Sex differences exist in the regulation of energy homeostasis. Current studies indicate for instance that female mammals, including humans, are better protected against metabolic diseases during reproductive age. This is particularly important with regard to obesity, whose prevalence has tripled since 1975. However, it is still not fully understood how hormones, released by sex-specific reproductive glands, signal to the brain to regulate energy metabolism in females versus males. Researchers at Helmholtz Munich pursued the question and discovered a new protein called Cited1 within hypothalamic neurons that is involved in the regulation and sensitivity of satiety pathways.