Hunger

The unpleasant visceral sensation arising from prolonged absence or insufficiency of nutrient intake, primarily mediated by hypothalamic centers and peripheral signals (ghrelin), and expressed clinically as a drive or motivation to seek and ingest food. Possible causes for polyphagia (excessive hunger) are diabetes, hypoglycemia triggering the release of ghrelin, hyperthyroidism, sleep deprivation, dehydration, stress, depression, Prader-Willi Syndrome, medications (steroids, antidepressants, antipsychotics, cannabis), and diets high in refined carbohydrates or lacking sufficient protein and healthy fats.