeostatic influence on food intake can then be limited to the control of energy intake during the meal. Taste and odor sensors in the oronasal area transmit their information via the brain stem and thalamus to the cortex , the limbic system and the lateral hypothalamus . The reward system in the human brain is very complex and consists largely of interactions between the opioid , dopamine and cannabinoid systems . Opiate antagonists reduce the palatability of food in humans without affecting the subjective feeling of hunger.

A lack of dopamine leads to hypophagia in mice . The appetite-increasing effects z. B. of cannabis are known. Its endogenous analogues, the endocannabinoids , also show orexigenic, i.e., appetite-increasing effects. Since leptin to serotonin turnover appears to increase, could theoretically a part of his weight-lowering effects are mediated by serotonin.

Research into causes of addiction triggers in food

In research, various causes are assumed for hyperphagia. Various studies, some of which build on one another, were carried out at the FAU Erlangen-Nürnberg , and these are often cited in the press. In the studies cited in 2013, it was initially shown that the irrepressible desire to eat cannot be attributed to a high proportion of fat and carbohydrates alone. Later it turned out that the ratio of fat and carbohydrates according to the formula 35:45 or 35:50 (fat: carbohydrates) is decisive. Nonetheless, the researchers assume that other factors play a role in many snacks that have this ratio. This results from comparing particularly sought-after foods, such as crisps, with other test foods that have the same addictive ratio. In addition, individual inclinations, constitutions and the personal ability to show restraint played a role. The experiments were carried out initially with rats and later also with humans. At a meeting of the American Chemical Society in New Orleans in April 2013, it was stated that the potato chips examined there must have properties or ingredients that have not yet been defined that have a stimulating effect on the reward system of our brain .

Such research could provide insight into the development of hedonistic hyperphagia. Along with other snacks, potato chips are among those foods that are often consumed without feeling really hungry. However, according to the studies cited above, the high content of fats and carbohydrates is not the main reason for this phenomenon. After eating potato chips, rats in the experiment showed a lot of activity in order to get more chips because the reward center of the brain was activated "as if in a drug intoxication".

The decisive factor of the well-known hyperphagia consists in the fact that this type of eating disorder is not a habit or an attempt to experience a feeling of satiety (e.g. an individual non-existent), but rather eating via the stimulation of the pleasure center itself need is created. In order to avoid such effects, following corresponding further research results, substances could in future be added to foods that block the "pleasure factor" and thus lead to more moderate consumption of the snacks . It would also be beneficial if it were possible to increase cravings for healthy food.

literature

  • Ulrike Ehlert and Roland von Känel: Psychoendocrinology and Psychoimmunology , Springer Berlin a. Heidelberg 2011.

Web links

Individual evidence

  1. ↑ cf. Dissertation on Obesity , FU Berlin , seen on April 12, 2013.
  2. ↑ cf. Bettina Lange, dissertation, Freiburg 2012, p. 8 ff (PDF; 3.3 MB).
  3. ↑ Hoch / Kreitz / Gaffling / Pischetsrieder / Hess in PlosOne, 8, e55354 of February 7, 2013 ( doi: 10.1371 / journal.pone.0055354 ) and the FAU web publication of April 16, 2013 and Scientific Reports, 5 , 10041 ( doi: 10.1038 / srep10041 ) with the FAU web publication of May 15, 2015 .
  4. ^ BR "Why Chips Are So Seductive"; DLF Nova "Chips - Until the bag is empty"; SPON "Food Formula - What Makes Chips and Chocolate Irresistible"; scinexx "Chips: What is the addiction trigger?".
  5. ↑ DLF Nova "Chips - Until the bag is empty".
  6. ↑ Der Tagesspiegel of April 12, 2013, p. 28.
  7. ^ [1] Der Standard , Essen ohne Hunger, April 11, 2013.
  8. ↑ Tobias Hoch, Silke Kreitz u. a .: Manganese-Enhanced Magnetic Resonance Imaging for Mapping of Whole Brain Activity Patterns Associated with the Intake of Snack Food in Ad Libitum Fed Rats. In: PLoS ONE. 8, 2013, p. E55354, doi: 10.1371 / journal.pone.0055354 .
  9. ↑ [2] The World , Science: Magical Attraction , viewed April 12, 2012