The Appetite Disorders
Hunger is an organic need to feed ourselves for recovering our energy and nutrient losses, representing an innate reflex. Appetite represents the desire to ingest a particular food, being a conditioned reflex, acquired trough previous experiences, especially gustative experiences. Nerve regulation of food ingestion is effectuated at the hypothalamus level where we can find the hunger center and satiety center connected by the functional connection with cortical centers of the limbic system and tonsillar system.
The need to feed ourselves is conditioned, on the one hand, by the somatic factor trough the value of food quantity and quality, and, on the other hand, by the nervous factor, trough the stimuli with the starting point from the stomach level (condition of gastric mucosa, hydrochloric acid secretion, parietal gastric and duodenal tonus). Psychological factor has an important role in regulating the appetite.
- Decrease of food ingestion or inappetence:
Represents the lack or the diminution of the desire to eat. It should be differentiated from the precocious satiety which occurs in the reducing the capacity of the stomach (gastric resections for complicated ulcers, sclera syphilitic stomach, gastric cancers of the scirrhus type, gastric hypotonia)
Is the absence of hunger or appetite, and can be classified as follows:
- Total – suppression of appetite for any food;
- Selective – suppression of the desire for a certain type of food (for fats in hepatic disorders and for meat, fats or bread in digestive neoplasms)
- Progressive – occurs frequently in gastric cancer
- Real – shows organic substrate
- False – has a functional substrate, often caused by the fear to ingest food because of pain (gastric and/or duodenal ulcer, odynophagia)
- Nervous – has a psychic substrate, consisting in refusal to eat
It represents the opposite of anorexia, namely increased appetite, and occurs in physiological conditions, such as during convalescence after diseases, in conditions of sustained physical exercise or in pathological conditions, such as in duodenal ulcer, intestinal parasitism, diabetes mellitus, hyperthyroidism.
4. Polyphagia or hyperphagia:
Represents the need of ingestion of large amounts of food to achieve a feeling of satiety and is common in diabetes mellitus and neurological disorders involving the hypothalamus (infectious or traumatic).
Is an imperious sensation of ingesting large amounts of food, exceeding the need of the body, and appears in some mental disorders.
Represents the loss of satiety sensation, and the patient would be eating nonstop; is common in psychiatric diseases and neurological disorders (brain tumors, senile dementia, cerebral lues).
It represents the degradation of appetite, and can take several forms:
- Malacia (the hunger for acid foods)
- Pica (ingestion of non-food products like sand and chalk)
- Pagophagia (the hunger for ice)
- Geophagia (the hunger for soil
- Allotriophagia (the pleasure of eating disgusting substances, eg. excrements )
Dysgeusia is common in certain mental disorders, as at some children with mineral or vitamin deficits, or in intestinal parasitism.
8. Merycism or rumination
Merycism or rumination Is regurgitating foods from stomach back into the mouth, with re-chewing them; is described in schizophrenia, oligophrenia, at children is a quasi-physiological phenomenon, especially when the food is administered quickly.
9. Sitiophobia is the refusal of ingesting any kind food.; is common in mental disorders.