A randomized, controlled study by the Department of Pharmacology of Government Medical College in Bhavnagar, Gujarat, India found that in a study of 60 patients with Major Depressive Disorder, curcumin (turmeric) was as effective as fluoxetine (Prozac) in improving scores on the Hamilton Depression Rating Scale, but without side effects.
Sanmukhani J, Satodia V, Trivedi J, Patel T, Tiwari D, Panchal B, Goel A, Tripathi CB. Efficacy and Safety of Curcumin in Major Depressive Disorder: A Randomized Controlled Trial. Phytotherapy Research. Online July 6, 2013
Of further interest:
Study Finds Turmeric Is As Effective As Prozac For Treating Depression (Collective Evolution)