Obesity is caused by overeating, consuming unhealthy food, and satisfying cravings. We propose that while overeating is strongly linked to emotions and consuming unhealthy food relates to poor education, cravings are a medical condition responsible for the majority of unnecessary calories. Cravings differ from hunger in that hunger can be postponed, whereas cravings require immediate satisfaction for a specific substance such as sugar or fat (e.g. cakes, burgers, ice cream). Research proves that cravings are caused by the imbalance of gut flora, blood glucose levels, brain chemicals (mainly neurotransmitters), and five specific hormones (ghrelin, dopamine, epinephrine, norepinephrine, and serotonin).