Evidence for...Vitamin B for depression

High vitamin B12 level and good treatment outcome may be associated in major depressive disorder.
Hintikka J et al.
BMC Psychiatry. 2003;3:17.
Higher vitamin B12 levels were significantly associated with a better outcome in 115 patients with major depressive disorder after 6 months' treatment.


The relationship between serum folate, vitamin B12, and homocysteine levels in major depressive disorder and the timing of improvement with fluoxetine.
Papakostas GI et al.
Int J Neuropsychopharmacol. 2005;8:523-8.
In 110 patients with major depressive disorder who responded to an 8-week trial of fluoxetine, low serum folate levels (≤2.5 ng/mL) were associated with a delayed onset of clinical improvement during treatment by, on average, 1.5 weeks. Onset of clinical improvement was defined as a 30% decrease in Hamilton Depression Scale scores that led to a 50% decrease by week 8.


Treatment of depression: time to consider folic acid and vitamin B12.
Coppen A and Bolander-Gouaille C.
J Psychopharmacol. 2005;19:59-65.
This review states that current clinical data show a strong association in major depression of a low plasma and particularly red cell folate, but also of low vitamin B12 status, and the authors suggest that oral doses of both folic acid (800 microg daily) and vitamin B12 (1 mg daily) should be tried to improve treatment outcome in depression.