The body contains two types of fats: white fat and brown fat. White fat is responsible for storing excess thermal energy in case of need, while brown fat cells burn and turn into heat. Recently, scientists have discovered that the transcription factor IRF4 (interferon regulatory factor 4) plays a key role in the heat production, energy expenditure and low temperature tolerance of brown fat. "based on this study, we may be able to find new drug targets that directly interfere with the pathways mentioned above." The scientists working on the study said that they hope to eventually use this mechanism of action to effectively treat obesity and diabetes.