Age-related anorexia counteracts the adequate supply in old age, in addition to the age-related decline of many bodily functions. Due to a dysregulation of the hunger and satiety mechanisms, unintentional weight loss occurs, increasing the risk of malnutrition and mortality. Research into the causes has various approaches, and a multifactorial relationship is being discussed. This work provides an overview of the current state of knowledge and describes approaches to dietary therapies. Supervision of the thesis by Prof. Dr. Silya Ottens.