Reif studied human medicine at the Julius Maximilian University of Würzburg and received his doctorate there at the Institute of Pharmacology.
He then completed his specialist training as a psychiatrist in the clinic for psychiatry, psychosomatics and psychotherapy there, first under H. Beckmann and then under J. Deckert.
He started his scientific career in Klaus-Peter Lesch's working group for molecular psychiatry, where he mainly dealt with the genetics of mental illnesses.
Since August 2014, Reif has been director of the Clinic for Psychiatry, Psychosomatics and Psychotherapy at the Johann Wolfgang Goethe University in Frankfurt am Main.
His scientific focus is on the field of translational psychiatry: with his work he tries to understand mental illnesses from the molecule through the neural system to the disease itself.