Final answer:
Possible causes for a patient with anorexia nervosa who exercises excessively include malnutrition, excessive exercise, genetic factors, and psychological issues. Anorexia nervosa leads to severely low body weight and can have life-threatening health consequences.
Step-by-step explanation:
If a patient has anorexia nervosa and works out constantly, the possible causes of their condition could include malnutrition, excessive exercise, genetic factors, and psychological issues. Anorexia nervosa is an eating disorder where individuals maintain a very low body weight due to excessive food restriction and/or exercise. They may have a distorted body image and see themselves as overweight even if they are underweight. This condition can lead to serious health issues, including bone loss, heart failure, and, in extreme cases, death. Environmental factors such as cultural pressures and past traumas can also play a role in the development of eating disorders.