By Hara Estroff Marano, published on May 1, 2003 - last reviewed on April 23, 2009
Help is here for treatment-resistant depression. Vitamin B folate or folic acid—found in citrus fruits, legumes, leafy green vegetables—is now part of the psychiatrist's arsenal of antidepressants.
Folate enhances response to antidepressant drugs: In patients previously unresponsive to selective serotonin reuptake inhibitors, folic acid boosted the response rate by 40 percent, according to Jonathan Alpert, Ph.D., an associate professor of psychiatry at Harvard.
British researchers also found that supplementing the diet of the clinically depressed with 500 micrograms of folate enhances the rate of response to Prozac, especially among women.
Folate modulates levels of neurotransmitters and is crucial to the production of metabolic power broker S-Adenosyl-Methionine or SAM-e, which contributes to the synthesis of nerve-cell membranes and activates serotonin, norepinephrine and dopamine, all of which are neurotransmitters linked to depression.
For the one-third to one-half of patients who do not respond to an initial antidepressant, folate supplementation makes sense, according to Alpert. "Folate is safe in the doses at issue (less than one milligram), it's inexpensive and well tolerated."