In patients with restrictive eating disorders there are alterations of hormones and other factors that affect the secretion of gonadotropin-releasing hormone (GnRH), including low levels of leptin and high levels of both ghrelin and peptide YY. β-endorphin, corticotropin-releasing hormone (CRH), dopamine, and γ-aminobutyric acid (GABA) are factor that negatively influence GnRH secretion. Some of these factors may also serve as hunger signals from the peripheral to the central nervous system and as links between nutrition and reproduction. Hallmark findings in adolescents and young adults with restrictive eating disorders include over-activity of the hypothalamic-pituitary-adrenal axis, suppression of the hypothalamic-pituitary-gonadal axis, and alterations of thyroid hormone regulation. FSH denotes follicle-stimulating hormone, LH lutenizing hormone, TSH thyrotropin, and T3 triiodothyronine.
Adapted from Gordon CM. Functional hypothalamic amenorrhea. N Engl J Med 2010; 363: 365-71. Copyright © 2010 Massachusetts Medical Society. Reprinted with permission.