INS and X-linked cone dysfunction syndrome with myopia: • Recruited through professional referrals and radio, newspaper and web-based (social media) advertisements• DSM-5 diagnosis BN or BED; no current treatment for ED or behavioral weight loss; at least 18 years; not requiring immediate treatment for medical complications because of the ED; no severe psychopathology; unstable on psychiatric medications for at least 1 month; no diabetes; no medication known to impact insulin or glucose levels; no history of bariatric surgery; no current pregnancy or lactating; no BMI <17.5 or >40