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Anorexia nervosa (anorexia) is an eating disorder characterised by voluntary starvation and exercise stress. Anorexia nervosa is a complex disease, involving psychological, sociological and physiological components. A person who is suffering from anorexia is known as an anorectic (although the spellings anorexic and anoretic also exist).
Anorexia also refers to loss of appetite, usually considered as a medical symptom.The cause(s) of anorexia is a matter of debate in medical circles and society in general. General perspectives fit between the poles of it being physiological or psychological (with the potential for sociological and cultural influences being a cause to various degrees) in origin.. Many now take the opinion that it is a mix of both, in that it is a psychological condition which is often (though not inherently) borne of certain conducive neurophysiologic conditions.
The primary physiological characteristics of anorexia nervosa are voluntary starvation and exercise stress. In addition to intentional starvation, subjects will also take part in a high level of physical activity. Anorexia nervosa also negatively impacts the immune system and the central nervous system (CNS).
It is also thought to be linked to serotonin and dopamine abnormalities.
Many individuals who have obsessive-compulsive disorders also have an eating-disordered parent, presumably connected with shared genetic characteristics.
Anorexic subjects will often go through a cycle of recovery and relapse.
There is increasing speculation that the onset of anorexia has a genetic component, with a certain gene linked to abnormalities with the neurotransmitterA neurotransmitter is a type of molecule that carries signals between neurons (nerve cells) at synapses in the nervous system. Neurotransmitters may be either excitatory ( EPSPs) or inhibitory ( IPSPs). That is, they may foster the initiation of a nerve i chemicalA chemical is any substance used in or obtained by a process in chemistry: A chemical compound is a substance consisting of two or more chemical elements that are chemically combined in fixed proportions. A chemical element is a substance that cannot be d serotonin being shown to be more common amongst sufferers than the general population. Such genetic characteristics might potentially equate to an easier path towards overly high serotonin levels, thus instilling heightened levels of anxiety and the like. Biologically, when a person is in a state of starvation, their levels of serotonin decrease, and thence increase again upon the consumption of food because of the tryptophanTryptophan is an amino acid and essential in human nutrition. It is one of the 20 amino acids in the genetic code ( codon UGG , and its symbol is Trp or W''. Molecular formula: C H N O Molecular weight: 204. 23 Isoelectric point: pH 5. 89 CAS number: 73-2 amino acidIn chemistry, an amino acid is any molecule that contains both amino and carboxylic acid functional groups. In biochemistry, this shorter and more general term is frequently used to refer to alpha amino acids: those amino acids in which the amino and carbs contained therein (typtophan is used by the body to synthesise serotonin). This raises the spectre that the anorectic is conditionedThis article is about the psychological term. Conditioning is also an engineering term for putting something (for example, a communications link) into a particular condition. Conditioning is a psychological term for what Ivan Pavlov described as the learn into avoiding food to reduce their anxiety, and that there may be yet another layer of complexity with respects to the cause/effect relationship between physiological factors and the mental beliefs of the anorectic.