Hypothalamic Hyperphagia Injury to hypothalamus causing obesity due to overeating. Cancer Anorexia Anorexia due to a cancer growth.
Patient reduces food intake.
This leads to weight loss. Conversely, in underdeveloped countries, upper class tend toward obesity and poor are thin. Possible reasoning in evolition. Those who survived famine in prehistory now living in a calorie-rich world tend toward obesity. All physiological anolamies studied in AN cases appear to be results of AN behaviour rather than causes.