Hunger and eating and thirst are controlled by both the psychological and physiological factors. Sometimes a psychological factor may affect the physiological factor and vice versa and that affects the processes within our bodies that control this activities. When the glucose or the insulin levels are low in our bodies, these low levels are not sufficient and therefore the receptors that triggers hunger send signals to the brain and that creates the urge to eat so that the body can access the nutrients it requires (Pashley, 2013). The psychological issues such as stress, anxiety and nervousness s may also affect our physiological processes by either slowing digestion or fastening and that is why some people loose appetite, eat less when depressed because their brain controls their appetite and their ability to feel hunger. The psychological factors may also affect the dehydration processes and that explains why a person may mostly feel thirsty when nervous.
Anorexia nervosa is an eating disorder that affects people who feel that they are overweight even when it is clear that they are underweight. They eat very little and engage in extreme exercise to ensure they do not add weight at all (Kaye, Bailer & Klabunde, 2014). Their self-esteem is highly controlled by how people perceive their bodies. Female teenagers are the ones who suffer mostly from this disorder because they feel they have to possess a certain body side to look attractive. This type of people may feel tired all the time, have dry or yellowish skin, experience lanugo but unfortunately they will ignore all this signals the body is sending to them and maintain their eating disorder to lose weight.
Kaye, W. H., Bailer, U. F., & Klabunde, M. (2014). IS ANOREXIA NERVOSA AN EATING DISORDER? How neurobiology can help us understand the puzzling eating symptoms of anorexia nervosa.
Pashley, G. (2013). Professional conceptions of. Themes and Perspectives in Nursing, 138.