DOI 10.1007/s00702-005-0315-3 J Neural Transm (2005) 112: 979–985 Homocysteine plasma levels are elevated in females with anorexia nervosa Rapid Communication H. Frieling 1 , K. Ro ¨mer 1; , B. Ro ¨schke 1 , D. Bo ¨nsch 1 , J. Wilhelm 1 , R. Fiszer 1 , M. de Zwaan 2 , G. E. Jacoby 3 , J. Kornhuber 1 , and S. Bleich 1 1 Department of Psychiatry and Psychotherapy, and 2 Department of Psychosomatic Medicine and Psychotherapy, University Erlangen-Nuremberg, and 3 Klinik am Korso, Hospital for Eating Disorders, Bad Oeynhausen, Germany Received February 18, 2005; accepted March 30, 2005 Summary. In the present pilot study significantly (T ¼ 2.46, P ¼ 0.018) higher levels of homocysteine were found in female anorectic patients (14.07, SD 7.3 mmol=l; n ¼ 18) when compared with bulimic patients (10.25, SD 2.82; n ¼ 27) or healthy controls (8.10, SD 1.79; n ¼ 25). Since homocysteine can induce neuronal cell death leading to brain atrophy in different diseases and since it has been linked to depressive disorders these findings may have impor- tant implications for understanding common symptoms in patients suffering from anorexia. Keywords: Homocysteine, eating disorders, anorexia nervosa, bulimia nervosa. Introduction There is growing evidence that different psychiatric disorders such as alcohol- ism, depression, or possibly Alzheimer’s disease (AD) are associated with ele- vated plasma homocysteine levels (Bjelland et al., 2003; Bleich et al., 2000a, b, 2005; Bottiglieri et al., 2000; Clarke et al., 1998; Seshadri et al., 2002). Homo- cysteine acts as an agonist at the NMDA receptor, mediates excitotoxicity, and may disturb glutamatergic neurotransmission leading to impaired signal-to- noise ratio (Bleich et al., 2003b; Christie et al., 2005).  Present address: Department of Psychiatry and Psychotherapy, University of Basel, Switzerland